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  • passing data from an activity to an listactivity or listview

    - by wicked14
    need help on passing data from an activity to an listactivity or listview for an android app. im having problems on passing data to a listview. what the app do is from addact class the user can input things to do and in the viewact class this will display the activies add by the user in listview public class addact extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.newact); Button btn1 = (Button)findViewById(R.id.btnsave); final EditText et1 = (EditText)findViewById(R.id.etactivity); btn1.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { Intent it = new Intent(addact.this, viewact.class); it.putExtra("thekey", et1.getText().toString()); startActivity(it); } }); } } public class viewact extends ListActivity { String addToDo =getIntent().getExtras().getString("thekey"); String[] toDoAct = new String[] {addToDo }; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.viewact); setListAdapter(new ArrayAdapter<String>(this, R.layout.viewact,toDoAct)); ListView listView = getListView(); listView.setTextFilterEnabled(true); listView.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { for (int i=0; i < 2; i++) { Toast.makeText(getApplicationContext(), ((TextView) view).getText(), Toast.LENGTH_LONG).show(); } } }); } }

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  • BlackBerry 5.0 causing full menu to show on navigationClick

    - by jwadsack
    I have a BlackBerry app that is built for 4.5.x SDK. The first page of the app shows a list of fields and each field can be highlighted and clicked. The click action shows a new view with additional information about the field. This all works fine in 4.5, 4.6 and 4.7 and on the sim with 5.0. On a real 9000 running 5.0, when clicking the trackball on an item in the list, the full menu is showing rather than the click event getting consumed (or even fired) for the field. The view is derived from MainScreen and looks something like this: public class ListView extends MainScreen { public ItemCollection list = new ItemCollection; protected void sublayout( int maxWidth, int maxHeight ) { int i = 1; while(( item == (Item)list.nextElement()) != null) { ItemField field = new ItemField(item, i++); add(field); } } } This class does not consume navigationClick, but shouldn't need to, right? The field class does consume navigationClick event: public class ItemField extends Field { protected boolean navigationClick(int status, int time) { controller.showDeal(item.id, Session.current); return true; } } Is there something that changed in 5.0 that I need to add to have this app work the same for all platforms?

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  • Identifying a class which is extending an abstract class

    - by Simon A. Eugster
    Good Evening, I'm doing a major refactoring of http://wiki2xhtml.sourceforge.net/ to finally get better overview and maintainability. (I started the project when I decided to start programming, so – you get it, right? ;)) At the moment I wonder how to solve the problem I'll describe now: Every file will be put through several parsers (like one for links, one for tables, one for images, etc.): public class WikiLinks extends WikiTask { ... } public class WikiTables extends WikiTask { ... } The files will then be parsed about this way: public void parse() { if (!parse) return; WikiTask task = new WikiLinks(); do { task.parse(this); } while ((task = task.nextTask()) != null); } Sometimes I may want to use no parser at all (for files that only need to be copied), or only a chosen one (e.g. for testing purposes). So before running task.parse() I need to check whether this certain parser is actually necessary/desired. (Perhaps via Blacklist or Whitelist.) What would you suggest for comparing? An ID for each WikiTask (how to do?)? Comparing the task Object itself against a new instance of a WikiTask (overhead)?

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  • CodeIgniter -- unable to use an object

    - by Smandoli
    THE SUMMARY: When I call .../index.php/product, I receive: Fatal error: Call to a member function get_prod_single() on a non-object in /var/www/sparts/main/controllers/product.php on line 16 The offending Line 16 is: $data['pn_oem'] = $this->product_model->get_prod_single($product_id); Looks like I don't know how to make this a working object. Can you help me? THE CODE: In my /Models folder I have product_model.php: <?php class Product_model extends Model { function Product_model() { parