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  • Why keylistener is not working here?

    - by swift
    i have implemented keylistener interface and implemented all the needed methods but when i press the key nothing happens here, why? package swing; import java.awt.Color; import java.awt.Dimension; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.GridLayout; import java.awt.Point; import java.awt.RenderingHints; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.awt.event.MouseMotionListener; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.awt.image.BufferedImage; import javax.swing.BorderFactory; import javax.swing.BoxLayout; import javax.swing.ImageIcon; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLayeredPane; import javax.swing.JPanel; import javax.swing.JTextArea; class Paper extends JPanel implements MouseListener,MouseMotionListener,ActionListener,KeyListener { static BufferedImage image; String shape; Color color=Color.black; Point start; Point end; Point mp; Button elipse=new Button("elipse"); int x[]=new int[50]; int y[]=new int[50]; Button rectangle=new Button("rect"); Button line=new Button("line"); Button roundrect=new Button("roundrect"); Button polygon=new Button("poly"); Button text=new Button("text"); ImageIcon erasericon=new ImageIcon("images/eraser.gif"); JButton erase=new JButton(erasericon); JButton[] colourbutton=new JButton[9]; String selected; Point label; String key; int ex,ey;//eraser //DatagramSocket dataSocket; JButton button = new JButton("test"); JLayeredPane layerpane; Point p=new Point(); int w,h; public Paper() { JFrame frame=new JFrame("Whiteboard"); frame.setVisible(true); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setSize(640, 480); frame.setBackground(Color.black); layerpane=frame.getLayeredPane(); setWidth(539,444); setBounds(69,0,555,444); layerpane.add(this,new Integer(2)); layerpane.add(this.addButtons(),new Integer(0)); setLayout(null); setOpaque(false); addMouseListener(this); addMouseMotionListener(this); setFocusable(true); addKeyListener(this); System.out.println(isFocusable()); setBorder(BorderFactory.createLineBorder(Color.black)); } public void paintComponent(Graphics g) { try { super.paintComponent(g); g.drawImage(image, 0, 0, this); Graphics2D g2 = (Graphics2D)g; if(color!=null) g2.setPaint(color); if(start!=null && end!=null) { if(selected==("elipse")) g2.drawOval(start.x, start.y,(end.x-start.x),(end.y-start.y)); else if(selected==("rect")) g2.drawRect(start.x, start.y, (end.x-start.x),(end.y-start.y)); else if(selected==("rrect")) g2.drawRoundRect(start.x, start.y, (end.x-start.x),(end.y-start.y),11,11); else if(selected==("line")) g2.drawLine(start.x,start.y,end.x,end.y); else if(selected==("poly")) g2.drawPolygon(x,y,2); } } catch(Exception e) {} } //Function to draw the shape on image public void draw() { Graphics2D g2 = image.createGraphics(); g2.setPaint(color); if(start!=null && end!=null) { if(selected=="line") g2.drawLine(start.x, start.y, end.x, end.y); else if(selected=="elipse") g2.drawOval(start.x, start.y, (end.x-start.x),(end.y-start.y)); else if(selected=="rect") g2.drawRect(start.x, start.y, (end.x-start.x),(end.y-start.y)); else if(selected==("rrect")) g2.drawRoundRect(start.x, start.y, (end.x-start.x),(end.y-start.y),11,11); else if(selected==("poly")) g2.drawPolygon(x,y,2); } if(label!=null) { JTextArea textarea=new JTextArea(); if(selected==("text")) { textarea.setBounds(label.x, label.y, 50, 50); textarea.setMaximumSize(new Dimension(100,100)); textarea.setBackground(new Color(237,237,237)); add(textarea); g2.drawString("key",label.x,label.y); } } start=null; repaint(); g2.dispose(); } public void text() { System.out.println(label); } //Function which provides the erase functionality public void erase() { Graphics2D pic=(Graphics2D) image.getGraphics(); Color erasecolor=new Color(237,237,237); pic.setPaint(erasecolor); if(start!=null) pic.fillRect(start.x, start.y, 10, 10); } //To set the size of the image public void setWidth(int x,int y) { System.out.println("("+x+","+y+")"); w=x; h=y; image = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB); } //Function to add buttons into the panel, calling this function returns a panel public JPanel addButtons() { JPanel buttonpanel=new JPanel(); buttonpanel.setMaximumSize(new Dimension(70,70)); JPanel shape=new JPanel(); JPanel colourbox=new JPanel(); shape.setLayout(new GridLayout(4,2)); shape.setMaximumSize(new Dimension(70,140)); colourbox.setLayout(new GridLayout(3,3)); colourbox.setMaximumSize(new Dimension(70,70)); buttonpanel.setLayout(new BoxLayout(buttonpanel,BoxLayout.Y_AXIS)); elipse.addActionListener(this); elipse.setToolTipText("Elipse"); rectangle.addActionListener(this); rectangle.setToolTipText("Rectangle"); line.addActionListener( this); line.setToolTipText("Line"); erase.addActionListener(this); erase.setToolTipText("Eraser"); roundrect.addActionListener(this); roundrect.setToolTipText("Round rect"); polygon.addActionListener(this); polygon.setToolTipText("Polygon"); text.addActionListener(this); text.setToolTipText("Text"); shape.add(elipse); shape.add(rectangle); shape.add(line); shape.add(erase); shape.add(roundrect); shape.add(polygon); shape.add(text); buttonpanel.add(shape); for(int i=0;i<9;i++) { colourbutton[i]=new JButton(); colourbox.add(colourbutton[i]); if(i==0) colourbutton[0].setBackground(Color.black); else if(i==1) colourbutton[1].setBackground(Color.white); else if(i==2) colourbutton[2].setBackground(Color.red); else if(i==3) colourbutton[3].setBackground(Color.orange); else if(i==4) colourbutton[4].setBackground(Color.blue); else if(i==5) colourbutton[5].setBackground(Color.green); else if(i==6) colourbutton[6].setBackground(Color.pink); else if(i==7) colourbutton[7].setBackground(Color.magenta); else if(i==8) colourbutton[8].setBackground(Color.cyan); colourbutton[i].addActionListener(this); } buttonpanel.add(colourbox); buttonpanel.setBounds(0, 0, 70, 210); return buttonpanel; } public void mouseClicked(MouseEvent e) { if(selected=="text") { label=new Point(); label=e.getPoint(); draw(); } } @Override public void mouseEntered(MouseEvent arg0) { } public void mouseExited(MouseEvent arg0) { } public void mousePressed(MouseEvent e) { if(selected=="line"||selected=="erase"||selected=="text") { start=e.getPoint(); } else if(selected=="elipse"||selected=="rect"||selected=="rrect") { mp = e.getPoint(); } else if(selected=="poly") { x[0]=e.getX(); y[0]=e.getY(); } } public void mouseReleased(MouseEvent e) { if(start!=null) { if(selected=="line") { end=e.getPoint(); } else if(selected=="elipse"||selected=="rect"||selected=="rrect") { end.x = Math.max(mp.x,e.getX()); end.y = Math.max(mp.y,e.getY()); } else if(selected=="poly") { x[1]=e.getX(); y[1]=e.getY(); } draw(); } } public void mouseDragged(MouseEvent e) { if(end==null) end = new Point(); if(start==null) start = new Point(); if(selected=="line") { end=e.getPoint(); } else if(selected=="erase") { start=e.getPoint(); erase(); } else if(selected=="elipse"||selected=="rect"||selected=="rrect") { start.x = Math.min(mp.x,e.getX()); start.y = Math.min(mp.y,e.getY()); end.x = Math.max(mp.x,e.getX()); end.y = Math.max(mp.y,e.getY()); } else if(selected=="poly") { x[1]=e.getX(); y[1]=e.getY(); } repaint(); } public void mouseMoved(MouseEvent arg0) {} public void actionPerformed(ActionEvent e) { if(e.getSource()==elipse) selected="elipse"; else if(e.getSource()==line) selected="line"; else if(e.getSource()==rectangle) selected="rect"; else if(e.getSource()==erase) { selected="erase"; System.out.println(selected); erase(); } else if(e.getSource()==roundrect) selected="rrect"; else if(e.getSource()==polygon) selected="poly"; else if(e.getSource()==text) selected="text"; if(e.getSource()==colourbutton[0]) color=Color.black; else if(e.getSource()==colourbutton[1]) color=Color.white; else if(e.getSource()==colourbutton[2]) color=Color.red; else if(e.getSource()==colourbutton[3]) color=Color.orange; else if(e.getSource()==colourbutton[4]) color=Color.blue; else if(e.getSource()==colourbutton[5]) color=Color.green; else if(e.getSource()==colourbutton[6]) color=Color.pink; else if(e.getSource()==colourbutton[7]) color=Color.magenta; else if(e.getSource()==colourbutton[8]) color=Color.cyan; } @Override public void keyPressed(KeyEvent e) { System.out.println("pressed"); } @Override public void keyReleased(KeyEvent e) { System.out.println("key released"); } @Override public void keyTyped(KeyEvent e) { System.out.println("Typed"); } public static void main(String[] a) { new Paper(); } } class Button extends JButton { String name; public Button(String name) { this.name=name; } public void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2 = (Graphics2D)g; g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); //g2.setStroke(new BasicStroke(1.2f)); if (name == "line") g.drawLine(5,5,30,30); if (name == "elipse") g.drawOval(5,7,25,20); if (name== "rect") g.drawRect(5,5,25,23); if (name== "roundrect") g.drawRoundRect(5,5,25,23,10,10); int a[]=new int[]{20,9,20,23,20}; int b[]=new int[]{9,23,25,20,9}; if (name== "poly") g.drawPolyline(a, b, 5); if (name== "text") g.drawString("Text",5, 22); } }

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  • Program crash on deque from queue

    - by SwedishGit
    My first question asked here, so please excuse if I fail to include something... I'm working on a homework project, which basically consists of creating a "Jukebox" (importing/exporting albums from txt files, creating and "playing" a playlist, etc.). I've become stuck on one point: When "playing" the playlist, which consists of a self-made Queue, a copy of it is made from which songs are dequeued and printed out with a time delay. This appears to run fine on the first run through the program, but if the "play" option is chosen again (with the same playlist, created from a different menu option), it crashes before managing to print the first song. It also crashes if creating a new playlist, but then it manages to print some songs (seem to depend on the number of songs in the first/new playlists...) before crashing. With printouts I've been able to track the crashing down to being on the "item = n-data" call in the deque function... but can't get my head around why this would crash. Below is the code I think should be relevant... let me know if there are other parts that would help if I include. Edit: The Debug Error shown on crash is: R6010 abort() has been called The method to play from the playlist: void Jukebox::playList() { if(songList.getNodes() > 0) { Queue tmpList(songList); Song tmpSong; while(tmpList.deque(tmpSong)) { clock_t temp; temp = clock () + 2 * CLOCKS_PER_SEC ; while (clock() < temp) {} } } else cout << "There are no songs in the playlist!" << endl; } Queue: // Queue.h - Projekt-uppgift // Håkan Sjölin 2014-05-31 //----------------------------------------------------------------------------- #ifndef queue_h #define queue_h #include "Song.h" using namespace std; typedef Song Item; class Node; class Queue { private: Node *first; Node *last; int nodes; public: Queue():first(nullptr),last(nullptr),nodes(0){}; ~Queue(); void enque(Item item); bool deque(Item &item); int getNodes() const { return nodes; } void empty(); }; #endif // Queue.cpp - Projekt-uppgift // Håkan Sjölin 2014-05-31 //----------------------------------------------------------------------------- #include "queue.h" using namespace std; class Node { public: Node *next; Item data; Node (Node *n, Item newData) : next(n), data(newData) {} }; //------------------------------------------------------------------------------ // Funktionsdefinitioner för klassen Queue //------------------------------------------------------------------------------ //------------------------------------------------------------------------------ // Destruktor //------------------------------------------------------------------------------ Queue::~Queue() { while(first!=0) { Node *tmp = first; first = first->next; delete tmp; } } //------------------------------------------------------------------------------ // Lägg till data sist i kön //------------------------------------------------------------------------------ void Queue::enque(Item item) { Node *pNew = new Node(0,item); if(getNodes() < 1) first = pNew; else last->next = pNew; last = pNew; nodes++; } //------------------------------------------------------------------------------ // Ta bort data först i kön //------------------------------------------------------------------------------ bool Queue::deque(Item &item) { if(getNodes() < 1) return false; //cout << "deque: test2" << endl; Node *n = first; //cout << "deque: test3" << endl; //cout << "item = " << item << endl; //cout << "first = " << first << endl; //cout << "n->data = " << n->data << endl; item = n->data; //cout << "deque: test4" << endl; first = first->next; //delete n; nodes--; if(getNodes() < 1) // Kön BLEV tom last = nullptr; return true; } //------------------------------------------------------------------------------ // Töm kön //------------------------------------------------------------------------------ void Queue::empty() { while (getNodes() > 0) { Item item; deque(item); } } //------------------------------------------------------------------------------ Song: // Song.h - Projekt-uppgift // Håkan Sjölin 2014-05-15 //----------------------------------------------------------------------------- #ifndef song_h #define song_h #include "Time.h" #include <string> #include <iostream> using namespace std; class Song { private: string title; string artist; Time length; public: Song(); Song(string pTitle, string pArtist, Time pLength); // Setfunktioner void setTitle(string pTitle); void setArtist(string pArtist); void setLength(Time pLength); // Getfunktioner string getTitle() const { return title;} string getArtist() const { return artist;} Time getLength() const { return length;} }; ostream &operator<<(ostream &os, const Song &song); istream &operator>>(istream &is, Song &song); #endif // Song.cpp - Projekt-uppgift // Håkan Sjölin 2014-05-15 //----------------------------------------------------------------------------- #include "Song.h" #include "Constants.h" #include <iostream> //------------------------------------------------------------------------------ // Definiering av Songs medlemsfunktioner //------------------------------------------------------------------------------ // Fövald konstruktor //------------------------------------------------------------------------------ Song::Song() { } //------------------------------------------------------------------------------ // Initieringskonstruktor //------------------------------------------------------------------------------ Song::Song(string pTitle, string pArtist, Time pLength) { title = pTitle; artist = pArtist; length = pLength; } //------------------------------------------------------------------------------ // Setfunktioner //------------------------------------------------------------------------------ //------------------------------------------------------------------------------ // setTitle // Ange titel //------------------------------------------------------------------------------ void Song::setTitle(string pTitle) { title = pTitle; } //------------------------------------------------------------------------------ // setArtist // Ange artist //------------------------------------------------------------------------------ void Song::setArtist(string pArtist) { artist = pArtist; } //------------------------------------------------------------------------------ // setTitle // Ange titel //------------------------------------------------------------------------------ void Song::setLength(Time pLength) { length = pLength; } //--------------------------------------------------------------------------- // Överlagring av utskriftsoperatorn //--------------------------------------------------------------------------- ostream &operator<<(ostream &os, const Song &song) { os << song.getTitle() << DELIM << song.getArtist() << DELIM << song.getLength(); return os; } //--------------------------------------------------------------------------- // Överlagring av inmatningsoperatorn //--------------------------------------------------------------------------- istream &operator>>(istream &is, Song &song) { string tmpString; Time tmpLength; getline(is, tmpString, DELIM); song.setTitle(tmpString); getline(is, tmpString, DELIM); song.setArtist(tmpString); is >> tmpLength; is.get(); song.setLength(tmpLength); return is; } //--------------------------------------------------------------------------- Album: // Album.h - Projekt-uppgift // Håkan Sjölin 2014-05-17 //----------------------------------------------------------------------------- #ifndef album_h #define album_h #include "Song.h" #include <string> #include <vector> #include <iostream> using namespace std; class Album { private: string name; vector<Song> songs; public: Album(); Album(string pNameTitle, vector<Song> pSongs); // Setfunktioner void setName(string pName); // Getfunktioner string getName() const { return name;} vector<Song> getSongs() const { return songs;} int getNumberOfSongs() const { return songs.size();} Time getTotalTime() const; void addSong(Song pSong); bool operator<(const Album &album) const; }; ostream &operator<<(ostream &os, const Album &album); istream &operator>>(istream &is, Album &album); #endif // Album.cpp - Projekt-uppgift // Håkan Sjölin 2014-05-17 //----------------------------------------------------------------------------- #include "Album.h" #include "Constants.h" #include <iostream> #include <string> //------------------------------------------------------------------------------ // Definiering av Albums medlemsfunktioner //------------------------------------------------------------------------------ // Fövald konstruktor //------------------------------------------------------------------------------ Album::Album() { } //------------------------------------------------------------------------------ // Initieringskonstruktor //------------------------------------------------------------------------------ Album::Album(string pName, vector<Song> pSongs) { name = pName; songs = pSongs; } //------------------------------------------------------------------------------ // Setfunktioner //------------------------------------------------------------------------------ //------------------------------------------------------------------------------ // setName // Ange namn //------------------------------------------------------------------------------ void Album::setName(string pName) { name = pName; } //------------------------------------------------------------------------------ // addSong // Lägg till song //------------------------------------------------------------------------------ void Album::addSong(Song pSong) { songs.push_back(pSong); } //------------------------------------------------------------------------------ // getTotalTime // Returnera total speltid //------------------------------------------------------------------------------ Time Album::getTotalTime() const { Time tTime(0,0,0); for(Song s : songs) { tTime = tTime + s.getLength(); } return tTime; } //--------------------------------------------------------------------------- // Mindre än //--------------------------------------------------------------------------- bool Album::operator<(const Album &album) const { return getTotalTime() < album.getTotalTime(); } //--------------------------------------------------------------------------- // Överlagring av utskriftsoperatorn //--------------------------------------------------------------------------- ostream &operator<<(ostream &os, const Album &album) { os << album.getName() << endl; os << album.getNumberOfSongs() << endl; for (size_t i = 0; i < album.getSongs().size(); i++) os << album.getSongs().at(i) << endl; return os; } //--------------------------------------------------------------------------- // Överlagring av inmatningsoperatorn //--------------------------------------------------------------------------- istream &operator>>(istream &is, Album &album) { string tmpString; int tmpNumberOfSongs; Song tmpSong; getline(is, tmpString); album.setName(tmpString); is >> tmpNumberOfSongs; is.get(); for (int i = 0; i < tmpNumberOfSongs; i++) { is >> tmpSong; album.addSong(tmpSong); } return is; } //--------------------------------------------------------------------------- Time: // Time.h - Projekt-uppgift // Håkan Sjölin 2014-05-15 //----------------------------------------------------------------------------- #ifndef time_h #define time_h #include <iostream> using namespace std; class Time { private: int hours; int minutes; int seconds; public: Time(); Time(int pHour, int pMinute, int pSecond); // Setfunktioner void setHour(int pHour); void setMinute(int pMinute); void setSecond(int pSecond); // Getfunktioner int getHour() const { return hours;} int getMinute() const { return minutes;} int getSecond() const { return seconds;} Time operator+(const Time &time) const; bool operator==(const Time &time) const; bool operator<(const Time &time) const; }; ostream &operator<<(ostream &os, const Time &time); istream &operator>>(istream &is, Time &Time); #endif // Time.cpp - Projekt-uppgift // Håkan Sjölin 2014-05-15 //----------------------------------------------------------------------------- #include "Time.h" #include <iostream> //------------------------------------------------------------------------------ // Definiering av Times medlemsfunktioner //------------------------------------------------------------------------------ // Fövald konstruktor //------------------------------------------------------------------------------ Time::Time() { } //------------------------------------------------------------------------------ // Initieringskonstruktor //------------------------------------------------------------------------------ Time::Time(int pHour, int pMinute, int pSecond) { setHour(pHour); setMinute(pMinute); setSecond(pSecond); } //------------------------------------------------------------------------------ // Setfunktioner //------------------------------------------------------------------------------ //------------------------------------------------------------------------------ // setHour // Ange timme //------------------------------------------------------------------------------ void Time::setHour(int pHour) { if(pHour>-1) hours = pHour; else hours = 0; } //------------------------------------------------------------------------------ // setMinute // Ange minut //------------------------------------------------------------------------------ void Time::setMinute(int pMinute) { if(pMinute < 60 && pMinute > -1) { minutes = pMinute; } else minutes = 0; } //------------------------------------------------------------------------------ // setSecond // Ange sekund //------------------------------------------------------------------------------ void Time::setSecond(int pSecond) { if(pSecond < 60 && pSecond > -1) { seconds = pSecond; } else seconds = 0; } //--------------------------------------------------------------------------- // Överlagring av utskriftsoperatorn //--------------------------------------------------------------------------- ostream &operator<<(ostream &os, const Time &time) { os << time.getHour()*3600+time.getMinute()*60+time.getSecond(); return os; } //--------------------------------------------------------------------------- // Överlagring av inmatningsoperatorn //--------------------------------------------------------------------------- istream &operator>>(istream &is, Time &time) { int tmp; is >> tmp; time.setSecond(tmp%60); time.setMinute((tmp/60)%60); time.setHour(tmp/3600); return is; } //--------------------------------------------------------------------------- // Likhet //-------------------------------------------------------------------------- bool Time::operator==(const Time &time) const { return hours == time.getHour() && minutes == time.getMinute() && seconds == time.getSecond(); } //--------------------------------------------------------------------------- // Mindre än //--------------------------------------------------------------------------- bool Time::operator<(const Time &time) const { if(hours == time.getHour()) { if(minutes == time.getMinute()) { return seconds < time.getSecond(); } else { return minutes < time.getMinute(); } } else { return hours < time.getHour(); } } //--------------------------------------------------------------------------- // Addition //--------------------------------------------------------------------------- Time Time::operator+(const Time &time) const { return Time(hours+time.getHour() + (minutes+time.getMinute() + (seconds+time.getSecond())/60)/60, (minutes+time.getMinute() + (seconds+time.getSecond())/60)%60, (seconds+time.getSecond())%60); } //--------------------------------------------------------------------------- Thanks in advance for any help! Edit2: Didn't think of including the more detailed crash info (as it didn't show in the crash pop-up, so to say). Anyway, here it is: Output: 'Jukebox.exe' (Win32): Loaded 'C:\Users\Håkan\Documents\Studier - IT\Objektbaserad programmering i C++\Inlämningsuppgifter\Projekt\Jukebox\Debug\Jukebox.exe'. Symbols loaded. 'Jukebox.exe' (Win32): Loaded 'C:\Windows\SysWOW64\ntdll.dll'. Cannot find or open the PDB file. 'Jukebox.exe' (Win32): Loaded 'C:\Windows\SysWOW64\kernel32.dll'. Cannot find or open the PDB file. 'Jukebox.exe' (Win32): Loaded 'C:\Windows\SysWOW64\KernelBase.dll'. Cannot find or open the PDB file. 'Jukebox.exe' (Win32): Loaded 'C:\Windows\SysWOW64\msvcp110d.dll'. Symbols loaded. 'Jukebox.exe' (Win32): Loaded 'C:\Windows\SysWOW64\msvcr110d.dll'. Symbols loaded. The thread 0xe50 has exited with code 0 (0x0). Unhandled exception at 0x0083630C in Jukebox.exe: 0xC0000005: Access violation reading location 0x0000003C. Call stack: > Jukebox.exe!Song::getLength() Line 27 C++ Jukebox.exe!operator<<(std::basic_ostream<char,std::char_traits<char> > & os, const Song & song) Line 59 C++ Jukebox.exe!Queue::deque(Song & item) Line 55 C++ Jukebox.exe!Jukebox::playList() Line 493 C++ Jukebox.exe!Jukebox::play() Line 385 C++ Jukebox.exe!Jukebox::run() Line 536 C++ Jukebox.exe!main() Line 547 C++ Jukebox.exe!__tmainCRTStartup() Line 536 C Jukebox.exe!mainCRTStartup() Line 377 C kernel32.dll!754d86e3() Unknown [Frames below may be incorrect and/or missing, no symbols loaded for kernel32.dll] ntdll.dll!7748bf39() Unknown ntdll.dll!7748bf0c() Unknown

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  • NullPointerException when linking to Service that uses ContentProvider

    - by Danny Chia
    H.i everyone, this is my first post here! Anyways, I'm trying to write a "todo list" application. It stores the data in a ContentProvider, which is accessed via a Service. However, my app crashes at launch. My code is below: Manifest file: <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.examples.todolist" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name" android:debuggable="True"> <activity android:name=".ToDoList" android:label="@string/app_name" android:theme="@style/ToDoTheme"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <service android:name="TodoService"/> <provider android:name="TodoProvider" android:authorities="com.examples.provider.todolist" /> </application> <uses-sdk android:minSdkVersion="7" /> </manifest> ToDoList.java: package com.examples.todolist; import com.examples.todolist.TodoService.LocalBinder; import java.util.ArrayList; import java.util.Date; import android.app.Activity; import android.content.SharedPreferences; import android.database.Cursor; import android.os.AsyncTask; import android.os.Bundle; import android.view.ContextMenu; import android.content.ComponentName; import android.content.Context; import android.content.Intent; import android.content.ServiceConnection; import android.os.IBinder; import android.view.KeyEvent; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.View.OnKeyListener; import android.widget.AdapterView; import android.widget.EditText; import android.widget.ListView; import android.widget.Toast; public class ToDoList extends Activity { static final private int ADD_NEW_TODO = Menu.FIRST; static final private int REMOVE_TODO = Menu.FIRST + 1; private static final String TEXT_ENTRY_KEY = "TEXT_ENTRY_KEY"; private static final String ADDING_ITEM_KEY = "ADDING_ITEM_KEY"; private static final String SELECTED_INDEX_KEY = "SELECTED_INDEX_KEY"; private boolean addingNew = false; private ArrayList<ToDoItem> todoItems; private ListView myListView; private EditText myEditText; private ToDoItemAdapter aa; int entries = 0; int notifs = 0; //ToDoDBAdapter toDoDBAdapter; Cursor toDoListCursor; TodoService mService; boolean mBound = false; /** Called when the activity is first created. */ public void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(R.layout.main); myListView = (ListView)findViewById(R.id.myListView); myEditText = (EditText)findViewById(R.id.myEditText); todoItems = new ArrayList<ToDoItem>(); int resID = R.layout.todolist_item; aa = new ToDoItemAdapter(this, resID, todoItems); myListView.setAdapter(aa); myEditText.setOnKeyListener(new OnKeyListener() { public boolean onKey(View v, int keyCode, KeyEvent event) { if (event.getAction() == KeyEvent.ACTION_DOWN) if (keyCode == KeyEvent.KEYCODE_DPAD_CENTER) { ToDoItem newItem = new ToDoItem(myEditText.getText().toString(), 0); mService.insertTask(newItem); updateArray(); myEditText.setText(""); entries++; Toast.makeText(ToDoList.this, "Entry added", Toast.LENGTH_SHORT).show(); aa.notifyDataSetChanged(); cancelAdd(); return true; } return false; } }); registerForContextMenu(myListView); restoreUIState(); populateTodoList(); } private void populateTodoList() { // Get all the todo list items from the database. toDoListCursor = mService. getAllToDoItemsCursor(); startManagingCursor(toDoListCursor); // Update the array. updateArray(); Toast.makeText(this, "Todo list retrieved", Toast.LENGTH_SHORT).show(); } private void updateArray() { toDoListCursor.requery(); todoItems.clear(); if (toDoListCursor.moveToFirst()) do { String task = toDoListCursor.getString(toDoListCursor.getColumnIndex(ToDoDBAdapter.KEY_TASK)); long created = toDoListCursor.getLong(toDoListCursor.getColumnIndex(ToDoDBAdapter.KEY_CREATION_DATE)); int taskid = toDoListCursor.getInt(toDoListCursor.getColumnIndex(ToDoDBAdapter.KEY_ID)); ToDoItem newItem = new ToDoItem(task, new Date(created), taskid); todoItems.add(0, newItem); } while(toDoListCursor.moveToNext()); aa.notifyDataSetChanged(); } private void restoreUIState() { // Get the activity preferences object. SharedPreferences settings = getPreferences(0); // Read the UI state values, specifying default values. String text = settings.getString(TEXT_ENTRY_KEY, ""); Boolean adding = settings.getBoolean(ADDING_ITEM_KEY, false); // Restore the UI to the previous state. if (adding) { addNewItem(); myEditText.setText(text); } } @Override public void onSaveInstanceState(Bundle outState) { outState.putInt(SELECTED_INDEX_KEY, myListView.getSelectedItemPosition()); super.onSaveInstanceState(outState); } @Override public void onRestoreInstanceState(Bundle savedInstanceState) { int pos = -1; if (savedInstanceState != null) if (savedInstanceState.containsKey(SELECTED_INDEX_KEY)) pos = savedInstanceState.getInt(SELECTED_INDEX_KEY, -1); myListView.setSelection(pos); } @Override protected void onPause() { super.onPause(); // Get the activity preferences object. SharedPreferences uiState = getPreferences(0); // Get the preferences editor. SharedPreferences.Editor editor = uiState.edit(); // Add the UI state preference values. editor.putString(TEXT_ENTRY_KEY, myEditText.getText().toString()); editor.putBoolean(ADDING_ITEM_KEY, addingNew); // Commit the preferences. editor.commit(); } @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); // Create and add new menu items. MenuItem itemAdd = menu.add(0, ADD_NEW_TODO, Menu.NONE, R.string.add_new); MenuItem itemRem = menu.add(0, REMOVE_TODO, Menu.NONE, R.string.remove); // Assign icons itemAdd.setIcon(R.drawable.add_new_item); itemRem.setIcon(R.drawable.remove_item); // Allocate shortcuts to each of them. itemAdd.setShortcut('0', 'a'); itemRem.setShortcut('1', 'r'); return true; } @Override public boolean onPrepareOptionsMenu(Menu menu) { super.onPrepareOptionsMenu(menu); int idx = myListView.getSelectedItemPosition(); String removeTitle = getString(addingNew ? R.string.cancel : R.string.remove); MenuItem removeItem = menu.findItem(REMOVE_TODO); removeItem.setTitle(removeTitle); removeItem.setVisible(addingNew || idx > -1); return true; } @Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) { super.onCreateContextMenu(menu, v, menuInfo); menu.setHeaderTitle("Selected To Do Item"); menu.add(0, REMOVE_TODO, Menu.NONE, R.string.remove); } @Override public boolean onOptionsItemSelected(MenuItem item) { super.onOptionsItemSelected(item); int index = myListView.getSelectedItemPosition(); switch (item.getItemId()) { case (REMOVE_TODO): { if (addingNew) { cancelAdd(); } else { removeItem(index); } return true; } case (ADD_NEW_TODO): { addNewItem(); return true; } } return false; } @Override public boolean onContextItemSelected(MenuItem item) { super.onContextItemSelected(item); switch (item.getItemId()) { case (REMOVE_TODO): { AdapterView.AdapterContextMenuInfo menuInfo; menuInfo =(AdapterView.AdapterContextMenuInfo)item.getMenuInfo(); int index = menuInfo.position; removeItem(index); return true; } } return false; } @Override public void onDestroy() { super.onDestroy(); } private void cancelAdd() { addingNew = false; myEditText.setVisibility(View.GONE); } private void addNewItem() { addingNew = true; myEditText.setVisibility(View.VISIBLE); myEditText.requestFocus(); } private void removeItem(int _index) { // Items are added to the listview in reverse order, so invert the index. //toDoDBAdapter.removeTask(todoItems.size()-_index); ToDoItem item = todoItems.get(_index); final long selectedId = item.getTaskId(); mService.removeTask(selectedId); entries--; Toast.makeText(this, "Entry deleted", Toast.LENGTH_SHORT).show(); updateArray(); } @Override protected void onStart() { super.onStart(); Intent intent = new Intent(this, TodoService.class); bindService(intent, mConnection, Context.BIND_AUTO_CREATE); } @Override protected void onStop() { super.onStop(); // Unbind from the service if (mBound) { unbindService(mConnection); mBound = false; } } private ServiceConnection mConnection = new ServiceConnection() { public void onServiceConnected(ComponentName className, IBinder service) { LocalBinder binder = (LocalBinder) service; mService = binder.getService(); mBound = true; } public void onServiceDisconnected(ComponentName arg0) { mBound = false; } }; public class TimedToast extends AsyncTask<Long, Integer, Integer> { @Override protected Integer doInBackground(Long... arg0) { if (notifs < 15) { try { Toast.makeText(ToDoList.this, entries + " entries left", Toast.LENGTH_SHORT).show(); notifs++; Thread.sleep(20000); } catch (InterruptedException e) { } } return 0; } } } TodoService.java: package com.examples.todolist; import android.app.Service; import android.content.ContentResolver; import android.content.ContentValues; import android.content.Intent; import android.database.Cursor; import android.os.Binder; import android.os.IBinder; public class TodoService extends Service { private final IBinder mBinder = new LocalBinder(); @Override public IBinder onBind(Intent arg0) { return mBinder; } public class LocalBinder extends Binder { TodoService getService() { return TodoService.this; } } public void insertTask(ToDoItem _task) { ContentResolver cr = getContentResolver(); ContentValues values = new ContentValues(); values.put(TodoProvider.KEY_CREATION_DATE, _task.getCreated().getTime()); values.put(TodoProvider.KEY_TASK, _task.getTask()); cr.insert(TodoProvider.CONTENT_URI, values); } public void updateTask(ToDoItem _task) { long tid = _task.getTaskId(); ContentResolver cr = getContentResolver(); ContentValues values = new ContentValues(); values.put(TodoProvider.KEY_TASK, _task.getTask()); cr.update(TodoProvider.CONTENT_URI, values, TodoProvider.KEY_ID + "=" + tid, null); } public void removeTask(long tid) { ContentResolver cr = getContentResolver(); cr.delete(TodoProvider.CONTENT_URI, TodoProvider.KEY_ID + "=" + tid, null); } public Cursor getAllToDoItemsCursor() { ContentResolver cr = getContentResolver(); return cr.query(TodoProvider.CONTENT_URI, null, null, null, null); } } TodoProvider.java: package com.examples.todolist; import android.content.*; import android.database.Cursor; import android.database.SQLException; import android.database.sqlite.SQLiteOpenHelper; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteQueryBuilder; import android.database.sqlite.SQLiteDatabase.CursorFactory; import android.net.Uri; import android.text.TextUtils; import android.util.Log; public class TodoProvider extends ContentProvider { public static final Uri CONTENT_URI = Uri.parse("content://com.examples.provider.todolist/todo"); @Override public boolean onCreate() { Context context = getContext(); todoHelper dbHelper = new todoHelper(context, DATABASE_NAME, null, DATABASE_VERSION); todoDB = dbHelper.getWritableDatabase(); return (todoDB == null) ? false : true; } @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sort) { SQLiteQueryBuilder tb = new SQLiteQueryBuilder(); tb.setTables(TODO_TABLE); // If this is a row query, limit the result set to the passed in row. switch (uriMatcher.match(uri)) { case TASK_ID: tb.appendWhere(KEY_ID + "=" + uri.getPathSegments().get(1)); break; default: break; } // If no sort order is specified sort by date / time String orderBy; if (TextUtils.isEmpty(sort)) { orderBy = KEY_ID; } else { orderBy = sort; } // Apply the query to the underlying database. Cursor c = tb.query(todoDB, projection, selection, selectionArgs, null, null, orderBy); // Register the contexts ContentResolver to be notified if // the cursor result set changes. c.setNotificationUri(getContext().getContentResolver(), uri); // Return a cursor to the query result. return c; } @Override public Uri insert(Uri _uri, ContentValues _initialValues) { // Insert the new row, will return the row number if // successful. long rowID = todoDB.insert(TODO_TABLE, "task", _initialValues); // Return a URI to the newly inserted row on success. if (rowID > 0) { Uri uri = ContentUris.withAppendedId(CONTENT_URI, rowID); getContext().getContentResolver().notifyChange(uri, null); return uri; } throw new SQLException("Failed to insert row into " + _uri); } @Override public int delete(Uri uri, String where, String[] whereArgs) { int count; switch (uriMatcher.match(uri)) { case TASKS: count = todoDB.delete(TODO_TABLE, where, whereArgs); break; case TASK_ID: String segment = uri.getPathSegments().get(1); count = todoDB.delete(TODO_TABLE, KEY_ID + "=" + segment + (!TextUtils.isEmpty(where) ? " AND (" + where + ')' : ""), whereArgs); break; default: throw new IllegalArgumentException("Unsupported URI: " + uri); } getContext().getContentResolver().notifyChange(uri, null); return count; } @Override public int update(Uri uri, ContentValues values, String where, String[] whereArgs) { int count; switch (uriMatcher.match(uri)) { case TASKS: count = todoDB.update(TODO_TABLE, values, where, whereArgs); break; case TASK_ID: String segment = uri.getPathSegments().get(1); count = todoDB.update(TODO_TABLE, values, KEY_ID + "=" + segment + (!TextUtils.isEmpty(where) ? " AND (" + where + ')' : ""), whereArgs); break; default: throw new IllegalArgumentException("Unknown URI " + uri); } getContext().getContentResolver().notifyChange(uri, null); return count; } @Override public String getType(Uri uri) { switch (uriMatcher.match(uri)) { case TASKS: return "vnd.android.cursor.dir/vnd.examples.task"; case TASK_ID: return "vnd.android.cursor.item/vnd.examples.task"; default: throw new IllegalArgumentException("Unsupported URI: " + uri); } } // Create the constants used to differentiate between the different URI // requests. private static final int TASKS = 1; private static final int TASK_ID = 2; private static final UriMatcher uriMatcher; // Allocate the UriMatcher object, where a URI ending in 'tasks' will // correspond to a request for all tasks, and 'tasks' with a // trailing '/[rowID]' will represent a single task row. static { uriMatcher = new UriMatcher(UriMatcher.NO_MATCH); uriMatcher.addURI("com.examples.provider.Todolist", "tasks", TASKS); uriMatcher.addURI("com.examples.provider.Todolist", "tasks/#", TASK_ID); } //The underlying database private SQLiteDatabase todoDB; private static final String TAG = "TodoProvider"; private static final String DATABASE_NAME = "todolist.db"; private static final int DATABASE_VERSION = 1; private static final String TODO_TABLE = "todolist"; // Column Names public static final String KEY_ID = "_id"; public static final String KEY_TASK = "task"; public static final String KEY_CREATION_DATE = "date"; public long insertTask(ToDoItem _task) { // Create a new row of values to insert. ContentValues newTaskValues = new ContentValues(); // Assign values for each row. newTaskValues.put(KEY_TASK, _task.getTask()); newTaskValues.put(KEY_CREATION_DATE, _task.getCreated().getTime()); // Insert the row. return todoDB.insert(TODO_TABLE, null, newTaskValues); } public boolean updateTask(long _rowIndex, String _task) { ContentValues newValue = new ContentValues(); newValue.put(KEY_TASK, _task); return todoDB.update(TODO_TABLE, newValue, KEY_ID + "=" + _rowIndex, null) > 0; } public boolean removeTask(long _rowIndex) { return todoDB.delete(TODO_TABLE, KEY_ID + "=" + _rowIndex, null) > 0; } // Helper class for opening, creating, and managing database version control private static class todoHelper extends SQLiteOpenHelper { private static final String DATABASE_CREATE = "create table " + TODO_TABLE + " (" + KEY_ID + " integer primary key autoincrement, " + KEY_TASK + " TEXT, " + KEY_CREATION_DATE + " INTEGER);"; public todoHelper(Context cn, String name, CursorFactory cf, int ver) { super(cn, name, cf, ver); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(DATABASE_CREATE); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w(TAG, "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); db.execSQL("DROP TABLE IF EXISTS " + TODO_TABLE); onCreate(db); } } } I've omitted the other files as I'm sure they are correct. When I run the program, LogCat shows that the NullPointerException occurs in populateTodoList(), at toDoListCursor = mService.getAllToDoItemsCursor(). mService is the Cursor object returned by TodoService. I've added the service to the Manifest file, but I still cannot find out why it's causing an exception. Thanks in advance.

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  • How to edit item in a listbox shown from reading a .csv file?

    - by Shuvo
    I am working in a project where my application can open a .csv file and read data from it. The .csv file contains the latitude, longitude of places. The application reads data from the file shows it in a static map and display icon on the right places. The application can open multiple file at a time and it opens with a new tab every time. But I am having trouble in couple of cases When I am trying to add a new point to the .csv file opened. I am able to write new point on the same file instead adding a new point data to the existing its replacing others and writing the new point only. I cannot use selectedIndexChange event to perform edit option on the listbox and then save the file. Any direction would be great. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.IO; namespace CourseworkExample { public partial class Form1 : Form { public GPSDataPoint gpsdp; List<GPSDataPoint> data; List<PictureBox> pictures; List<TabPage> tabs; public static int pn = 0; private TabPage currentComponent; private Bitmap bmp1; string[] symbols = { "hospital", "university" }; Image[] symbolImages; ListBox lb = new ListBox(); string name = ""; string path = ""; public Form1() { InitializeComponent(); data = new List<GPSDataPoint>(); pictures = new List<PictureBox>(); tabs = new List<TabPage>(); symbolImages = new Image[symbols.Length]; for (int i = 0; i < 2; i++) { string location = "data/" + symbols[i] + ".png"; symbolImages[i] = Image.FromFile(location); } } private void openToolStripMenuItem_Click(object sender, EventArgs e) { FileDialog ofd = new OpenFileDialog(); string filter = "CSV File (*.csv)|*.csv"; ofd.Filter = filter; DialogResult dr = ofd.ShowDialog(); if (dr.Equals(DialogResult.OK)) { int i = ofd.FileName.LastIndexOf("\\"); name = ofd.FileName; path = ofd.FileName; if (i > 0) { name = ofd.FileName.Substring(i + 1); path = ofd.FileName.Substring(0, i + 1); } TextReader input = new StreamReader(ofd.FileName); string mapName = input.ReadLine(); GPSDataPoint gpsD = new GPSDataPoint(); gpsD.setBounds(input.ReadLine()); string s; while ((s = input.ReadLine()) != null) { gpsD.addWaypoint(s); } input.Close(); TabPage tabPage = new TabPage(); tabPage.Location = new System.Drawing.Point(4, 22); tabPage.Name = "tabPage" + pn; lb.Width = 300; int selectedindex = lb.SelectedIndex; lb.Items.Add(mapName); lb.Items.Add("Bounds"); lb.Items.Add(gpsD.Bounds[0] + " " + gpsD.Bounds[1] + " " + gpsD.Bounds[2] + " " + gpsD.Bounds[3]); lb.Items.Add("Waypoint"); foreach (WayPoint wp in gpsD.DataList) { lb.Items.Add(wp.Name + " " + wp.Latitude + " " + wp.Longitude + " " + wp.Ele + " " + wp.Sym); } tabPage.Controls.Add(lb); pn++; tabPage.Padding = new System.Windows.Forms.Padding(3); tabPage.Size = new System.Drawing.Size(192, 74); tabPage.TabIndex = 0; tabPage.Text = name; tabPage.UseVisualStyleBackColor = true; tabs.Add(tabPage); tabControl1.Controls.Add(tabPage); tabPage = new TabPage(); tabPage.Location = new System.Drawing.Point(4, 22); tabPage.Name = "tabPage" + pn; pn++; tabPage.Padding = new System.Windows.Forms.Padding(3); tabPage.Size = new System.Drawing.Size(192, 74); tabPage.TabIndex = 0; tabPage.Text = mapName; string location = path + mapName; tabPage.UseVisualStyleBackColor = true; tabs.Add(tabPage); PictureBox pb = new PictureBox(); pb.Name = "pictureBox" + pn; pb.Image = Image.FromFile(location); tabControl2.Controls.Add(tabPage); pb.Width = pb.Image.Width; pb.Height = pb.Image.Height; tabPage.Controls.Add(pb); currentComponent = tabPage; tabPage.Width = pb.Width; tabPage.Height = pb.Height; pn++; tabControl2.Width = pb.Width; tabControl2.Height = pb.Height; bmp1 = (Bitmap)pb.Image; int lx, ly; float realWidth = gpsD.Bounds[1] - gpsD.Bounds[3]; float imageW = pb.Image.Width; float dx = imageW * (gpsD.Bounds[1] - gpsD.getWayPoint(0).Longitude) / realWidth; float realHeight = gpsD.Bounds[0] - gpsD.Bounds[2]; float imageH = pb.Image.Height; float dy = imageH * (gpsD.Bounds[0] - gpsD.getWayPoint(0).Latitude) / realHeight; lx = (int)dx; ly = (int)dy; using (Graphics g = Graphics.FromImage(bmp1)) { Rectangle rect = new Rectangle(lx, ly, 20, 20); if (gpsD.getWayPoint(0).Sym.Equals("")) { g.DrawRectangle(new Pen(Color.Red), rect); } else { if (gpsD.getWayPoint(0).Sym.Equals("hospital")) { g.DrawImage(symbolImages[0], rect); } else { if (gpsD.getWayPoint(0).Sym.Equals("university")) { g.DrawImage(symbolImages[1], rect); } } } } pb.Image = bmp1; pb.Invalidate(); } } private void openToolStripMenuItem_Click_1(object sender, EventArgs e) { FileDialog ofd = new OpenFileDialog(); string filter = "CSV File (*.csv)|*.csv"; ofd.Filter = filter; DialogResult dr = ofd.ShowDialog(); if (dr.Equals(DialogResult.OK)) { int i = ofd.FileName.LastIndexOf("\\"); name = ofd.FileName; path = ofd.FileName; if (i > 0) { name = ofd.FileName.Substring(i + 1); path = ofd.FileName.Substring(0, i + 1); } TextReader input = new StreamReader(ofd.FileName); string mapName = input.ReadLine(); GPSDataPoint gpsD = new GPSDataPoint(); gpsD.setBounds(input.ReadLine()); string s; while ((s = input.ReadLine()) != null) { gpsD.addWaypoint(s); } input.Close(); TabPage tabPage = new TabPage(); tabPage.Location = new System.Drawing.Point(4, 22); tabPage.Name = "tabPage" + pn; ListBox lb = new ListBox(); lb.Width = 300; lb.Items.Add(mapName); lb.Items.Add("Bounds"); lb.Items.Add(gpsD.Bounds[0] + " " + gpsD.Bounds[1] + " " + gpsD.Bounds[2] + " " + gpsD.Bounds[3]); lb.Items.Add("Waypoint"); foreach (WayPoint wp in gpsD.DataList) { lb.Items.Add(wp.Name + " " + wp.Latitude + " " + wp.Longitude + " " + wp.Ele + " " + wp.Sym); } tabPage.Controls.Add(lb); pn++; tabPage.Padding = new System.Windows.Forms.Padding(3); tabPage.Size = new System.Drawing.Size(192, 74); tabPage.TabIndex = 0; tabPage.Text = name; tabPage.UseVisualStyleBackColor = true; tabs.Add(tabPage); tabControl1.Controls.Add(tabPage); tabPage = new TabPage(); tabPage.Location = new System.Drawing.Point(4, 22); tabPage.Name = "tabPage" + pn; pn++; tabPage.Padding = new System.Windows.Forms.Padding(3); tabPage.Size = new System.Drawing.Size(192, 74); tabPage.TabIndex = 0; tabPage.Text = mapName; string location = path + mapName; tabPage.UseVisualStyleBackColor = true; tabs.Add(tabPage); PictureBox pb = new PictureBox(); pb.Name = "pictureBox" + pn; pb.Image = Image.FromFile(location); tabControl2.Controls.Add(tabPage); pb.Width = pb.Image.Width; pb.Height = pb.Image.Height; tabPage.Controls.Add(pb); currentComponent = tabPage; tabPage.Width = pb.Width; tabPage.Height = pb.Height; pn++; tabControl2.Width = pb.Width; tabControl2.Height = pb.Height; bmp1 = (Bitmap)pb.Image; int lx, ly; float realWidth = gpsD.Bounds[1] - gpsD.Bounds[3]; float imageW = pb.Image.Width; float dx = imageW * (gpsD.Bounds[1] - gpsD.getWayPoint(0).Longitude) / realWidth; float realHeight = gpsD.Bounds[0] - gpsD.Bounds[2]; float imageH = pb.Image.Height; float dy = imageH * (gpsD.Bounds[0] - gpsD.getWayPoint(0).Latitude) / realHeight; lx = (int)dx; ly = (int)dy; using (Graphics g = Graphics.FromImage(bmp1)) { Rectangle rect = new Rectangle(lx, ly, 20, 20); if (gpsD.getWayPoint(0).Sym.Equals("")) { g.DrawRectangle(new Pen(Color.Red), rect); } else { if (gpsD.getWayPoint(0).Sym.Equals("hospital")) { g.DrawImage(symbolImages[0], rect); } else { if (gpsD.getWayPoint(0).Sym.Equals("university")) { g.DrawImage(symbolImages[1], rect); } } } } pb.Image = bmp1; pb.Invalidate(); MessageBox.Show(data.ToString()); } } private void exitToolStripMenuItem_Click(object sender, EventArgs e) { this.Close(); } private void addBtn_Click(object sender, EventArgs e) { string wayName = nameTxtBox.Text; float wayLat = Convert.ToSingle(latTxtBox.Text); float wayLong = Convert.ToSingle(longTxtBox.Text); float wayEle = Convert.ToSingle(elevTxtBox.Text); WayPoint wp = new WayPoint(wayName, wayLat, wayLong, wayEle); GPSDataPoint gdp = new GPSDataPoint(); data = new List<GPSDataPoint>(); gdp.Add(wp); lb.Items.Add(wp.Name + " " + wp.Latitude + " " + wp.Longitude + " " + wp.Ele + " " + wp.Sym); lb.Refresh(); StreamWriter sr = new StreamWriter(name); sr.Write(lb); sr.Close(); DialogResult result = MessageBox.Show("Save in New File?","Save", MessageBoxButtons.YesNo); if (result == DialogResult.Yes) { SaveFileDialog saveDialog = new SaveFileDialog(); saveDialog.FileName = "default.csv"; DialogResult saveResult = saveDialog.ShowDialog(); if (saveResult == DialogResult.OK) { sr = new StreamWriter(saveDialog.FileName, true); sr.WriteLine(wayName + "," + wayLat + "," + wayLong + "," + wayEle); sr.Close(); } } else { // sr = new StreamWriter(name, true); // sr.WriteLine(wayName + "," + wayLat + "," + wayLong + "," + wayEle); sr.Close(); } MessageBox.Show(name + path); } } } GPSDataPoint.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; namespace CourseworkExample { public class GPSDataPoint { private float[] bounds; private List<WayPoint> dataList; public GPSDataPoint() { dataList = new List<WayPoint>(); } internal void setBounds(string p) { string[] b = p.Split(','); bounds = new float[b.Length]; for (int i = 0; i < b.Length; i++) { bounds[i] = Convert.ToSingle(b[i]); } } public float[] Bounds { get { return bounds; } } internal void addWaypoint(string s) { WayPoint wp = new WayPoint(s); dataList.Add(wp); } public WayPoint getWayPoint(int i) { if (i < dataList.Count) { return dataList[i]; } else return null; } public List<WayPoint> DataList { get { return dataList; } } internal void Add(WayPoint wp) { dataList.Add(wp); } } } WayPoint.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace CourseworkExample { public class WayPoint { private string name; private float ele; private float latitude; private float longitude; private string sym; public WayPoint(string name, float latitude, float longitude, float elevation) { this.name = name; this.latitude = latitude; this.longitude = longitude; this.ele = elevation; } public WayPoint() { name = "no name"; ele = 3.5F; latitude = 3.5F; longitude = 0.0F; sym = "no symbol"; } public WayPoint(string s) { string[] bits = s.Split(','); name = bits[0]; longitude = Convert.ToSingle(bits[2]); latitude = Convert.ToSingle(bits[1]); if (bits.Length > 4) sym = bits[4]; else sym = ""; try { ele = Convert.ToSingle(bits[3]); } catch (Exception e) { ele = 0.0f; } } public float Longitude { get { return longitude; } set { longitude = value; } } public float Latitude { get { return latitude; } set { latitude = value; } } public float Ele { get { return ele; } set { ele = value; } } public string Name { get { return name; } set { name = value; } } public string Sym { get { return sym; } set { sym = value; } } } } .csv file data birthplace.png 51.483788,-0.351906,51.460745,-0.302982 Born Here,51.473805,-0.32532,-,hospital Danced here,51,483805,-0.32532,-,hospital

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  • Get data from MySQL to Android application

    - by Mona
    I want to get data from MySQL database using PHP and display it in Android activity. I code it and pass JSON Array but there is a problem i dont know how to connect to server and my all database is on local server. I code it Kindly tell me where i go wrong so I can get exact results. I'll be very thankful to you. My PHP code is: <?php $response = array(); require_once __DIR__ . '/db_connect.php'; $db = new DB_CONNECT(); if (isset($_GET["cid"])) { $cid = $_GET['cid']; // get a product from products table $result = mysql_query("SELECT *FROM my_task WHERE cid = $cid"); if (!empty($result)) { // check for empty result if (mysql_num_rows($result) > 0) { $result = mysql_fetch_array($result); $task = array(); $task["cid"] = $result["cid"]; $task["cus_name"] = $result["cus_name"]; $task["contact_number"] = $result["contact_number"]; $task["ticket_no"] = $result["ticket_no"]; $task["task_detail"] = $result["task_detail"]; // success $response["success"] = 1; // user node $response["task"] = array(); array_push($response["my_task"], $task); // echoing JSON response echo json_encode($response); } else { // no task found $response["success"] = 0; $response["message"] = "No product found"; // echo no users JSON echo json_encode($response); } } else { // no task found $response["success"] = 0; $response["message"] = "No product found"; echo json_encode($response); } } else { $response["success"] = 0; $response["message"] = "Required field(s) is missing"; // echoing JSON response echo json_encode($response);} ?> My Android code is: public class My_Task extends Activity { TextView cus_name_txt, contact_no_txt, ticket_no_txt, task_detail_txt; EditText attend_by_txtbx, cus_name_txtbx, contact_no_txtbx, ticket_no_txtbx, task_detail_txtbx; Button btnSave; Button btnDelete; String cid; // Progress Dialog private ProgressDialog tDialog; // Creating JSON Parser object JSONParser jParser = new JSONParser(); ArrayList<HashMap<String, String>> my_taskList; // single task url private static final String url_read_mytask = "http://198.168.0.29/mobile/read_My_Task.php"; // url to update product private static final String url_update_mytask = "http://198.168.0.29/mobile/update_mytask.php"; // url to delete product private static final String url_delete_mytask = "http://198.168.0.29/mobile/delete_mytask.php"; // JSON Node names private static String TAG_SUCCESS = "success"; private static String TAG_MYTASK = "my_task"; private static String TAG_CID = "cid"; private static String TAG_NAME = "cus_name"; private static String TAG_CONTACT = "contact_number"; private static String TAG_TICKET = "ticket_no"; private static String TAG_TASKDETAIL = "task_detail"; private static String attend_by_txt; // task JSONArray JSONArray my_task = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_task); cus_name_txt = (TextView) findViewById(R.id.cus_name_txt); contact_no_txt = (TextView)findViewById(R.id.contact_no_txt); ticket_no_txt = (TextView)findViewById(R.id.ticket_no_txt); task_detail_txt = (TextView)findViewById(R.id.task_detail_txt); attend_by_txtbx = (EditText)findViewById(R.id.attend_by_txt); attend_by_txtbx.setText(My_Task.attend_by_txt); Spinner severity = (Spinner) findViewById(R.id.severity_spinner); // Create an ArrayAdapter using the string array and a default spinner layout ArrayAdapter<CharSequence> adapter3 = ArrayAdapter.createFromResource(this, R.array.Severity_array, android.R.layout.simple_dropdown_item_1line); // Specify the layout to use when the list of choices appears adapter3.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // Apply the adapter to the spinner severity.setAdapter(adapter3); // save button btnSave = (Button) findViewById(R.id.btnSave); btnDelete = (Button) findViewById(R.id.btnDelete); // getting product details from intent Intent i = getIntent(); // getting product id (pid) from intent cid = i.getStringExtra(TAG_CID); // Getting complete product details in background thread new GetProductDetails().execute(); // save button click event btnSave.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View arg0) { // starting background task to update product new SaveProductDetails().execute(); } }); // Delete button click event btnDelete.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View arg0) { // deleting product in background thread new DeleteProduct().execute(); } }); } /** * Background Async Task to Get complete product details * */ class GetProductDetails extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); tDialog = new ProgressDialog(My_Task.this); tDialog.setMessage("Loading task details. Please wait..."); tDialog.setIndeterminate(false); tDialog.setCancelable(true); tDialog.show(); } /** * Getting product details in background thread * */ protected String doInBackground(String... params) { // updating UI from Background Thread runOnUiThread(new Runnable() { public void run() { // Check for success tag int success; try { // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("cid", cid)); // getting product details by making HTTP request // Note that product details url will use GET request JSONObject json = JSONParser.makeHttpRequest( url_read_mytask, "GET", params); // check your log for json response Log.d("Single Task Details", json.toString()); // json success tag success = json.getInt(TAG_SUCCESS); if (success == 1) { // successfully received product details JSONArray my_taskObj = json .getJSONArray(TAG_MYTASK); // JSON Array // get first product object from JSON Array JSONObject my_task = my_taskObj.getJSONObject(0); // task with this cid found // Edit Text // display task data in EditText cus_name_txtbx = (EditText) findViewById(R.id.cus_name_txt); cus_name_txtbx.setText(my_task.getString(TAG_NAME)); contact_no_txtbx = (EditText) findViewById(R.id.contact_no_txt); contact_no_txtbx.setText(my_task.getString(TAG_CONTACT)); ticket_no_txtbx = (EditText) findViewById(R.id.ticket_no_txt); ticket_no_txtbx.setText(my_task.getString(TAG_TICKET)); task_detail_txtbx = (EditText) findViewById(R.id.task_detail_txt); task_detail_txtbx.setText(my_task.getString(TAG_TASKDETAIL)); } else { // task with cid not found } } catch (JSONException e) { e.printStackTrace(); } } }); return null; } /** * After completing background task Dismiss the progress dialog * **/ protected void onPostExecute(String file_url) { // dismiss the dialog once got all details tDialog.dismiss(); } } /** * Background Async Task to Save product Details * */ class SaveProductDetails extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); tDialog = new ProgressDialog(My_Task.this); tDialog.setMessage("Saving task ..."); tDialog.setIndeterminate(false); tDialog.setCancelable(true); tDialog.show(); } /** * Saving product * */ protected String doInBackground(String... args) { // getting updated data from EditTexts String cus_name = cus_name_txt.getText().toString(); String contact_no = contact_no_txt.getText().toString(); String ticket_no = ticket_no_txt.getText().toString(); String task_detail = task_detail_txt.getText().toString(); // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair(TAG_CID, cid)); params.add(new BasicNameValuePair(TAG_NAME, cus_name)); params.add(new BasicNameValuePair(TAG_CONTACT, contact_no)); params.add(new BasicNameValuePair(TAG_TICKET, ticket_no)); params.add(new BasicNameValuePair(TAG_TASKDETAIL, task_detail)); // sending modified data through http request // Notice that update product url accepts POST method JSONObject json = JSONParser.makeHttpRequest(url_update_mytask, "POST", params); // check json success tag try { int success = json.getInt(TAG_SUCCESS); if (success == 1) { // successfully updated Intent i = getIntent(); // send result code 100 to notify about product update setResult(100, i); finish(); } else { // failed to update product } } catch (JSONException e) { e.printStackTrace(); } return null; } /** * After completing background task Dismiss the progress dialog * **/ protected void onPostExecute(String file_url) { // dismiss the dialog once product uupdated tDialog.dismiss(); } } /***************************************************************** * Background Async Task to Delete Product * */ class DeleteProduct extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); tDialog = new ProgressDialog(My_Task.this); tDialog.setMessage("Deleting Product..."); tDialog.setIndeterminate(false); tDialog.setCancelable(true); tDialog.show(); } /** * Deleting product * */ protected String doInBackground(String... args) { // Check for success tag int success; try { // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("cid", cid)); // getting product details by making HTTP request JSONObject json = JSONParser.makeHttpRequest( url_delete_mytask, "POST", params); // check your log for json response Log.d("Delete Task", json.toString()); // json success tag success = json.getInt(TAG_SUCCESS); if (success == 1) { // product successfully deleted // notify previous activity by sending code 100 Intent i = getIntent(); // send result code 100 to notify about product deletion setResult(100, i); finish(); } } catch (JSONException e) { e.printStackTrace(); } return null; } /** * After completing background task Dismiss the progress dialog * **/ protected void onPostExecute(String file_url) { // dismiss the dialog once product deleted tDialog.dismiss(); } } public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) { // An item was selected. You can retrieve the selected item using // parent.getItemAtPosition(pos) } public void onNothingSelected(AdapterView<?> parent) { // Another interface callback } } My JSONParser code is: public class JSONParser { static InputStream is = null; static JSONObject jObj = null; static String json = ""; // constructor public JSONParser() { } // function get json from url // by making HTTP POST or GET mehtod public static JSONObject makeHttpRequest(String url, String method, List<NameValuePair> params) { // Making HTTP request try { // check for request method if(method == "POST"){ // request method is POST // defaultHttpClient DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); httpPost.setEntity(new UrlEncodedFormEntity(params)); HttpResponse httpResponse = httpClient.execute(httpPost); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); }else if(method == "GET"){ // request method is GET DefaultHttpClient httpClient = new DefaultHttpClient(); String paramString = URLEncodedUtils.format(params, "utf-8"); url += "?" + paramString; HttpGet httpGet = new HttpGet(url); HttpResponse httpResponse = httpClient.execute(httpGet); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); } } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } try { BufferedReader reader = new BufferedReader(new InputStreamReader( is, "iso-8859-1"), 8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } is.close(); json = sb.toString(); } catch (Exception e) { Log.e("Buffer Error", "Error converting result " + e.toString()); } // try parse the string to a JSON object try { jObj = new JSONObject(json); } catch (JSONException e) { Log.e("JSON Parser", "Error parsing data " + e.toString()); } // return JSON String return jObj; my all database is in localhost and it is not opening an activity. displays an error "Stopped unexpectedly":( How can i get exact results. Kindly guide me

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  • Steganography Experiment - Trouble hiding message bits in DCT coefficients

    - by JohnHankinson
    I have an application requiring me to be able to embed loss-less data into an image. As such I've been experimenting with steganography, specifically via modification of DCT coefficients as the method I select, apart from being loss-less must also be relatively resilient against format conversion, scaling/DSP etc. From the research I've done thus far this method seems to be the best candidate. I've seen a number of papers on the subject which all seem to neglect specific details (some neglect to mention modification of 0 coefficients, or modification of AC coefficient etc). After combining the findings and making a few modifications of my own which include: 1) Using a more quantized version of the DCT matrix to ensure we only modify coefficients that would still be present should the image be JPEG'ed further or processed (I'm using this in place of simply following a zig-zag pattern). 2) I'm modifying bit 4 instead of the LSB and then based on what the original bit value was adjusting the lower bits to minimize the difference. 3) I'm only modifying the blue channel as it should be the least visible. This process must modify the actual image and not the DCT values stored in file (like jsteg) as there is no guarantee the file will be a JPEG, it may also be opened and re-saved at a later stage in a different format. For added robustness I've included the message multiple times and use the bits that occur most often, I had considered using a QR code as the message data or simply applying the reed-solomon error correction, but for this simple application and given that the "message" in question is usually going to be between 10-32 bytes I have plenty of room to repeat it which should provide sufficient redundancy to recover the true bits. No matter what I do I don't seem to be able to recover the bits at the decode stage. I've tried including / excluding various checks (even if it degrades image quality for the time being). I've tried using fixed point vs. double arithmetic, moving the bit to encode, I suspect that the message bits are being lost during the IDCT back to image. Any thoughts or suggestions on how to get this working would be hugely appreciated. (PS I am aware that the actual DCT/IDCT could be optimized from it's naive On4 operation using row column algorithm, or an FDCT like AAN, but for now it just needs to work :) ) Reference Papers: http://www.lokminglui.com/dct.pdf http://arxiv.org/ftp/arxiv/papers/1006/1006.1186.pdf Code for the Encode/Decode process in C# below: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Drawing.Imaging; using System.Drawing; namespace ImageKey { public class Encoder { public const int HIDE_BIT_POS = 3; // use bit position 4 (1 << 3). public const int HIDE_COUNT = 16; // Number of times to repeat the message to avoid error. // JPEG Standard Quantization Matrix. // (to get higher quality multiply by (100-quality)/50 .. // for lower than 50 multiply by 50/quality. Then round to integers and clip to ensure only positive integers. public static double[] Q = {16,11,10,16,24,40,51,61, 12,12,14,19,26,58,60,55, 14,13,16,24,40,57,69,56, 14,17,22,29,51,87,80,62, 18,22,37,56,68,109,103,77, 24,35,55,64,81,104,113,92, 49,64,78,87,103,121,120,101, 72,92,95,98,112,100,103,99}; // Maximum qauality quantization matrix (if all 1's doesn't modify coefficients at all). public static double[] Q2 = {1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1}; public static Bitmap Encode(Bitmap b, string key) { Bitmap response = new Bitmap(b.Width, b.Height, PixelFormat.Format32bppArgb); uint imgWidth = ((uint)b.Width) & ~((uint)7); // Maximum usable X resolution (divisible by 8). uint imgHeight = ((uint)b.Height) & ~((uint)7); // Maximum usable Y resolution (divisible by 8). // Start be transferring the unmodified image portions. // As we'll be using slightly less width/height for the encoding process we'll need the edges to be populated. for (int y = 0; y < b.Height; y++) for (int x = 0; x < b.Width; x++) { if( (x >= imgWidth && x < b.Width) || (y>=imgHeight && y < b.Height)) response.SetPixel(x, y, b.GetPixel(x, y)); } // Setup the counters and byte data for the message to encode. StringBuilder sb = new StringBuilder(); for(int i=0;i<HIDE_COUNT;i++) sb.Append(key); byte[] codeBytes = System.Text.Encoding.ASCII.GetBytes(sb.ToString()); int bitofs = 0; // Current bit position we've encoded too. int totalBits = (codeBytes.Length * 8); // Total number of bits to encode. for (int y = 0; y < imgHeight; y += 8) { for (int x = 0; x < imgWidth; x += 8) { int[] redData = GetRedChannelData(b, x, y); int[] greenData = GetGreenChannelData(b, x, y); int[] blueData = GetBlueChannelData(b, x, y); int[] newRedData; int[] newGreenData; int[] newBlueData; if (bitofs < totalBits) { double[] redDCT = DCT(ref redData); double[] greenDCT = DCT(ref greenData); double[] blueDCT = DCT(ref blueData); int[] redDCTI = Quantize(ref redDCT, ref Q2); int[] greenDCTI = Quantize(ref greenDCT, ref Q2); int[] blueDCTI = Quantize(ref blueDCT, ref Q2); int[] blueDCTC = Quantize(ref blueDCT, ref Q); HideBits(ref blueDCTI, ref blueDCTC, ref bitofs, ref totalBits, ref codeBytes); double[] redDCT2 = DeQuantize(ref redDCTI, ref Q2); double[] greenDCT2 = DeQuantize(ref greenDCTI, ref Q2); double[] blueDCT2 = DeQuantize(ref blueDCTI, ref Q2); newRedData = IDCT(ref redDCT2); newGreenData = IDCT(ref greenDCT2); newBlueData = IDCT(ref blueDCT2); } else { newRedData = redData; newGreenData = greenData; newBlueData = blueData; } MapToRGBRange(ref newRedData); MapToRGBRange(ref newGreenData); MapToRGBRange(ref newBlueData); for(int dy=0;dy<8;dy++) { for(int dx=0;dx<8;dx++) { int col = (0xff<<24) + (newRedData[dx+(dy*8)]<<16) + (newGreenData[dx+(dy*8)]<<8) + (newBlueData[dx+(dy*8)]); response.SetPixel(x+dx,y+dy,Color.FromArgb(col)); } } } } if (bitofs < totalBits) throw new Exception("Failed to encode data - insufficient cover image coefficients"); return (response); } public static void HideBits(ref int[] DCTMatrix, ref int[] CMatrix, ref int bitofs, ref int totalBits, ref byte[] codeBytes) { int tempValue = 0; for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { if ( (u != 0 || v != 0) && CMatrix[v+(u*8)] != 0 && DCTMatrix[v+(u*8)] != 0) { if (bitofs < totalBits) { tempValue = DCTMatrix[v + (u * 8)]; int bytePos = (bitofs) >> 3; int bitPos = (bitofs) % 8; byte mask = (byte)(1 << bitPos); byte value = (byte)((codeBytes[bytePos] & mask) >> bitPos); // 0 or 1. if (value == 0) { int a = DCTMatrix[v + (u * 8)] & (1 << HIDE_BIT_POS); if (a != 0) DCTMatrix[v + (u * 8)] |= (1 << HIDE_BIT_POS) - 1; DCTMatrix[v + (u * 8)] &= ~(1 << HIDE_BIT_POS); } else if (value == 1) { int a = DCTMatrix[v + (u * 8)] & (1 << HIDE_BIT_POS); if (a == 0) DCTMatrix[v + (u * 8)] &= ~((1 << HIDE_BIT_POS) - 1); DCTMatrix[v + (u * 8)] |= (1 << HIDE_BIT_POS); } if (DCTMatrix[v + (u * 8)] != 0) bitofs++; else DCTMatrix[v + (u * 8)] = tempValue; } } } } } public static void MapToRGBRange(ref int[] data) { for(int i=0;i<data.Length;i++) { data[i] += 128; if(data[i] < 0) data[i] = 0; else if(data[i] > 255) data[i] = 255; } } public static int[] GetRedChannelData(Bitmap b, int sx, int sy) { int[] data = new int[8 * 8]; for (int y = sy; y < (sy + 8); y++) { for (int x = sx; x < (sx + 8); x++) { uint col = (uint)b.GetPixel(x,y).ToArgb(); data[(x - sx) + ((y - sy) * 8)] = (int)((col >> 16) & 0xff) - 128; } } return (data); } public static int[] GetGreenChannelData(Bitmap b, int sx, int sy) { int[] data = new int[8 * 8]; for (int y = sy; y < (sy + 8); y++) { for (int x = sx; x < (sx + 8); x++) { uint col = (uint)b.GetPixel(x, y).ToArgb(); data[(x - sx) + ((y - sy) * 8)] = (int)((col >> 8) & 0xff) - 128; } } return (data); } public static int[] GetBlueChannelData(Bitmap b, int sx, int sy) { int[] data = new int[8 * 8]; for (int y = sy; y < (sy + 8); y++) { for (int x = sx; x < (sx + 8); x++) { uint col = (uint)b.GetPixel(x, y).ToArgb(); data[(x - sx) + ((y - sy) * 8)] = (int)((col >> 0) & 0xff) - 128; } } return (data); } public static int[] Quantize(ref double[] DCTMatrix, ref double[] Q) { int[] DCTMatrixOut = new int[8*8]; for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { DCTMatrixOut[v + (u * 8)] = (int)Math.Round(DCTMatrix[v + (u * 8)] / Q[v + (u * 8)]); } } return(DCTMatrixOut); } public static double[] DeQuantize(ref int[] DCTMatrix, ref double[] Q) { double[] DCTMatrixOut = new double[8*8]; for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { DCTMatrixOut[v + (u * 8)] = (double)DCTMatrix[v + (u * 8)] * Q[v + (u * 8)]; } } return(DCTMatrixOut); } public static double[] DCT(ref int[] data) { double[] DCTMatrix = new double[8 * 8]; for (int v = 0; v < 8; v++) { for (int u = 0; u < 8; u++) { double cu = 1; if (u == 0) cu = (1.0 / Math.Sqrt(2.0)); double cv = 1; if (v == 0) cv = (1.0 / Math.Sqrt(2.0)); double sum = 0.0; for (int y = 0; y < 8; y++) { for (int x = 0; x < 8; x++) { double s = data[x + (y * 8)]; double dctVal = Math.Cos((2 * y + 1) * v * Math.PI / 16) * Math.Cos((2 * x + 1) * u * Math.PI / 16); sum += s * dctVal; } } DCTMatrix[u + (v * 8)] = (0.25 * cu * cv * sum); } } return (DCTMatrix); } public static int[] IDCT(ref double[] DCTMatrix) { int[] Matrix = new int[8 * 8]; for (int y = 0; y < 8; y++) { for (int x = 0; x < 8; x++) { double sum = 0; for (int v = 0; v < 8; v++) { for (int u = 0; u < 8; u++) { double cu = 1; if (u == 0) cu = (1.0 / Math.Sqrt(2.0)); double cv = 1; if (v == 0) cv = (1.0 / Math.Sqrt(2.0)); double idctVal = (cu * cv) / 4.0 * Math.Cos((2 * y + 1) * v * Math.PI / 16) * Math.Cos((2 * x + 1) * u * Math.PI / 16); sum += (DCTMatrix[u + (v * 8)] * idctVal); } } Matrix[x + (y * 8)] = (int)Math.Round(sum); } } return (Matrix); } } public class Decoder { public static string Decode(Bitmap b, int expectedLength) { expectedLength *= Encoder.HIDE_COUNT; uint imgWidth = ((uint)b.Width) & ~((uint)7); // Maximum usable X resolution (divisible by 8). uint imgHeight = ((uint)b.Height) & ~((uint)7); // Maximum usable Y resolution (divisible by 8). // Setup the counters and byte data for the message to decode. byte[] codeBytes = new byte[expectedLength]; byte[] outBytes = new byte[expectedLength / Encoder.HIDE_COUNT]; int bitofs = 0; // Current bit position we've decoded too. int totalBits = (codeBytes.Length * 8); // Total number of bits to decode. for (int y = 0; y < imgHeight; y += 8) { for (int x = 0; x < imgWidth; x += 8) { int[] blueData = ImageKey.Encoder.GetBlueChannelData(b, x, y); double[] blueDCT = ImageKey.Encoder.DCT(ref blueData); int[] blueDCTI = ImageKey.Encoder.Quantize(ref blueDCT, ref Encoder.Q2); int[] blueDCTC = ImageKey.Encoder.Quantize(ref blueDCT, ref Encoder.Q); if (bitofs < totalBits) GetBits(ref blueDCTI, ref blueDCTC, ref bitofs, ref totalBits, ref codeBytes); } } bitofs = 0; for (int i = 0; i < (expectedLength / Encoder.HIDE_COUNT) * 8; i++) { int bytePos = (bitofs) >> 3; int bitPos = (bitofs) % 8; byte mask = (byte)(1 << bitPos); List<int> values = new List<int>(); int zeroCount = 0; int oneCount = 0; for (int j = 0; j < Encoder.HIDE_COUNT; j++) { int val = (codeBytes[bytePos + ((expectedLength / Encoder.HIDE_COUNT) * j)] & mask) >> bitPos; values.Add(val); if (val == 0) zeroCount++; else oneCount++; } if (oneCount >= zeroCount) outBytes[bytePos] |= mask; bitofs++; values.Clear(); } return (System.Text.Encoding.ASCII.GetString(outBytes)); } public static void GetBits(ref int[] DCTMatrix, ref int[] CMatrix, ref int bitofs, ref int totalBits, ref byte[] codeBytes) { for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { if ((u != 0 || v != 0) && CMatrix[v + (u * 8)] != 0 && DCTMatrix[v + (u * 8)] != 0) { if (bitofs < totalBits) { int bytePos = (bitofs) >> 3; int bitPos = (bitofs) % 8; byte mask = (byte)(1 << bitPos); int value = DCTMatrix[v + (u * 8)] & (1 << Encoder.HIDE_BIT_POS); if (value != 0) codeBytes[bytePos] |= mask; bitofs++; } } } } } } } UPDATE: By switching to using a QR Code as the source message and swapping a pair of coefficients in each block instead of bit manipulation I've been able to get the message to survive the transform. However to get the message to come through without corruption I have to adjust both coefficients as well as swap them. For example swapping (3,4) and (4,3) in the DCT matrix and then respectively adding 8 and subtracting 8 as an arbitrary constant seems to work. This survives a re-JPEG'ing of 96 but any form of scaling/cropping destroys the message again. I was hoping that by operating on mid to low frequency values that the message would be preserved even under some light image manipulation.

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  • Why my application ask for a codec to pla the MVI(.MOV) video files while i can play them on WMP and QuickTime?

    - by Daniel Lip
    I have an application i did some time ago when im loading the video file its ok when trying to play/use the file im getting the messageBox message say that its need a codec to use gspot or search the internet. Wehn im playing this files on my hard disk with Windows Media Play or either QuickTime there is no problems. The Video files for example name are: MVI_2483 in the file name properties i see its type: Quick Time Movie (.MOV) In my application im using DirectShowLib-2005.dll this is the class im using in my case to extract the video file im using it in my application to extract only lightnings from the video file name. In Form1 i have a button click event that just starting the action: private void button8_Click(object sender, EventArgs e) { viewToolStripMenuItem.Enabled = false; fileToolStripMenuItem.Enabled = false; button2.Enabled = false; label14.Visible = false; label15.Visible = false; label21.Visible = false; label22.Visible = false; label24.Visible = false; label25.Visible = false; ExtractAutomatic = true; DirectoryInfo info = new DirectoryInfo(_videoFile); string dirName = info.Name; automaticModeDirectory = dirName + "_Automatic"; subDirectoryName = _outputDir + "\\" + automaticModeDirectory; if (secondPass == true) { Start(true); } Start(false); } This is the function start in Form1: private void Start(bool secondpass) { setpicture(-1); if (Directory.Exists(_outputDir) && secondpass == false) { } else { Directory.CreateDirectory(_outputDir); } if (ExtractAutomatic == true) { string subDirectory_Automatic_Name = _outputDir + "\\" + automaticModeDirectory; Directory.CreateDirectory(subDirectory_Automatic_Name); f = new WmvAdapter(_videoFile, Path.Combine(subDirectory_Automatic_Name)); } else { string subDirectory_Manual_Name; if (Directory.Exists(subDirectoryName)) { subDirectory_Manual_Name = subDirectoryName; f = new WmvAdapter(_videoFile, Path.Combine(subDirectory_Manual_Name)); } else { subDirectory_Manual_Name = _outputDir + "\\" + averagesListTextFileDirectory + "_Manual"; Directory.CreateDirectory(subDirectory_Manual_Name); f = new WmvAdapter(_videoFile, Path.Combine(subDirectory_Manual_Name)); } } button1.Enabled = false; f.Secondpass = secondpass; f.FramesToSave = _fts; f.FrameCountAvailable += new WmvAdapter.FrameCountEventHandler(f_FrameCountAvailable); f.StatusChanged += new WmvAdapter.EventHandler(f_StatusChanged); f.ProgressChanged += new WmvAdapter.ProgressEventHandler(f_ProgressChanged); this.Text = "Processing Please Wait..."; label5.ForeColor = Color.Green; label5.Text = "Processing Please Wait"; button8.Enabled = false; button5.Enabled = false; label5.Visible = true; pictureBox1.Image = Lightnings_Extractor.Properties.Resources.Weather_Michmoret; Hrs = 0; //number of hours Min = 0; //number of Minutes Sec = 0; //number of Sec timeElapsed = 0; label10.Text = "00:00:00"; label11.Visible = false; label12.Visible = false; label9.Visible = false; label8.Visible = false; this.button1.Enabled = false; myTrackPanelss1.trackBar1.Enabled = false; this.checkBox2.Enabled = false; this.checkBox1.Enabled = false; numericUpDown1.Enabled = false; timer1.Start(); label2.Text = ""; label1.Visible = true; label2.Visible = true; label3.Visible = true; label4.Visible = true; f.Start(); } And this is the class wich is not my oqn class i just just defined it in some places wich making the problem: using System; using System.Diagnostics; using System.Drawing; using System.Drawing.Imaging; using System.IO; using System.Runtime.InteropServices; using DirectShowLib; using System.Collections.Generic; using Extracting_Frames; using System.Windows.Forms; namespace Polkan.DataSource { internal class WmvAdapter : ISampleGrabberCB, IDisposable { #region Fields_Properties_and_Events bool dis = false; int count = 0; const string fileName = @"d:\histogramValues.dat"; private IFilterGraph2 _filterGraph; private IMediaControl _mediaCtrl; private IMediaEvent _mediaEvent; private int _width; private int _height; private readonly string _outFolder; private int _frameId; //better use a custom EventHandler that passes the results of the action to the subscriber. public delegate void EventHandler(object sender, EventArgs e); public event EventHandler StatusChanged; public delegate void FrameCountEventHandler(object sender, FrameCountEventArgs e); public event FrameCountEventHandler FrameCountAvailable; public delegate void ProgressEventHandler(object sender, ProgressEventArgs e); public event ProgressEventHandler ProgressChanged; private IMediaSeeking _mSeek; private long _duration = 0; private long _avgFrameTime = 0; //just save the averages to a List (not to fs) public List<double> AveragesList { get; set; } public List<long> histogramValuesList; public bool Secondpass { get; set; } public List<int> FramesToSave { get; set; } #endregion #region Constructors and Destructors public WmvAdapter(string file, string outFolder) { _outFolder = outFolder; try { SetupGraph(file); } catch { Dispose(); MessageBox.Show("A codec is required to load this video file. Please use http://www.headbands.com/gspot/ or search the web for the correct codec"); } } ~WmvAdapter() { CloseInterfaces(); } #endregion public void Dispose() { CloseInterfaces(); } public void Start() { EstimateFrameCount(); int hr = _mediaCtrl.Run(); WaitUntilDone(); DsError.ThrowExceptionForHR(hr); } public void WaitUntilDone() { int hr; const int eAbort = unchecked((int)0x80004004); do { System.Windows.Forms.Application.DoEvents(); EventCode evCode; if (dis == true) { return; } hr = _mediaEvent.WaitForCompletion(100, out evCode); }while (hr == eAbort); DsError.ThrowExceptionForHR(hr); OnStatusChanged(); } //Edit: added events protected virtual void OnStatusChanged() { if (StatusChanged != null) StatusChanged(this, new EventArgs()); } protected virtual void OnFrameCountAvailable(long frameCount) { if (FrameCountAvailable != null) FrameCountAvailable(this, new FrameCountEventArgs() { FrameCount = frameCount }); } protected virtual void OnProgressChanged(int frameID) { if (ProgressChanged != null) ProgressChanged(this, new ProgressEventArgs() { FrameID = frameID }); } /// <summary> build the capture graph for grabber. </summary> private void SetupGraph(string file) { ISampleGrabber sampGrabber = null; IBaseFilter capFilter = null; IBaseFilter nullrenderer = null; _filterGraph = (IFilterGraph2)new FilterGraph(); _mediaCtrl = (IMediaControl)_filterGraph; _mediaEvent = (IMediaEvent)_filterGraph; _mSeek = (IMediaSeeking)_filterGraph; var mediaFilt = (IMediaFilter)_filterGraph; try { // Add the video source int hr = _filterGraph.AddSourceFilter(file, "Ds.NET FileFilter", out capFilter); DsError.ThrowExceptionForHR(hr); // Get the SampleGrabber interface sampGrabber = new SampleGrabber() as ISampleGrabber; var baseGrabFlt = sampGrabber as IBaseFilter; ConfigureSampleGrabber(sampGrabber); // Add the frame grabber to the graph hr = _filterGraph.AddFilter(baseGrabFlt, "Ds.NET Grabber"); DsError.ThrowExceptionForHR(hr); // --------------------------------- // Connect the file filter to the sample grabber // Hopefully this will be the video pin, we could check by reading it's mediatype IPin iPinOut = DsFindPin.ByDirection(capFilter, PinDirection.Output, 0); // Get the input pin from the sample grabber IPin iPinIn = DsFindPin.ByDirection(baseGrabFlt, PinDirection.Input, 0); hr = _filterGraph.Connect(iPinOut, iPinIn); DsError.ThrowExceptionForHR(hr); // Add the null renderer to the graph nullrenderer = new NullRenderer() as IBaseFilter; hr = _filterGraph.AddFilter(nullrenderer, "Null renderer"); DsError.ThrowExceptionForHR(hr); // --------------------------------- // Connect the sample grabber to the null renderer iPinOut = DsFindPin.ByDirection(baseGrabFlt, PinDirection.Output, 0); iPinIn = DsFindPin.ByDirection(nullrenderer, PinDirection.Input, 0); hr = _filterGraph.Connect(iPinOut, iPinIn); DsError.ThrowExceptionForHR(hr); // Turn off the clock. This causes the frames to be sent // thru the graph as fast as possible hr = mediaFilt.SetSyncSource(null); DsError.ThrowExceptionForHR(hr); // Read and cache the image sizes SaveSizeInfo(sampGrabber); //Edit: get the duration hr = _mSeek.GetDuration(out _duration); DsError.ThrowExceptionForHR(hr); } finally { if (capFilter != null) { Marshal.ReleaseComObject(capFilter); } if (sampGrabber != null) { Marshal.ReleaseComObject(sampGrabber); } if (nullrenderer != null) { Marshal.ReleaseComObject(nullrenderer); } GC.Collect(); } } private void EstimateFrameCount() { try { //1sec / averageFrameTime double fr = 10000000.0 / _avgFrameTime; double frameCount = fr * (_duration / 10000000.0); OnFrameCountAvailable((long)frameCount); } catch { } } public double framesCounts() { double fr = 10000000.0 / _avgFrameTime; double frameCount = fr * (_duration / 10000000.0); return frameCount; } private void SaveSizeInfo(ISampleGrabber sampGrabber) { // Get the media type from the SampleGrabber var media = new AMMediaType(); int hr = sampGrabber.GetConnectedMediaType(media); DsError.ThrowExceptionForHR(hr); if ((media.formatType != FormatType.VideoInfo) || (media.formatPtr == IntPtr.Zero)) { throw new NotSupportedException("Unknown Grabber Media Format"); } // Grab the size info var videoInfoHeader = (VideoInfoHeader)Marshal.PtrToStructure(media.formatPtr, typeof(VideoInfoHeader)); _width = videoInfoHeader.BmiHeader.Width; _height = videoInfoHeader.BmiHeader.Height; //Edit: get framerate _avgFrameTime = videoInfoHeader.AvgTimePerFrame; DsUtils.FreeAMMediaType(media); GC.Collect(); } private void ConfigureSampleGrabber(ISampleGrabber sampGrabber) { var media = new AMMediaType { majorType = MediaType.Video, subType = MediaSubType.RGB24, formatType = FormatType.VideoInfo }; int hr = sampGrabber.SetMediaType(media); DsError.ThrowExceptionForHR(hr); DsUtils.FreeAMMediaType(media); GC.Collect(); hr = sampGrabber.SetCallback(this, 1); DsError.ThrowExceptionForHR(hr); } private void CloseInterfaces() { try { if (_mediaCtrl != null) { _mediaCtrl.Stop(); _mediaCtrl = null; dis = true; } } catch (Exception ex) { Debug.WriteLine(ex); } if (_filterGraph != null) { Marshal.ReleaseComObject(_filterGraph); _filterGraph = null; } GC.Collect(); } int ISampleGrabberCB.SampleCB(double sampleTime, IMediaSample pSample) { Marshal.ReleaseComObject(pSample); return 0; } int ISampleGrabberCB.BufferCB(double sampleTime, IntPtr pBuffer, int bufferLen) { if (Form1.ExtractAutomatic == true) { using (var bitmap = new Bitmap(_width, _height, _width * 3, PixelFormat.Format24bppRgb, pBuffer)) { if (!this.Secondpass) { long[] HistogramValues = Form1.GetHistogram(bitmap); long t = Form1.GetTopLumAmount(HistogramValues, 1000); Form1.averagesTest.Add(t); } else { //this is the changed part if (_frameId > 0) { if (Form1.averagesTest[_frameId] / 1000.0 - Form1.averagesTest[_frameId - 1] / 1000.0 > 150.0) { count = 6; } if (count > 0) { bitmap.RotateFlip(RotateFlipType.Rotate180FlipX); bitmap.Save(Path.Combine(_outFolder, _frameId.ToString("D6") + ".bmp")); count --; } } } _frameId++; //let only report each 100 frames for performance if (_frameId % 100 == 0) OnProgressChanged(_frameId); } } else { using (var bitmap = new Bitmap(_width, _height, _width * 3, PixelFormat.Format24bppRgb, pBuffer)) { if (!this.Secondpass) { //get avg double average = GetAveragePixelValue(bitmap); if (AveragesList == null) AveragesList = new List<double>(); //save avg AveragesList.Add(average); //***************************\\ // for (int i = 0; i < (int)framesCounts(); i++) // { // get histogram values long[] HistogramValues = Form1.GetHistogram(bitmap); if (histogramValuesList == null) histogramValuesList = new List<long>(256); histogramValuesList.AddRange(HistogramValues); //***************************\\ //} } else { if (FramesToSave != null && FramesToSave.Contains(_frameId)) { bitmap.RotateFlip(RotateFlipType.Rotate180FlipX); bitmap.Save(Path.Combine(_outFolder, _frameId.ToString("D6") + ".bmp")); // get histogram values long[] HistogramValues = Form1.GetHistogram(bitmap); if (histogramValuesList == null) histogramValuesList = new List<long>(256); histogramValuesList.AddRange(HistogramValues); using (BinaryWriter binWriter = new BinaryWriter(File.Open(fileName, FileMode.Create))) { for (int i = 0; i < histogramValuesList.Count; i++) { binWriter.Write(histogramValuesList[(int)i]); } binWriter.Close(); } } } _frameId++; //let only report each 100 frames for performance if (_frameId % 100 == 0) OnProgressChanged(_frameId); } } return 0; } /* int ISampleGrabberCB.SampleCB(double sampleTime, IMediaSample pSample) { Marshal.ReleaseComObject(pSample); return 0; } int ISampleGrabberCB.BufferCB(double sampleTime, IntPtr pBuffer, int bufferLen) { using (var bitmap = new Bitmap(_width, _height, _width * 3, PixelFormat.Format24bppRgb, pBuffer)) { if (!this.Secondpass) { //get avg double average = GetAveragePixelValue(bitmap); if (AveragesList == null) AveragesList = new List<double>(); //save avg AveragesList.Add(average); //***************************\\ // for (int i = 0; i < (int)framesCounts(); i++) // { // get histogram values long[] HistogramValues = Form1.GetHistogram(bitmap); if (histogramValuesList == null) histogramValuesList = new List<long>(256); histogramValuesList.AddRange(HistogramValues); long t = Form1.GetTopLumAmount(HistogramValues, 1000); //***************************\\ Form1.averagesTest.Add(t); // to add this list to a text file or binary file and read the averages from the file when its is Secondpass !!!!! //} } else { if (FramesToSave != null && FramesToSave.Contains(_frameId)) { bitmap.RotateFlip(RotateFlipType.Rotate180FlipX); bitmap.Save(Path.Combine(_outFolder, _frameId.ToString("D6") + ".bmp")); // get histogram values long[] HistogramValues = Form1.GetHistogram(bitmap); if (histogramValuesList == null) histogramValuesList = new List<long>(256); histogramValuesList.AddRange(HistogramValues); using (BinaryWriter binWriter = new BinaryWriter(File.Open(fileName, FileMode.Create))) { for (int i = 0; i < histogramValuesList.Count; i++) { binWriter.Write(histogramValuesList[(int)i]); } binWriter.Close(); } } for (int x = 1; x < Form1.averagesTest.Count; x++) { double fff = Form1.averagesTest[x] / 1000.0 - Form1.averagesTest[x - 1] / 1000.0; if (Form1.averagesTest[x] / 1000.0 - Form1.averagesTest[x - 1] / 1000.0 > 180.0) { bitmap.RotateFlip(RotateFlipType.Rotate180FlipX); bitmap.Save(Path.Combine(_outFolder, _frameId.ToString("D6") + ".bmp")); _frameId++; } } } _frameId++; //let only report each 100 frames for performance if (_frameId % 100 == 0) OnProgressChanged(_frameId); } return 0; }*/ private unsafe double GetAveragePixelValue(Bitmap bmp) { BitmapData bmData = null; try { bmData = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb); int stride = bmData.Stride; IntPtr scan0 = bmData.Scan0; int w = bmData.Width; int h = bmData.Height; double sum = 0; long pixels = bmp.Width * bmp.Height; byte* p = (byte*)scan0.ToPointer(); for (int y = 0; y < h; y++) { p = (byte*)scan0.ToPointer(); p += y * stride; for (int x = 0; x < w; x++) { double i = ((double)p[0] + p[1] + p[2]) / 3.0; sum += i; p += 3; } //no offset incrementation needed when getting //the pointer at the start of each row } bmp.UnlockBits(bmData); double result = sum / (double)pixels; return result; } catch { try { bmp.UnlockBits(bmData); } catch { } } return -1; } } public class FrameCountEventArgs { public long FrameCount { get; set; } } public class ProgressEventArgs { public int FrameID { get; set; } } } I remember i had this codec problem/s before and i installed the codec/'s that were needed but in this case both quick time and windows media player can play the video files so why the application cant detect and find the codec/'s on my computer ? Gspot say that the codec is AVC1 but again wmp and quicktime play the video files no problems. The video files are from my digital camera !

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  • Null reading in stream images? Unable to start activity ComponentInfo

    - by lasmith
    I have reviewed a lot of similar questions regarding not being able to launch an activity but they don't seem to quite match my problem. I am working on a simple black jack game but its force quitting. I suspect there is a problem with loading up the card png images I have. Stepping through the debugger it crashes right while in the resetGame() function. I'm sure I am doing something dumb. My Logcat: 10-15 20:21:43.309: E/AndroidRuntime(2863): FATAL EXCEPTION: main 10-15 20:21:43.309: E/AndroidRuntime(2863): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.smith.blackjack/com.smith.blackjack.Main}: java.lang.NullPointerException 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.ActivityThread.access$600(ActivityThread.java:130) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.os.Handler.dispatchMessage(Handler.java:99) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.os.Looper.loop(Looper.java:137) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.ActivityThread.main(ActivityThread.java:4745) 10-15 20:21:43.309: E/AndroidRuntime(2863): at java.lang.reflect.Method.invokeNative(Native Method) 10-15 20:21:43.309: E/AndroidRuntime(2863): at java.lang.reflect.Method.invoke(Method.java:511) 10-15 20:21:43.309: E/AndroidRuntime(2863): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 10-15 20:21:43.309: E/AndroidRuntime(2863): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 10-15 20:21:43.309: E/AndroidRuntime(2863): at dalvik.system.NativeStart.main(Native Method) 10-15 20:21:43.309: E/AndroidRuntime(2863): Caused by: java.lang.NullPointerException 10-15 20:21:43.309: E/AndroidRuntime(2863): at com.smith.blackjack.DeckOfCards.<init>(DeckOfCards.java:17) 10-15 20:21:43.309: E/AndroidRuntime(2863): at com.smith.blackjack.Main.resetGame(Main.java:98) 10-15 20:21:43.309: E/AndroidRuntime(2863): at com.smith.blackjack.Main.onCreate(Main.java:67) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.Activity.performCreate(Activity.java:5008) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079) 10-15 20:21:43.309: E/AndroidRuntime(2863): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023) 10-15 20:21:43.309: E/AndroidRuntime(2863): ... 11 more My androidmanifest: <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.smith.blackjack" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="11" android:targetSdkVersion="15" /> <application android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name=".Main" android:label="@string/title_activity_main" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> Here is my Main.java package com.smith.blackjack; import android.os.Bundle; import android.app.Activity; import android.content.res.AssetManager; import android.graphics.drawable.Drawable; import java.io.IOException; import java.io.InputStream; import android.util.Log; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.ImageView; public class Main extends Activity { private ImageView dealerCard0; private ImageView dealerCard1; private ImageView dealerCard2; private ImageView dealerCard3; private ImageView playerCard0; private ImageView playerCard1; private ImageView playerCard2; private ImageView playerCard3; private ImageView imgResult; private Button btnDeal; private Button btnDraw; private Button btnHold; private DeckOfCards deckOfCards; private int[] dealerValues; private int dealerSum; private int dealerCardNumber; private int[] playerValues; private int playerSum; private int playerCardNumber; private InputStream dealerHiddenCard; private Card dealerCard; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); dealerCard0 = (ImageView) findViewById(R.id.dealerCard0); dealerCard1 = (ImageView) findViewById(R.id.dealerCard1); dealerCard2 = (ImageView) findViewById(R.id.dealerCard2); dealerCard3 = (ImageView) findViewById(R.id.dealerCard3); playerCard0 = (ImageView) findViewById(R.id.playerCard0); playerCard1 = (ImageView) findViewById(R.id.playerCard1); playerCard2 = (ImageView) findViewById(R.id.playerCard2); playerCard3 = (ImageView) findViewById(R.id.playerCard3); imgResult = (ImageView) findViewById(R.id.imgResult); btnDeal = (Button) findViewById(R.id.deal); btnDraw = (Button) findViewById(R.id.draw); btnHold = (Button) findViewById(R.id.hold); btnDeal.setOnClickListener(btnDealListener); btnDraw.setOnClickListener(btnDrawListener); btnHold.setOnClickListener(btnHoldListener); resetGame(); } private void resetGame(){ AssetManager assets = getAssets(); dealerValues = new int[4]; playerValues = new int[4]; dealerSum = 0; playerSum = 0; dealerCardNumber = 0; playerCardNumber = 0; for (int i = 0; i < 4; i++) { dealerValues[i] = 0; playerValues[i] = 0; } try { InputStream stream = assets.open("cardback.png"); // stream = assets.open("cardback.png"); Drawable cardImage = Drawable.createFromStream(stream, null); dealerCard0.setImageDrawable(cardImage); dealerCard1.setImageDrawable(cardImage); dealerCard2.setImageDrawable(cardImage); dealerCard3.setImageDrawable(cardImage); playerCard0.setImageDrawable(cardImage); playerCard1.setImageDrawable(cardImage); playerCard2.setImageDrawable(cardImage); playerCard3.setImageDrawable(cardImage); imgResult.setImageDrawable(cardImage); deckOfCards = new DeckOfCards(); deckOfCards.shuffle(); assets.close(); } catch (IOException e){ Log.e("Reset Game", "Error Loading", e); } } public OnClickListener btnDealListener = new OnClickListener() { // @Override public void onClick(View v) { try { AssetManager assets = getAssets(); InputStream stream; // first player card Card newCard; newCard = deckOfCards.dealCard(); playerValues[playerCardNumber] = newCard.faceValue; playerCardNumber++; stream = assets.open(newCard.File); Drawable cardImage = Drawable.createFromStream(stream, newCard.File); playerCard0.setImageDrawable(cardImage); assets.close(); // second player card newCard = deckOfCards.dealCard(); playerValues[playerCardNumber] = newCard.faceValue; playerCardNumber++; stream = assets.open(newCard.File); cardImage = Drawable.createFromStream(stream, newCard.File); playerCard1.setImageDrawable(cardImage); assets.close(); // first dealer card hidden newCard = deckOfCards.dealCard(); dealerCard = newCard; dealerValues[dealerCardNumber] = newCard.faceValue; dealerCardNumber++; dealerHiddenCard = assets.open(newCard.File); stream = assets.open("cardback.png"); cardImage = Drawable.createFromStream(stream, "cardback"); dealerCard0.setImageDrawable(cardImage); assets.close(); // second dealer card open newCard = deckOfCards.dealCard(); dealerValues[dealerCardNumber] = newCard.faceValue; dealerCardNumber++; stream = assets.open(newCard.File); cardImage = Drawable.createFromStream(stream, newCard.File); dealerCard1.setImageDrawable(cardImage); assets.close(); } catch (IOException e){ Log.e("Deal", "Error Loading", e); } }; }; public OnClickListener btnDrawListener = new OnClickListener() { // @Override public void onClick(View v) { try { AssetManager assets = getAssets(); InputStream stream; // get next player card Card newCard; newCard = deckOfCards.dealCard(); playerValues[playerCardNumber] = newCard.faceValue; playerCardNumber++; stream = assets.open(newCard.File); Drawable cardImage = Drawable.createFromStream(stream, newCard.File); switch (playerCardNumber){ case 3: playerCard2.setImageDrawable(cardImage); case 4: playerCard3.setImageDrawable(cardImage); } assets.close(); } catch (IOException e){ Log.e("Draw", "Error Loading", e); } }; }; public OnClickListener btnHoldListener = new OnClickListener() { // @Override public void onClick(View v) { Drawable cardImage; // evaluate player hand playerSum = evaluate(playerValues); if (playerSum > 21){ // player losses } // flip over the dealer hidden card cardImage = Drawable.createFromStream(dealerHiddenCard, dealerCard.File); Card newCard; InputStream stream; AssetManager assets = getAssets(); for (int i=2; i<4; i++){ dealerSum = evaluate(dealerValues); if (dealerSum < 16 ) { newCard = deckOfCards.dealCard(); dealerValues[dealerCardNumber] = newCard.faceValue; dealerCardNumber++; try { stream = assets.open(newCard.File); cardImage = Drawable.createFromStream(stream, newCard.File); switch (dealerCardNumber){ case 3: dealerCard2.setImageDrawable(cardImage); case 4: dealerCard3.setImageDrawable(cardImage); } assets.close(); } catch (IOException e){ Log.e("Draw", "Error Loading", e); } if (dealerSum < playerSum) { // player wins } if (dealerSum > playerSum){ // dealer wins } if (dealerSum == playerSum){ // it is a draw } } } }; }; public int evaluate (int[]values) { int sumCards = 0; for (int i = 0; i < 4; i++){ sumCards += values[i]; } if (sumCards > 21) { for (int i = 0; i < 4; i++){ if (values[i] == 11) { values[i] = 1; sumCards -= 10; continue; } } } return sumCards; } } My DeckOfCards class: package com.smith.blackjack; import java.util.Random; public class DeckOfCards { private Card [] deck; private int currentCard; private static final int NUMBER_OF_CARDS = 52; private static final Random randomNumbers = new Random(); public DeckOfCards () { deck = new Card[NUMBER_OF_CARDS]; currentCard = 0 ; for(int count = 0; count < deck.length; count++) { deck[count].faceValue = count + 1; } } public void shuffle () { currentCard = 0; for (int first = 0; first < deck.length; first ++){ int second = randomNumbers.nextInt(NUMBER_OF_CARDS); int temp = deck[first].faceValue; deck[first].faceValue=deck[second].faceValue; deck[second].faceValue = temp; } } public Card dealCard(){ Card temp = new Card(); temp.faceValue = 0; temp.File = ""; if(currentCard < deck.length) { temp.faceValue = deck[currentCard].faceValue / 4; int suit = deck[currentCard].faceValue % 4; String suitString = ""; switch (suit){ case 0: suitString = "c"; case 1: suitString = "d"; case 2: suitString = "h"; case 3: suitString = "s"; } Integer face = temp.faceValue / 4 ; String faceString = face.toString(); temp.File = faceString + suitString + ".png"; switch (temp.faceValue){ case 11: temp.faceValue = 10; case 12: temp.faceValue = 10; case 13: temp.faceValue = 10; } return temp; } else return temp; } }

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  • OpenGL 3.x Assimp trouble implementing phong shading (normals?)

    - by Defcronyke
    I'm having trouble getting phong shading to look right. I'm pretty sure there's something wrong with either my OpenGL calls, or the way I'm loading my normals, but I guess it could be something else since 3D graphics and Assimp are both still very new to me. When trying to load .obj/.mtl files, the problems I'm seeing are: The models seem to be lit too intensely (less phong-style and more completely washed out, too bright). Faces that are lit seem to be lit equally all over (with the exception of a specular highlight showing only when the light source position is moved to be practically right on top of the model) Because of problems 1 and 2, spheres look very wrong: picture of sphere And things with larger faces look (less-noticeably) wrong too: picture of cube I could be wrong, but to me this doesn't look like proper phong shading. Here's the code that I think might be relevant (I can post more if necessary): file: assimpRenderer.cpp #include "assimpRenderer.hpp" namespace def { assimpRenderer::assimpRenderer(std::string modelFilename, float modelScale) { initSFML(); initOpenGL(); if (assImport(modelFilename)) // if modelFile loaded successfully { initScene(); mainLoop(modelScale); shutdownScene(); } shutdownOpenGL(); shutdownSFML(); } assimpRenderer::~assimpRenderer() { } void assimpRenderer::initSFML() { windowWidth = 800; windowHeight = 600; settings.majorVersion = 3; settings.minorVersion = 3; app = NULL; shader = NULL; app = new sf::Window(sf::VideoMode(windowWidth,windowHeight,32), "OpenGL 3.x Window", sf::Style::Default, settings); app->setFramerateLimit(240); app->setActive(); return; } void assimpRenderer::shutdownSFML() { delete app; return; } void assimpRenderer::initOpenGL() { GLenum err = glewInit(); if (GLEW_OK != err) { /* Problem: glewInit failed, something is seriously wrong. */ std::cerr << "Error: " << glewGetErrorString(err) << std::endl; } // check the OpenGL context version that's currently in use int glVersion[2] = {-1, -1}; glGetIntegerv(GL_MAJOR_VERSION, &glVersion[0]); // get the OpenGL Major version glGetIntegerv(GL_MINOR_VERSION, &glVersion[1]); // get the OpenGL Minor version std::cout << "Using OpenGL Version: " << glVersion[0] << "." << glVersion[1] << std::endl; return; } void assimpRenderer::shutdownOpenGL() { return; } void assimpRenderer::initScene() { // allocate heap space for VAOs, VBOs, and IBOs vaoID = new GLuint[scene->mNumMeshes]; vboID = new GLuint[scene->mNumMeshes*2]; iboID = new GLuint[scene->mNumMeshes]; glClearColor(0.4f, 0.6f, 0.9f, 0.0f); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); glEnable(GL_CULL_FACE); shader = new Shader("shader.vert", "shader.frag"); projectionMatrix = glm::perspective(60.0f, (float)windowWidth / (float)windowHeight, 0.1f, 100.0f); rot = 0.0f; rotSpeed = 50.0f; faceIndex = 0; colorArrayA = NULL; colorArrayD = NULL; colorArrayS = NULL; normalArray = NULL; genVAOs(); return; } void assimpRenderer::shutdownScene() { delete [] iboID; delete [] vboID; delete [] vaoID; delete shader; } void assimpRenderer::renderScene(float modelScale) { sf::Time elapsedTime = clock.getElapsedTime(); clock.restart(); if (rot > 360.0f) rot = 0.0f; rot += rotSpeed * elapsedTime.asSeconds(); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT); viewMatrix = glm::translate(glm::mat4(1.0f), glm::vec3(0.0f, -3.0f, -10.0f)); // move back a bit modelMatrix = glm::scale(glm::mat4(1.0f), glm::vec3(modelScale)); // scale model modelMatrix = glm::rotate(modelMatrix, rot, glm::vec3(0, 1, 0)); //modelMatrix = glm::rotate(modelMatrix, 25.0f, glm::vec3(0, 1, 0)); glm::vec3 lightPosition( 0.0f, -100.0f, 0.0f ); float lightPositionArray[3]; lightPositionArray[0] = lightPosition[0]; lightPositionArray[1] = lightPosition[1]; lightPositionArray[2] = lightPosition[2]; shader->bind(); int projectionMatrixLocation = glGetUniformLocation(shader->id(), "projectionMatrix"); int viewMatrixLocation = glGetUniformLocation(shader->id(), "viewMatrix"); int modelMatrixLocation = glGetUniformLocation(shader->id(), "modelMatrix"); int ambientLocation = glGetUniformLocation(shader->id(), "ambientColor"); int diffuseLocation = glGetUniformLocation(shader->id(), "diffuseColor"); int specularLocation = glGetUniformLocation(shader->id(), "specularColor"); int lightPositionLocation = glGetUniformLocation(shader->id(), "lightPosition"); int normalMatrixLocation = glGetUniformLocation(shader->id(), "normalMatrix"); glUniformMatrix4fv(projectionMatrixLocation, 1, GL_FALSE, &projectionMatrix[0][0]); glUniformMatrix4fv(viewMatrixLocation, 1, GL_FALSE, &viewMatrix[0][0]); glUniformMatrix4fv(modelMatrixLocation, 1, GL_FALSE, &modelMatrix[0][0]); glUniform3fv(lightPositionLocation, 1, lightPositionArray); for (unsigned int i = 0; i < scene->mNumMeshes; i++) { colorArrayA = new float[3]; colorArrayD = new float[3]; colorArrayS = new float[3]; material = scene->mMaterials[scene->mNumMaterials-1]; normalArray = new float[scene->mMeshes[i]->mNumVertices * 3]; unsigned int normalIndex = 0; for (unsigned int j = 0; j < scene->mMeshes[i]->mNumVertices * 3; j+=3, normalIndex++) { normalArray[j] = scene->mMeshes[i]->mNormals[normalIndex].x; // x normalArray[j+1] = scene->mMeshes[i]->mNormals[normalIndex].y; // y normalArray[j+2] = scene->mMeshes[i]->mNormals[normalIndex].z; // z } normalIndex = 0; glUniformMatrix3fv(normalMatrixLocation, 1, GL_FALSE, normalArray); aiColor3D ambient(0.0f, 0.0f, 0.0f); material->Get(AI_MATKEY_COLOR_AMBIENT, ambient); aiColor3D diffuse(0.0f, 0.0f, 0.0f); material->Get(AI_MATKEY_COLOR_DIFFUSE, diffuse); aiColor3D specular(0.0f, 0.0f, 0.0f); material->Get(AI_MATKEY_COLOR_SPECULAR, specular); colorArrayA[0] = ambient.r; colorArrayA[1] = ambient.g; colorArrayA[2] = ambient.b; colorArrayD[0] = diffuse.r; colorArrayD[1] = diffuse.g; colorArrayD[2] = diffuse.b; colorArrayS[0] = specular.r; colorArrayS[1] = specular.g; colorArrayS[2] = specular.b; // bind color for each mesh glUniform3fv(ambientLocation, 1, colorArrayA); glUniform3fv(diffuseLocation, 1, colorArrayD); glUniform3fv(specularLocation, 1, colorArrayS); // render all meshes glBindVertexArray(vaoID[i]); // bind our VAO glDrawElements(GL_TRIANGLES, scene->mMeshes[i]->mNumFaces*3, GL_UNSIGNED_INT, 0); glBindVertexArray(0); // unbind our VAO delete [] normalArray; delete [] colorArrayA; delete [] colorArrayD; delete [] colorArrayS; } shader->unbind(); app->display(); return; } void assimpRenderer::handleEvents() { sf::Event event; while (app->pollEvent(event)) { if (event.type == sf::Event::Closed) { app->close(); } if ((event.type == sf::Event::KeyPressed) && (event.key.code == sf::Keyboard::Escape)) { app->close(); } if (event.type == sf::Event::Resized) { glViewport(0, 0, event.size.width, event.size.height); } } return; } void assimpRenderer::mainLoop(float modelScale) { while (app->isOpen()) { renderScene(modelScale); handleEvents(); } } bool assimpRenderer::assImport(const std::string& pFile) { // read the file with some example postprocessing scene = importer.ReadFile(pFile, aiProcess_CalcTangentSpace | aiProcess_Triangulate | aiProcess_JoinIdenticalVertices | aiProcess_SortByPType); // if the import failed, report it if (!scene) { std::cerr << "Error: " << importer.GetErrorString() << std::endl; return false; } return true; } void assimpRenderer::genVAOs() { int vboIndex = 0; for (unsigned int i = 0; i < scene->mNumMeshes; i++, vboIndex+=2) { mesh = scene->mMeshes[i]; indexArray = new unsigned int[mesh->mNumFaces * sizeof(unsigned int) * 3]; // convert assimp faces format to array faceIndex = 0; for (unsigned int t = 0; t < mesh->mNumFaces; ++t) { const struct aiFace* face = &mesh->mFaces[t]; std::memcpy(&indexArray[faceIndex], face->mIndices, sizeof(float) * 3); faceIndex += 3; } // generate VAO glGenVertexArrays(1, &vaoID[i]); glBindVertexArray(vaoID[i]); // generate IBO for faces glGenBuffers(1, &iboID[i]); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, iboID[i]); glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(GLuint) * mesh->mNumFaces * 3, indexArray, GL_STATIC_DRAW); // generate VBO for vertices if (mesh->HasPositions()) { glGenBuffers(1, &vboID[vboIndex]); glBindBuffer(GL_ARRAY_BUFFER, vboID[vboIndex]); glBufferData(GL_ARRAY_BUFFER, mesh->mNumVertices * sizeof(GLfloat) * 3, mesh->mVertices, GL_STATIC_DRAW); glEnableVertexAttribArray((GLuint)0); glVertexAttribPointer((GLuint)0, 3, GL_FLOAT, GL_FALSE, 0, 0); } // generate VBO for normals if (mesh->HasNormals()) { normalArray = new float[scene->mMeshes[i]->mNumVertices * 3]; unsigned int normalIndex = 0; for (unsigned int j = 0; j < scene->mMeshes[i]->mNumVertices * 3; j+=3, normalIndex++) { normalArray[j] = scene->mMeshes[i]->mNormals[normalIndex].x; // x normalArray[j+1] = scene->mMeshes[i]->mNormals[normalIndex].y; // y normalArray[j+2] = scene->mMeshes[i]->mNormals[normalIndex].z; // z } normalIndex = 0; glGenBuffers(1, &vboID[vboIndex+1]); glBindBuffer(GL_ARRAY_BUFFER, vboID[vboIndex+1]); glBufferData(GL_ARRAY_BUFFER, mesh->mNumVertices * sizeof(GLfloat) * 3, normalArray, GL_STATIC_DRAW); glEnableVertexAttribArray((GLuint)1); glVertexAttribPointer((GLuint)1, 3, GL_FLOAT, GL_FALSE, 0, 0); delete [] normalArray; } // tex coord stuff goes here // unbind buffers glBindVertexArray(0); glBindBuffer(GL_ARRAY_BUFFER, 0); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0); delete [] indexArray; } vboIndex = 0; return; } } file: shader.vert #version 150 core in vec3 in_Position; in vec3 in_Normal; uniform mat4 projectionMatrix; uniform mat4 viewMatrix; uniform mat4 modelMatrix; uniform vec3 lightPosition; uniform mat3 normalMatrix; smooth out vec3 vVaryingNormal; smooth out vec3 vVaryingLightDir; void main() { // derive MVP and MV matrices mat4 modelViewProjectionMatrix = projectionMatrix * viewMatrix * modelMatrix; mat4 modelViewMatrix = viewMatrix * modelMatrix; // get surface normal in eye coordinates vVaryingNormal = normalMatrix * in_Normal; // get vertex position in eye coordinates vec4 vPosition4 = modelViewMatrix * vec4(in_Position, 1.0); vec3 vPosition3 = vPosition4.xyz / vPosition4.w; // get vector to light source vVaryingLightDir = normalize(lightPosition - vPosition3); // Set the position of the current vertex gl_Position = modelViewProjectionMatrix * vec4(in_Position, 1.0); } file: shader.frag #version 150 core out vec4 out_Color; uniform vec3 ambientColor; uniform vec3 diffuseColor; uniform vec3 specularColor; smooth in vec3 vVaryingNormal; smooth in vec3 vVaryingLightDir; void main() { // dot product gives us diffuse intensity float diff = max(0.0, dot(normalize(vVaryingNormal), normalize(vVaryingLightDir))); // multiply intensity by diffuse color, force alpha to 1.0 out_Color = vec4(diff * diffuseColor, 1.0); // add in ambient light out_Color += vec4(ambientColor, 1.0); // specular light vec3 vReflection = normalize(reflect(-normalize(vVaryingLightDir), normalize(vVaryingNormal))); float spec = max(0.0, dot(normalize(vVaryingNormal), vReflection)); if (diff != 0) { float fSpec = pow(spec, 128.0); // Set the output color of our current pixel out_Color.rgb += vec3(fSpec, fSpec, fSpec); } } I know it's a lot to look through, but I'm putting most of the code up so as not to assume where the problem is. Thanks in advance to anyone who has some time to help me pinpoint the problem(s)! I've been trying to sort it out for two days now and I'm not getting anywhere on my own.

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  • Reading data in from file

    - by user667430
    Hi Here is link if you want to download application: Simple banking app Text file with data to read I am trying to create a simple banking application that reads in data from a text file. So far i have managed to read in all the customers which there are 20 of them. However when reading in the accounts and transactions stuff it only reads in 20 but there is alot more in the text file. Here is what i have so far. I think it has something to do with the nested for loop in the getNextCustomer method. using System; using System.Collections; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.IO; using System.Linq; using System.Text; using System.Windows.Forms; namespace e_SOFT_Banking { public partial class Form1 : Form { public static ArrayList bankDetails = new ArrayList(); public static ArrayList accDetails = new ArrayList(); public static ArrayList tranDetails = new ArrayList(); string inputDataFile = @"C:\e-SOFT_v1.txt"; const int numCustItems = 14; const int numAccItems = 7; const int numTransItems = 5; public Form1() { InitializeComponent(); setUpBank(); } private void btnShowData_Click_1(object sender, EventArgs e) { showListsOfCust(); } private void setUpBank() { readData(); } private void showListsOfCust() { listBox1.Items.Clear(); foreach (Customer c in bankDetails) listBox1.Items.Add(c.getCustomerNumber() + " " + c.getCustomerTitle() + " " + c.getFirstName() + " " + c.getInitials() + " " + c.getSurname() + " " + c.getDateOfBirth() + " " + c.getHouseNameNumber() + " " + c.getStreetName() + " " + c.getArea() + " " + c.getCityTown() + " " + c.getCounty() + " " + c.getPostcode() + " " + c.getPassword() + " " + c.getNumberAccounts()); foreach (Account a in accDetails) listBox1.Items.Add(a.getAccSort() + " " + a.getAccNumber() + " " + a.getAccNick() + " " + a.getAccDate() + " " + a.getAccCurBal() + " " + a.getAccOverDraft() + " " + a.getAccNumTrans()); foreach (Transaction t in tranDetails) listBox1.Items.Add(t.getDate() + " " + t.getType() + " " + t.getDescription() + " " + t.getAmount() + " " + t.getBalAfter()); } private void readData() { StreamReader readerIn = null; Transaction curTrans; Account curAcc; Customer curCust; bool anyMoreData; string[] customerData = new string[numCustItems]; string[] accountData = new string[numAccItems]; string[] transactionData = new string[numTransItems]; if (readOK(inputDataFile, ref readerIn)) { anyMoreData = getNextCustomer(readerIn, customerData, accountData, transactionData); while (anyMoreData == true) { curCust = new Customer(customerData[0], customerData[1], customerData[2], customerData[3], customerData[4], customerData[5], customerData[6], customerData[7], customerData[8], customerData[9], customerData[10], customerData[11], customerData[12], customerData[13]); curAcc = new Account(accountData[0], accountData[1], accountData[2], accountData[3], accountData[4], accountData[5], accountData[6]); curTrans = new Transaction(transactionData[0], transactionData[1], transactionData[2], transactionData[3], transactionData[4]); bankDetails.Add(curCust); accDetails.Add(curAcc); tranDetails.Add(curTrans); anyMoreData = getNextCustomer(readerIn, customerData, accountData, transactionData); } if (readerIn != null) readerIn.Close(); } } private bool getNextCustomer(StreamReader inNext, string[] nextCustomerData, string[] nextAccountData, string[] nextTransactionData) { string nextLine; int numCItems = nextCustomerData.Count(); int numAItems = nextAccountData.Count(); int numTItems = nextTransactionData.Count(); for (int i = 0; i < numCItems; i++) { nextLine = inNext.ReadLine(); if (nextLine != null) { nextCustomerData[i] = nextLine; if (i == 13) { int cItems = Convert.ToInt32(nextCustomerData[13]); for (int q = 0; q < cItems; q++) { for (int a = 0; a < numAItems; a++) { nextLine = inNext.ReadLine(); nextAccountData[a] = nextLine; if (a == 6) { int aItems = Convert.ToInt32(nextAccountData[6]); for (int w = 0; w < aItems; w++) { for (int t = 0; t < numTItems; t++) { nextLine = inNext.ReadLine(); nextTransactionData[t] = nextLine; } } } } } } } else return false; } return true; } private bool readOK(string readFile, ref StreamReader readerIn) { try { readerIn = new StreamReader(readFile); return true; } catch (FileNotFoundException notFound) { MessageBox.Show("ERROR Opening file (when reading data in)" + " - File could not be found.\n" + notFound.Message); return false; } catch (Exception e) { MessageBox.Show("ERROR Opening File (when reading data in)" + "- Operation failed.\n" + e.Message); return false; } } } } I also have three classes one for customers, one for accounts and one for transactions, which follow in that order. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace e_SOFT_Banking { class Customer { private string customerNumber; private string customerTitle; private string firstName; private string initials; //not required - defaults to null private string surname; private string dateOfBirth; private string houseNameNumber; private string streetName; private string area; //not required - defaults to null private string cityTown; private string county; private string postcode; private string password; private int numberAccounts; public Customer(string theCustomerNumber, string theCustomerTitle, string theFirstName, string theInitials, string theSurname, string theDateOfBirth, string theHouseNameNumber, string theStreetName, string theArea, string theCityTown, string theCounty, string thePostcode, string thePassword, string theNumberAccounts) { customerNumber = theCustomerNumber; customerTitle = theCustomerTitle; firstName = theFirstName; initials = theInitials; surname = theSurname; dateOfBirth = theDateOfBirth; houseNameNumber = theHouseNameNumber; streetName = theStreetName; area = theArea; cityTown = theCityTown; county = theCounty; postcode = thePostcode; password = thePassword; setNumberAccounts(theNumberAccounts); } public string getCustomerNumber() { return customerNumber; } public string getCustomerTitle() { return customerTitle; } public string getFirstName() { return firstName; } public string getInitials() { return initials; } public string getSurname() { return surname; } public string getDateOfBirth() { return dateOfBirth; } public string getHouseNameNumber() { return houseNameNumber; } public string getStreetName() { return streetName; } public string getArea() { return area; } public string getCityTown() { return cityTown; } public string getCounty() { return county; } public string getPostcode() { return postcode; } public string getPassword() { return password; } public int getNumberAccounts() { return numberAccounts; } public void setCustomerNumber(string inCustomerNumber) { customerNumber = inCustomerNumber; } public void setCustomerTitle(string inCustomerTitle) { customerTitle = inCustomerTitle; } public void setFirstName(string inFirstName) { firstName = inFirstName; } public void setInitials(string inInitials) { initials = inInitials; } public void setSurname(string inSurname) { surname = inSurname; } public void setDateOfBirth(string inDateOfBirth) { dateOfBirth = inDateOfBirth; } public void setHouseNameNumber(string inHouseNameNumber) { houseNameNumber = inHouseNameNumber; } public void setStreetName(string inStreetName) { streetName = inStreetName; } public void setArea(string inArea) { area = inArea; } public void setCityTown(string inCityTown) { cityTown = inCityTown; } public void setCounty(string inCounty) { county = inCounty; } public void setPostcode(string inPostcode) { postcode = inPostcode; } public void setPassword(string inPassword) { password = inPassword; } public void setNumberAccounts(string inNumberAccounts) { try { numberAccounts = Convert.ToInt32(inNumberAccounts); } catch (FormatException invalidInput) { System.Windows.Forms.MessageBox.Show("ERROR" + invalidInput.Message + "Please enter a valid number"); } } } } Accounts: using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace e_SOFT_Banking { class Account { private string accSort; private Int64 accNumber; private string accNick; private string accDate; //not required - defaults to null private double accCurBal; private double accOverDraft; private int accNumTrans; public Account(string theAccSort, string theAccNumber, string theAccNick, string theAccDate, string theAccCurBal, string theAccOverDraft, string theAccNumTrans) { accSort = theAccSort; setAccNumber(theAccNumber); accNick = theAccNick; accDate = theAccDate; setAccCurBal(theAccCurBal); setAccOverDraft(theAccOverDraft); setAccNumTrans(theAccNumTrans); } public string getAccSort() { return accSort; } public long getAccNumber() { return accNumber; } public string getAccNick() { return accNick; } public string getAccDate() { return accDate; } public double getAccCurBal() { return accCurBal; } public double getAccOverDraft() { return accOverDraft; } public int getAccNumTrans() { return accNumTrans; } public void setAccSort(string inAccSort) { accSort = inAccSort; } public void setAccNumber(string inAccNumber) { try { accNumber = Convert.ToInt64(inAccNumber); } catch (FormatException invalidInput) { System.Windows.Forms.MessageBox.Show("ERROR" + invalidInput.Message + "Please enter a valid number"); } } public void setAccNick(string inAccNick) { accNick = inAccNick; } public void setAccDate(string inAccDate) { accDate = inAccDate; } public void setAccCurBal(string inAccCurBal) { try { accCurBal = Convert.ToDouble(inAccCurBal); } catch (FormatException invalidInput) { System.Windows.Forms.MessageBox.Show("ERROR" + invalidInput.Message + "Please enter a valid number"); } } public void setAccOverDraft(string inAccOverDraft) { try { accOverDraft = Convert.ToDouble(inAccOverDraft); } catch (FormatException invalidInput) { System.Windows.Forms.MessageBox.Show("ERROR" + invalidInput.Message + "Please enter a valid number"); } } public void setAccNumTrans(string inAccNumTrans) { try { accNumTrans = Convert.ToInt32(inAccNumTrans); } catch (FormatException invalidInput) { System.Windows.Forms.MessageBox.Show("ERROR" + invalidInput.Message + "Please enter a valid number"); } } } } Transactions: using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace e_SOFT_Banking { class Transaction { private string date; private string type; private string description; private double amount; //not required - defaults to null private double balAfter; public Transaction(string theDate, string theType, string theDescription, string theAmount, string theBalAfter) { date = theDate; type = theType; description = theDescription; setAmount(theAmount); setBalAfter(theBalAfter); } public string getDate() { return date; } public string getType() { return type; } public string getDescription() { return description; } public double getAmount() { return amount; } public double getBalAfter() { return balAfter; } public void setDate(string inDate) { date = inDate; } public void setType(string inType) { type = inType; } public void setDescription(string inDescription) { description = inDescription; } public void setAmount(string inAmount) { try { amount = Convert.ToDouble(inAmount); } catch (FormatException invalidInput) { System.Windows.Forms.MessageBox.Show("ERROR" + invalidInput.Message + "Please enter a valid number"); } } public void setBalAfter(string inBalAfter) { try { balAfter = Convert.ToDouble(inBalAfter); } catch (FormatException invalidInput) { System.Windows.Forms.MessageBox.Show("ERROR" + invalidInput.Message + "Please enter a valid number"); } } } } Any help greatly appreciated.

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  • I can''t figure out how to use the comboBox to remove radiobuttons

    - by user3576336
    import java.awt.EventQueue; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.border.EmptyBorder; import javax.swing.ButtonGroup; import javax.swing.JLabel; import javax.swing.JDesktopPane; import javax.swing.JRadioButton; import javax.swing.JComboBox; import java.awt.GridBagLayout; import java.awt.GridBagConstraints; import java.awt.Insets; import java.awt.Color; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; @SuppressWarnings("serial") public class Calendar1 extends JFrame implements ActionListener { private JPanel contentPane; String[] Months = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" }; JDesktopPane desktopPane; ButtonGroup bG = new ButtonGroup(); JRadioButton radioButton, rdbtnNewRadioButton, radioButton_1, radioButton_2, radioButton_3, radioButton_4, radioButton_5, radioButton_6, radioButton_7, radioButton_8, radioButton_9, radioButton_10, radioButton_11, radioButton_12, radioButton_13, radioButton_14, radioButton_15, radioButton_16, radioButton_17, radioButton_18, radioButton_19, radioButton_20, radioButton_21, radioButton_22, radioButton_23, radioButton_24, radioButton_25, radioButton_26, radioButton_27, radioButton_28, radioButton_29; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { Calendar1 frame = new Calendar1(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ @SuppressWarnings("unchecked") public Calendar1() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 521, 300); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(null); JComboBox comboBox = new JComboBox(Months); comboBox.setBounds(28, 16, 132, 27); contentPane.add(comboBox); comboBox.setSelectedIndex(0); comboBox.addActionListener(this); JLabel label = new JLabel("2014"); label.setBounds(350, 20, 61, 16); contentPane.add(label); desktopPane = new JDesktopPane(); desktopPane.setBackground(new Color(30, 144, 255)); desktopPane.setBounds(0, 63, 495, 188); contentPane.add(desktopPane); GridBagLayout gbl_desktopPane = new GridBagLayout(); gbl_desktopPane.columnWidths = new int[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; gbl_desktopPane.rowHeights = new int[] { 0, 0, 0, 0, 0, 0, 0, 0 }; gbl_desktopPane.columnWeights = new double[] { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, Double.MIN_VALUE }; gbl_desktopPane.rowWeights = new double[] { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, Double.MIN_VALUE }; desktopPane.setLayout(gbl_desktopPane); // JLabel lblSun = new JLabel("Sun"); // lblSun.setForeground(Color.RED); // // GridBagConstraints gbc_lblSun = new GridBagConstraints(); // gbc_lblSun.insets = new Insets(0, 0, 5, 5); // gbc_lblSun.gridx = 2; // gbc_lblSun.gridy = 0; // desktopPane.add(lblSun, gbc_lblSun); // // JLabel lblMon = new JLabel("Mon"); // GridBagConstraints gbc_lblMon = new GridBagConstraints(); // gbc_lblMon.insets = new Insets(0, 0, 5, 5); // gbc_lblMon.gridx = 4; // gbc_lblMon.gridy = 0; // desktopPane.add(lblMon, gbc_lblMon); // // JLabel lblTues = new JLabel("Tues"); // GridBagConstraints gbc_lblTues = new GridBagConstraints(); // gbc_lblTues.insets = new Insets(0, 0, 5, 5); // gbc_lblTues.gridx = 6; // gbc_lblTues.gridy = 0; // desktopPane.add(lblTues, gbc_lblTues); // // JLabel lblWed = new JLabel("Wed"); // GridBagConstraints gbc_lblWed = new GridBagConstraints(); // gbc_lblWed.insets = new Insets(0, 0, 5, 5); // gbc_lblWed.gridx = 8; // gbc_lblWed.gridy = 0; // desktopPane.add(lblWed, gbc_lblWed); // // JLabel lblThurs = new JLabel("Thurs"); // GridBagConstraints gbc_lblThurs = new GridBagConstraints(); // gbc_lblThurs.insets = new Insets(0, 0, 5, 5); // gbc_lblThurs.gridx = 10; // gbc_lblThurs.gridy = 0; // desktopPane.add(lblThurs, gbc_lblThurs); // // JLabel lblFri = new JLabel("Friday"); // GridBagConstraints gbc_lblFri = new GridBagConstraints(); // gbc_lblFri.insets = new Insets(0, 0, 5, 5); // gbc_lblFri.gridx = 12; // gbc_lblFri.gridy = 0; // desktopPane.add(lblFri, gbc_lblFri); // // JLabel lblSat = new JLabel("Sat"); // lblSat.setForeground(Color.RED); // GridBagConstraints gbc_lblSat = new GridBagConstraints(); // gbc_lblSat.insets = new Insets(0, 0, 5, 5); // gbc_lblSat.gridx = 14; // gbc_lblSat.gridy = 0; // desktopPane.add(lblSat, gbc_lblSat); radioButton = new JRadioButton("1"); GridBagConstraints gbc_radioButton = new GridBagConstraints(); gbc_radioButton.insets = new Insets(0, 0, 5, 5); gbc_radioButton.gridx = 8; gbc_radioButton.gridy = 1; desktopPane.add(radioButton, gbc_radioButton); bG.add(radioButton); rdbtnNewRadioButton = new JRadioButton("2"); GridBagConstraints gbc_rdbtnNewRadioButton = new GridBagConstraints(); gbc_rdbtnNewRadioButton.insets = new Insets(0, 0, 5, 5); gbc_rdbtnNewRadioButton.gridx = 10; gbc_rdbtnNewRadioButton.gridy = 1; desktopPane.add(rdbtnNewRadioButton, gbc_rdbtnNewRadioButton); bG.add(rdbtnNewRadioButton); radioButton_1 = new JRadioButton("3"); GridBagConstraints gbc_radioButton_1 = new GridBagConstraints(); gbc_radioButton_1.insets = new Insets(0, 0, 5, 5); gbc_radioButton_1.gridx = 12; gbc_radioButton_1.gridy = 1; desktopPane.add(radioButton_1, gbc_radioButton_1); bG.add(radioButton_1); radioButton_2 = new JRadioButton("4"); GridBagConstraints gbc_radioButton_2 = new GridBagConstraints(); gbc_radioButton_2.insets = new Insets(0, 0, 5, 5); gbc_radioButton_2.gridx = 14; gbc_radioButton_2.gridy = 1; desktopPane.add(radioButton_2, gbc_radioButton_2); bG.add(radioButton_2); radioButton_3 = new JRadioButton("5"); GridBagConstraints gbc_radioButton_3 = new GridBagConstraints(); gbc_radioButton_3.insets = new Insets(0, 0, 5, 5); gbc_radioButton_3.gridx = 2; gbc_radioButton_3.gridy = 2; desktopPane.add(radioButton_3, gbc_radioButton_3); bG.add(radioButton_3); radioButton_4 = new JRadioButton("6"); GridBagConstraints gbc_radioButton_4 = new GridBagConstraints(); gbc_radioButton_4.insets = new Insets(0, 0, 5, 5); gbc_radioButton_4.gridx = 4; gbc_radioButton_4.gridy = 2; desktopPane.add(radioButton_4, gbc_radioButton_4); bG.add(radioButton_4); radioButton_5 = new JRadioButton("7"); GridBagConstraints gbc_radioButton_5 = new GridBagConstraints(); gbc_radioButton_5.insets = new Insets(0, 0, 5, 5); gbc_radioButton_5.gridx = 6; gbc_radioButton_5.gridy = 2; desktopPane.add(radioButton_5, gbc_radioButton_5); bG.add(radioButton_5); radioButton_6 = new JRadioButton("8"); GridBagConstraints gbc_radioButton_6 = new GridBagConstraints(); gbc_radioButton_6.insets = new Insets(0, 0, 5, 5); gbc_radioButton_6.gridx = 8; gbc_radioButton_6.gridy = 2; desktopPane.add(radioButton_6, gbc_radioButton_6); bG.add(radioButton_6); radioButton_7 = new JRadioButton("9"); GridBagConstraints gbc_radioButton_7 = new GridBagConstraints(); gbc_radioButton_7.insets = new Insets(0, 0, 5, 5); gbc_radioButton_7.gridx = 10; gbc_radioButton_7.gridy = 2; desktopPane.add(radioButton_7, gbc_radioButton_7); bG.add(radioButton_7); radioButton_8 = new JRadioButton("10"); GridBagConstraints gbc_radioButton_8 = new GridBagConstraints(); gbc_radioButton_8.insets = new Insets(0, 0, 5, 5); gbc_radioButton_8.gridx = 12; gbc_radioButton_8.gridy = 2; desktopPane.add(radioButton_8, gbc_radioButton_8); bG.add(radioButton_8); radioButton_9 = new JRadioButton("11"); GridBagConstraints gbc_radioButton_9 = new GridBagConstraints(); gbc_radioButton_9.insets = new Insets(0, 0, 5, 5); gbc_radioButton_9.gridx = 14; gbc_radioButton_9.gridy = 2; desktopPane.add(radioButton_9, gbc_radioButton_9); bG.add(radioButton_9); radioButton_10 = new JRadioButton("12"); GridBagConstraints gbc_radioButton_10 = new GridBagConstraints(); gbc_radioButton_10.insets = new Insets(0, 0, 5, 5); gbc_radioButton_10.gridx = 2; gbc_radioButton_10.gridy = 3; desktopPane.add(radioButton_10, gbc_radioButton_10); bG.add(radioButton_10); radioButton_11 = new JRadioButton("13"); GridBagConstraints gbc_radioButton_11 = new GridBagConstraints(); gbc_radioButton_11.insets = new Insets(0, 0, 5, 5); gbc_radioButton_11.gridx = 4; gbc_radioButton_11.gridy = 3; desktopPane.add(radioButton_11, gbc_radioButton_11); bG.add(radioButton_11); radioButton_12 = new JRadioButton("14"); GridBagConstraints gbc_radioButton_12 = new GridBagConstraints(); gbc_radioButton_12.insets = new Insets(0, 0, 5, 5); gbc_radioButton_12.gridx = 6; gbc_radioButton_12.gridy = 3; desktopPane.add(radioButton_12, gbc_radioButton_12); bG.add(radioButton_12); radioButton_13 = new JRadioButton("15"); GridBagConstraints gbc_radioButton_13 = new GridBagConstraints(); gbc_radioButton_13.insets = new Insets(0, 0, 5, 5); gbc_radioButton_13.gridx = 8; gbc_radioButton_13.gridy = 3; desktopPane.add(radioButton_13, gbc_radioButton_13); bG.add(radioButton_13); radioButton_14 = new JRadioButton("16"); GridBagConstraints gbc_radioButton_14 = new GridBagConstraints(); gbc_radioButton_14.insets = new Insets(0, 0, 5, 5); gbc_radioButton_14.gridx = 10; gbc_radioButton_14.gridy = 3; desktopPane.add(radioButton_14, gbc_radioButton_14); bG.add(radioButton_14); radioButton_15 = new JRadioButton("17"); GridBagConstraints gbc_radioButton_15 = new GridBagConstraints(); gbc_radioButton_15.insets = new Insets(0, 0, 5, 5); gbc_radioButton_15.gridx = 12; gbc_radioButton_15.gridy = 3; desktopPane.add(radioButton_15, gbc_radioButton_15); bG.add(radioButton_15); radioButton_16 = new JRadioButton("18"); GridBagConstraints gbc_radioButton_16 = new GridBagConstraints(); gbc_radioButton_16.insets = new Insets(0, 0, 5, 5); gbc_radioButton_16.gridx = 14; gbc_radioButton_16.gridy = 3; desktopPane.add(radioButton_16, gbc_radioButton_16); bG.add(radioButton_16); radioButton_17 = new JRadioButton("19"); GridBagConstraints gbc_radioButton_17 = new GridBagConstraints(); gbc_radioButton_17.insets = new Insets(0, 0, 5, 5); gbc_radioButton_17.gridx = 2; gbc_radioButton_17.gridy = 4; desktopPane.add(radioButton_17, gbc_radioButton_17); bG.add(radioButton_17); radioButton_18 = new JRadioButton("20"); GridBagConstraints gbc_radioButton_18 = new GridBagConstraints(); gbc_radioButton_18.insets = new Insets(0, 0, 5, 5); gbc_radioButton_18.gridx = 4; gbc_radioButton_18.gridy = 4; desktopPane.add(radioButton_18, gbc_radioButton_18); bG.add(radioButton_18); radioButton_19 = new JRadioButton("21"); GridBagConstraints gbc_radioButton_19 = new GridBagConstraints(); gbc_radioButton_19.insets = new Insets(0, 0, 5, 5); gbc_radioButton_19.gridx = 6; gbc_radioButton_19.gridy = 4; desktopPane.add(radioButton_19, gbc_radioButton_19); bG.add(radioButton_19); radioButton_20 = new JRadioButton("22"); GridBagConstraints gbc_radioButton_20 = new GridBagConstraints(); gbc_radioButton_20.insets = new Insets(0, 0, 5, 5); gbc_radioButton_20.gridx = 8; gbc_radioButton_20.gridy = 4; desktopPane.add(radioButton_20, gbc_radioButton_20); bG.add(radioButton_20); radioButton_21 = new JRadioButton("23"); GridBagConstraints gbc_radioButton_21 = new GridBagConstraints(); gbc_radioButton_21.insets = new Insets(0, 0, 5, 5); gbc_radioButton_21.gridx = 10; gbc_radioButton_21.gridy = 4; desktopPane.add(radioButton_21, gbc_radioButton_21); bG.add(radioButton_21); radioButton_22 = new JRadioButton("24"); GridBagConstraints gbc_radioButton_22 = new GridBagConstraints(); gbc_radioButton_22.insets = new Insets(0, 0, 5, 5); gbc_radioButton_22.gridx = 12; gbc_radioButton_22.gridy = 4; desktopPane.add(radioButton_22, gbc_radioButton_22); bG.add(radioButton_22); radioButton_23 = new JRadioButton("25"); GridBagConstraints gbc_radioButton_23 = new GridBagConstraints(); gbc_radioButton_23.insets = new Insets(0, 0, 5, 5); gbc_radioButton_23.gridx = 14; gbc_radioButton_23.gridy = 4; desktopPane.add(radioButton_23, gbc_radioButton_23); bG.add(radioButton_23); radioButton_24 = new JRadioButton("26"); GridBagConstraints gbc_radioButton_24 = new GridBagConstraints(); gbc_radioButton_24.insets = new Insets(0, 0, 5, 5); gbc_radioButton_24.gridx = 2; gbc_radioButton_24.gridy = 5; desktopPane.add(radioButton_24, gbc_radioButton_24); bG.add(radioButton_24); radioButton_25 = new JRadioButton("27"); GridBagConstraints gbc_radioButton_25 = new GridBagConstraints(); gbc_radioButton_25.insets = new Insets(0, 0, 5, 5); gbc_radioButton_25.gridx = 4; gbc_radioButton_25.gridy = 5; desktopPane.add(radioButton_25, gbc_radioButton_25); bG.add(radioButton_25); radioButton_26 = new JRadioButton("28"); GridBagConstraints gbc_radioButton_26 = new GridBagConstraints(); gbc_radioButton_26.insets = new Insets(0, 0, 5, 5); gbc_radioButton_26.gridx = 6; gbc_radioButton_26.gridy = 5; desktopPane.add(radioButton_26, gbc_radioButton_26); bG.add(radioButton_26); radioButton_27 = new JRadioButton("29"); GridBagConstraints gbc_radioButton_27 = new GridBagConstraints(); gbc_radioButton_27.insets = new Insets(0, 0, 5, 5); gbc_radioButton_27.gridx = 8; gbc_radioButton_27.gridy = 5; desktopPane.add(radioButton_27, gbc_radioButton_27); bG.add(radioButton_27); radioButton_28 = new JRadioButton("30"); GridBagConstraints gbc_radioButton_28 = new GridBagConstraints(); gbc_radioButton_28.insets = new Insets(0, 0, 5, 5); gbc_radioButton_28.gridx = 10; gbc_radioButton_28.gridy = 5; desktopPane.add(radioButton_28, gbc_radioButton_28); bG.add(radioButton_28); radioButton_29 = new JRadioButton("31"); GridBagConstraints gbc_radioButton_29 = new GridBagConstraints(); gbc_radioButton_29.insets = new Insets(0, 0, 5, 5); gbc_radioButton_29.gridx = 12; gbc_radioButton_29.gridy = 5; desktopPane.add(radioButton_29, gbc_radioButton_29); bG.add(radioButton_29); } @Override public void actionPerformed(ActionEvent e) { JComboBox cb = (JComboBox) e.getSource(); String months = (String) cb.getSelectedItem(); if (months.equals("February")) { desktopPane.remove(radioButton_28); desktopPane.revalidate(); } } } I'm trying to use the combobox to remove radiobuttons in the actionperformed, but when I run the program, nothing happens, nor can I enable new buttons in the actionperformed. Thank you so much in advance for helping me out.

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  • What are good design practices when working with Entity Framework

    - by AD
    This will apply mostly for an asp.net application where the data is not accessed via soa. Meaning that you get access to the objects loaded from the framework, not Transfer Objects, although some recommendation still apply. This is a community post, so please add to it as you see fit. Applies to: Entity Framework 1.0 shipped with Visual Studio 2008 sp1. Why pick EF in the first place? Considering it is a young technology with plenty of problems (see below), it may be a hard sell to get on the EF bandwagon for your project. However, it is the technology Microsoft is pushing (at the expense of Linq2Sql, which is a subset of EF). In addition, you may not be satisfied with NHibernate or other solutions out there. Whatever the reasons, there are people out there (including me) working with EF and life is not bad.make you think. EF and inheritance The first big subject is inheritance. EF does support mapping for inherited classes that are persisted in 2 ways: table per class and table the hierarchy. The modeling is easy and there are no programming issues with that part. (The following applies to table per class model as I don't have experience with table per hierarchy, which is, anyway, limited.) The real problem comes when you are trying to run queries that include one or many objects that are part of an inheritance tree: the generated sql is incredibly awful, takes a long time to get parsed by the EF and takes a long time to execute as well. This is a real show stopper. Enough that EF should probably not be used with inheritance or as little as possible. Here is an example of how bad it was. My EF model had ~30 classes, ~10 of which were part of an inheritance tree. On running a query to get one item from the Base class, something as simple as Base.Get(id), the generated SQL was over 50,000 characters. Then when you are trying to return some Associations, it degenerates even more, going as far as throwing SQL exceptions about not being able to query more than 256 tables at once. Ok, this is bad, EF concept is to allow you to create your object structure without (or with as little as possible) consideration on the actual database implementation of your table. It completely fails at this. So, recommendations? Avoid inheritance if you can, the performance will be so much better. Use it sparingly where you have to. In my opinion, this makes EF a glorified sql-generation tool for querying, but there are still advantages to using it. And ways to implement mechanism that are similar to inheritance. Bypassing inheritance with Interfaces First thing to know with trying to get some kind of inheritance going with EF is that you cannot assign a non-EF-modeled class a base class. Don't even try it, it will get overwritten by the modeler. So what to do? You can use interfaces to enforce that classes implement some functionality. For example here is a IEntity interface that allow you to define Associations between EF entities where you don't know at design time what the type of the entity would be. public enum EntityTypes{ Unknown = -1, Dog = 0, Cat } public interface IEntity { int EntityID { get; } string Name { get; } Type EntityType { get; } } public partial class Dog : IEntity { // implement EntityID and Name which could actually be fields // from your EF model Type EntityType{ get{ return EntityTypes.Dog; } } } Using this IEntity, you can then work with undefined associations in other classes // lets take a class that you defined in your model. // that class has a mapping to the columns: PetID, PetType public partial class Person { public IEntity GetPet() { return IEntityController.Get(PetID,PetType); } } which makes use of some extension functions: public class IEntityController { static public IEntity Get(int id, EntityTypes type) { switch (type) { case EntityTypes.Dog: return Dog.Get(id); case EntityTypes.Cat: return Cat.Get(id); default: throw new Exception("Invalid EntityType"); } } } Not as neat as having plain inheritance, particularly considering you have to store the PetType in an extra database field, but considering the performance gains, I would not look back. It also cannot model one-to-many, many-to-many relationship, but with creative uses of 'Union' it could be made to work. Finally, it creates the side effet of loading data in a property/function of the object, which you need to be careful about. Using a clear naming convention like GetXYZ() helps in that regards. Compiled Queries Entity Framework performance is not as good as direct database access with ADO (obviously) or Linq2SQL. There are ways to improve it however, one of which is compiling your queries. The performance of a compiled query is similar to Linq2Sql. What is a compiled query? It is simply a query for which you tell the framework to keep the parsed tree in memory so it doesn't need to be regenerated the next time you run it. So the next run, you will save the time it takes to parse the tree. Do not discount that as it is a very costly operation that gets even worse with more complex queries. There are 2 ways to compile a query: creating an ObjectQuery with EntitySQL and using CompiledQuery.Compile() function. (Note that by using an EntityDataSource in your page, you will in fact be using ObjectQuery with EntitySQL, so that gets compiled and cached). An aside here in case you don't know what EntitySQL is. It is a string-based way of writing queries against the EF. Here is an example: "select value dog from Entities.DogSet as dog where dog.ID = @ID". The syntax is pretty similar to SQL syntax. You can also do pretty complex object manipulation, which is well explained [here][1]. Ok, so here is how to do it using ObjectQuery< string query = "select value dog " + "from Entities.DogSet as dog " + "where dog.ID = @ID"; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>(query, EntityContext.Instance)); oQuery.Parameters.Add(new ObjectParameter("ID", id)); oQuery.EnablePlanCaching = true; return oQuery.FirstOrDefault(); The first time you run this query, the framework will generate the expression tree and keep it in memory. So the next time it gets executed, you will save on that costly step. In that example EnablePlanCaching = true, which is unnecessary since that is the default option. The other way to compile a query for later use is the CompiledQuery.Compile method. This uses a delegate: static readonly Func<Entities, int, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, Dog>((ctx, id) => ctx.DogSet.FirstOrDefault(it => it.ID == id)); or using linq static readonly Func<Entities, int, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, Dog>((ctx, id) => (from dog in ctx.DogSet where dog.ID == id select dog).FirstOrDefault()); to call the query: query_GetDog.Invoke( YourContext, id ); The advantage of CompiledQuery is that the syntax of your query is checked at compile time, where as EntitySQL is not. However, there are other consideration... Includes Lets say you want to have the data for the dog owner to be returned by the query to avoid making 2 calls to the database. Easy to do, right? EntitySQL string query = "select value dog " + "from Entities.DogSet as dog " + "where dog.ID = @ID"; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>(query, EntityContext.Instance)).Include("Owner"); oQuery.Parameters.Add(new ObjectParameter("ID", id)); oQuery.EnablePlanCaching = true; return oQuery.FirstOrDefault(); CompiledQuery static readonly Func<Entities, int, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, Dog>((ctx, id) => (from dog in ctx.DogSet.Include("Owner") where dog.ID == id select dog).FirstOrDefault()); Now, what if you want to have the Include parametrized? What I mean is that you want to have a single Get() function that is called from different pages that care about different relationships for the dog. One cares about the Owner, another about his FavoriteFood, another about his FavotireToy and so on. Basicly, you want to tell the query which associations to load. It is easy to do with EntitySQL public Dog Get(int id, string include) { string query = "select value dog " + "from Entities.DogSet as dog " + "where dog.ID = @ID"; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>(query, EntityContext.Instance)) .IncludeMany(include); oQuery.Parameters.Add(new ObjectParameter("ID", id)); oQuery.EnablePlanCaching = true; return oQuery.FirstOrDefault(); } The include simply uses the passed string. Easy enough. Note that it is possible to improve on the Include(string) function (that accepts only a single path) with an IncludeMany(string) that will let you pass a string of comma-separated associations to load. Look further in the extension section for this function. If we try to do it with CompiledQuery however, we run into numerous problems: The obvious static readonly Func<Entities, int, string, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, string, Dog>((ctx, id, include) => (from dog in ctx.DogSet.Include(include) where dog.ID == id select dog).FirstOrDefault()); will choke when called with: query_GetDog.Invoke( YourContext, id, "Owner,FavoriteFood" ); Because, as mentionned above, Include() only wants to see a single path in the string and here we are giving it 2: "Owner" and "FavoriteFood" (which is not to be confused with "Owner.FavoriteFood"!). Then, let's use IncludeMany(), which is an extension function static readonly Func<Entities, int, string, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, string, Dog>((ctx, id, include) => (from dog in ctx.DogSet.IncludeMany(include) where dog.ID == id select dog).FirstOrDefault()); Wrong again, this time it is because the EF cannot parse IncludeMany because it is not part of the functions that is recognizes: it is an extension. Ok, so you want to pass an arbitrary number of paths to your function and Includes() only takes a single one. What to do? You could decide that you will never ever need more than, say 20 Includes, and pass each separated strings in a struct to CompiledQuery. But now the query looks like this: from dog in ctx.DogSet.Include(include1).Include(include2).Include(include3) .Include(include4).Include(include5).Include(include6) .[...].Include(include19).Include(include20) where dog.ID == id select dog which is awful as well. Ok, then, but wait a minute. Can't we return an ObjectQuery< with CompiledQuery? Then set the includes on that? Well, that what I would have thought so as well: static readonly Func<Entities, int, ObjectQuery<Dog>> query_GetDog = CompiledQuery.Compile<Entities, int, string, ObjectQuery<Dog>>((ctx, id) => (ObjectQuery<Dog>)(from dog in ctx.DogSet where dog.ID == id select dog)); public Dog GetDog( int id, string include ) { ObjectQuery<Dog> oQuery = query_GetDog(id); oQuery = oQuery.IncludeMany(include); return oQuery.FirstOrDefault; } That should have worked, except that when you call IncludeMany (or Include, Where, OrderBy...) you invalidate the cached compiled query because it is an entirely new one now! So, the expression tree needs to be reparsed and you get that performance hit again. So what is the solution? You simply cannot use CompiledQueries with parametrized Includes. Use EntitySQL instead. This doesn't mean that there aren't uses for CompiledQueries. It is great for localized queries that will always be called in the same context. Ideally CompiledQuery should always be used because the syntax is checked at compile time, but due to limitation, that's not possible. An example of use would be: you may want to have a page that queries which two dogs have the same favorite food, which is a bit narrow for a BusinessLayer function, so you put it in your page and know exactly what type of includes are required. Passing more than 3 parameters to a CompiledQuery Func is limited to 5 parameters, of which the last one is the return type and the first one is your Entities object from the model. So that leaves you with 3 parameters. A pitance, but it can be improved on very easily. public struct MyParams { public string param1; public int param2; public DateTime param3; } static readonly Func<Entities, MyParams, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, MyParams, IEnumerable<Dog>>((ctx, myParams) => from dog in ctx.DogSet where dog.Age == myParams.param2 && dog.Name == myParams.param1 and dog.BirthDate > myParams.param3 select dog); public List<Dog> GetSomeDogs( int age, string Name, DateTime birthDate ) { MyParams myParams = new MyParams(); myParams.param1 = name; myParams.param2 = age; myParams.param3 = birthDate; return query_GetDog(YourContext,myParams).ToList(); } Return Types (this does not apply to EntitySQL queries as they aren't compiled at the same time during execution as the CompiledQuery method) Working with Linq, you usually don't force the execution of the query until the very last moment, in case some other functions downstream wants to change the query in some way: static readonly Func<Entities, int, string, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, int, string, IEnumerable<Dog>>((ctx, age, name) => from dog in ctx.DogSet where dog.Age == age && dog.Name == name select dog); public IEnumerable<Dog> GetSomeDogs( int age, string name ) { return query_GetDog(YourContext,age,name); } public void DataBindStuff() { IEnumerable<Dog> dogs = GetSomeDogs(4,"Bud"); // but I want the dogs ordered by BirthDate gridView.DataSource = dogs.OrderBy( it => it.BirthDate ); } What is going to happen here? By still playing with the original ObjectQuery (that is the actual return type of the Linq statement, which implements IEnumerable), it will invalidate the compiled query and be force to re-parse. So, the rule of thumb is to return a List< of objects instead. static readonly Func<Entities, int, string, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, int, string, IEnumerable<Dog>>((ctx, age, name) => from dog in ctx.DogSet where dog.Age == age && dog.Name == name select dog); public List<Dog> GetSomeDogs( int age, string name ) { return query_GetDog(YourContext,age,name).ToList(); //<== change here } public void DataBindStuff() { List<Dog> dogs = GetSomeDogs(4,"Bud"); // but I want the dogs ordered by BirthDate gridView.DataSource = dogs.OrderBy( it => it.BirthDate ); } When you call ToList(), the query gets executed as per the compiled query and then, later, the OrderBy is executed against the objects in memory. It may be a little bit slower, but I'm not even sure. One sure thing is that you have no worries about mis-handling the ObjectQuery and invalidating the compiled query plan. Once again, that is not a blanket statement. ToList() is a defensive programming trick, but if you have a valid reason not to use ToList(), go ahead. There are many cases in which you would want to refine the query before executing it. Performance What is the performance impact of compiling a query? It can actually be fairly large. A rule of thumb is that compiling and caching the query for reuse takes at least double the time of simply executing it without caching. For complex queries (read inherirante), I have seen upwards to 10 seconds. So, the first time a pre-compiled query gets called, you get a performance hit. After that first hit, performance is noticeably better than the same non-pre-compiled query. Practically the same as Linq2Sql When you load a page with pre-compiled queries the first time you will get a hit. It will load in maybe 5-15 seconds (obviously more than one pre-compiled queries will end up being called), while subsequent loads will take less than 300ms. Dramatic difference, and it is up to you to decide if it is ok for your first user to take a hit or you want a script to call your pages to force a compilation of the queries. Can this query be cached? { Dog dog = from dog in YourContext.DogSet where dog.ID == id select dog; } No, ad-hoc Linq queries are not cached and you will incur the cost of generating the tree every single time you call it. Parametrized Queries Most search capabilities involve heavily parametrized queries. There are even libraries available that will let you build a parametrized query out of lamba expressions. The problem is that you cannot use pre-compiled queries with those. One way around that is to map out all the possible criteria in the query and flag which one you want to use: public struct MyParams { public string name; public bool checkName; public int age; public bool checkAge; } static readonly Func<Entities, MyParams, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, MyParams, IEnumerable<Dog>>((ctx, myParams) => from dog in ctx.DogSet where (myParams.checkAge == true && dog.Age == myParams.age) && (myParams.checkName == true && dog.Name == myParams.name ) select dog); protected List<Dog> GetSomeDogs() { MyParams myParams = new MyParams(); myParams.name = "Bud"; myParams.checkName = true; myParams.age = 0; myParams.checkAge = false; return query_GetDog(YourContext,myParams).ToList(); } The advantage here is that you get all the benifits of a pre-compiled quert. The disadvantages are that you most likely will end up with a where clause that is pretty difficult to maintain, that you will incur a bigger penalty for pre-compiling the query and that each query you run is not as efficient as it could be (particularly with joins thrown in). Another way is to build an EntitySQL query piece by piece, like we all did with SQL. protected List<Dod> GetSomeDogs( string name, int age) { string query = "select value dog from Entities.DogSet where 1 = 1 "; if( !String.IsNullOrEmpty(name) ) query = query + " and dog.Name == @Name "; if( age > 0 ) query = query + " and dog.Age == @Age "; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>( query, YourContext ); if( !String.IsNullOrEmpty(name) ) oQuery.Parameters.Add( new ObjectParameter( "Name", name ) ); if( age > 0 ) oQuery.Parameters.Add( new ObjectParameter( "Age", age ) ); return oQuery.ToList(); } Here the problems are: - there is no syntax checking during compilation - each different combination of parameters generate a different query which will need to be pre-compiled when it is first run. In this case, there are only 4 different possible queries (no params, age-only, name-only and both params), but you can see that there can be way more with a normal world search. - Noone likes to concatenate strings! Another option is to query a large subset of the data and then narrow it down in memory. This is particularly useful if you are working with a definite subset of the data, like all the dogs in a city. You know there are a lot but you also know there aren't that many... so your CityDog search page can load all the dogs for the city in memory, which is a single pre-compiled query and then refine the results protected List<Dod> GetSomeDogs( string name, int age, string city) { string query = "select value dog from Entities.DogSet where dog.Owner.Address.City == @City "; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>( query, YourContext ); oQuery.Parameters.Add( new ObjectParameter( "City", city ) ); List<Dog> dogs = oQuery.ToList(); if( !String.IsNullOrEmpty(name) ) dogs = dogs.Where( it => it.Name == name ); if( age > 0 ) dogs = dogs.Where( it => it.Age == age ); return dogs; } It is particularly useful when you start displaying all the data then allow for filtering. Problems: - Could lead to serious data transfer if you are not careful about your subset. - You can only filter on the data that you returned. It means that if you don't return the Dog.Owner association, you will not be able to filter on the Dog.Owner.Name So what is the best solution? There isn't any. You need to pick the solution that works best for you and your problem: - Use lambda-based query building when you don't care about pre-compiling your queries. - Use fully-defined pre-compiled Linq query when your object structure is not too complex. - Use EntitySQL/string concatenation when the structure could be complex and when the possible number of different resulting queries are small (which means fewer pre-compilation hits). - Use in-memory filtering when you are working with a smallish subset of the data or when you had to fetch all of the data on the data at first anyway (if the performance is fine with all the data, then filtering in memory will not cause any time to be spent in the db). Singleton access The best way to deal with your context and entities accross all your pages is to use the singleton pattern: public sealed class YourContext { private const string instanceKey = "On3GoModelKey"; YourContext(){} public static YourEntities Instance { get { HttpContext context = HttpContext.Current; if( context == null ) return Nested.instance; if (context.Items[instanceKey] == null) { On3GoEntities entity = new On3GoEntities(); context.Items[instanceKey] = entity; } return (YourEntities)context.Items[instanceKey]; } } class Nested { // Explicit static constructor to tell C# compiler // not to mark type as beforefieldinit static Nested() { } internal static readonly YourEntities instance = new YourEntities(); } } NoTracking, is it worth it? When executing a query, you can tell the framework to track the objects it will return or not. What does it mean? With tracking enabled (the default option), the framework will track what is going on with the object (has it been modified? Created? Deleted?) and will also link objects together, when further queries are made from the database, which is what is of interest here. For example, lets assume that Dog with ID == 2 has an owner which ID == 10. Dog dog = (from dog in YourContext.DogSet where dog.ID == 2 select dog).FirstOrDefault(); //dog.OwnerReference.IsLoaded == false; Person owner = (from o in YourContext.PersonSet where o.ID == 10 select dog).FirstOrDefault(); //dog.OwnerReference.IsLoaded == true; If we were to do the same with no tracking, the result would be different. ObjectQuery<Dog> oDogQuery = (ObjectQuery<Dog>) (from dog in YourContext.DogSet where dog.ID == 2 select dog); oDogQuery.MergeOption = MergeOption.NoTracking; Dog dog = oDogQuery.FirstOrDefault(); //dog.OwnerReference.IsLoaded == false; ObjectQuery<Person> oPersonQuery = (ObjectQuery<Person>) (from o in YourContext.PersonSet where o.ID == 10 select o); oPersonQuery.MergeOption = MergeOption.NoTracking; Owner owner = oPersonQuery.FirstOrDefault(); //dog.OwnerReference.IsLoaded == false; Tracking is very useful and in a perfect world without performance issue, it would always be on. But in this world, there is a price for it, in terms of performance. So, should you use NoTracking to speed things up? It depends on what you are planning to use the data for. Is there any chance that the data your query with NoTracking can be used to make update/insert/delete in the database? If so, don't use NoTracking because associations are not tracked and will causes exceptions to be thrown. In a page where there are absolutly no updates to the database, you can use NoTracking. Mixing tracking and NoTracking is possible, but it requires you to be extra careful with updates/inserts/deletes. The problem is that if you mix then you risk having the framework trying to Attach() a NoTracking object to the context where another copy of the same object exist with tracking on. Basicly, what I am saying is that Dog dog1 = (from dog in YourContext.DogSet where dog.ID == 2).FirstOrDefault(); ObjectQuery<Dog> oDogQuery = (ObjectQuery<Dog>) (from dog in YourContext.DogSet where dog.ID == 2 select dog); oDogQuery.MergeOption = MergeOption.NoTracking; Dog dog2 = oDogQuery.FirstOrDefault(); dog1 and dog2 are 2 different objects, one tracked and one not. Using the detached object in an update/insert will force an Attach() that will say "Wait a minute, I do already have an object here with the same database key. Fail". And when you Attach() one object, all of its hierarchy gets attached as well, causing problems everywhere. Be extra careful. How much faster is it with NoTracking It depends on the queries. Some are much more succeptible to tracking than other. I don't have a fast an easy rule for it, but it helps. So I should use NoTracking everywhere then? Not exactly. There are some advantages to tracking object. The first one is that the object is cached, so subsequent call for that object will not hit the database. That cache is only valid for the lifetime of the YourEntities object, which, if you use the singleton code above, is the same as the page lifetime. One page request == one YourEntity object. So for multiple calls for the same object, it will load only once per page request. (Other caching mechanism could extend that). What happens when you are using NoTracking and try to load the same object multiple times? The database will be queried each time, so there is an impact there. How often do/should you call for the same object during a single page request? As little as possible of course, but it does happens. Also remember the piece above about having the associations connected automatically for your? You don't have that with NoTracking, so if you load your data in multiple batches, you will not have a link to between them: ObjectQuery<Dog> oDogQuery = (ObjectQuery<Dog>)(from dog in YourContext.DogSet select dog); oDogQuery.MergeOption = MergeOption.NoTracking; List<Dog> dogs = oDogQuery.ToList(); ObjectQuery<Person> oPersonQuery = (ObjectQuery<Person>)(from o in YourContext.PersonSet select o); oPersonQuery.MergeOption = MergeOption.NoTracking; List<Person> owners = oPersonQuery.ToList(); In this case, no dog will have its .Owner property set. Some things to keep in mind when you are trying to optimize the performance. No lazy loading, what am I to do? This can be seen as a blessing in disguise. Of course it is annoying to load everything manually. However, it decreases the number of calls to the db and forces you to think about when you should load data. The more you can load in one database call the better. That was always true, but it is enforced now with this 'feature' of EF. Of course, you can call if( !ObjectReference.IsLoaded ) ObjectReference.Load(); if you want to, but a better practice is to force the framework to load the objects you know you will need in one shot. This is where the discussion about parametrized Includes begins to make sense. Lets say you have you Dog object public class Dog { public Dog Get(int id) { return YourContext.DogSet.FirstOrDefault(it => it.ID == id ); } } This is the type of function you work with all the time. It gets called from all over the place and once you have that Dog object, you will do very different things to it in different functions. First, it should be pre-compiled, because you will call that very often. Second, each different pages will want to have access to a different subset of the Dog data. Some will want the Owner, some the FavoriteToy, etc. Of course, you could call Load() for each reference you need anytime you need one. But that will generate a call to the database each time. Bad idea. So instead, each page will ask for the data it wants to see when it first request for the Dog object: static public Dog Get(int id) { return GetDog(entity,"");} static public Dog Get(int id, string includePath) { string query = "select value o " + " from YourEntities.DogSet as o " +

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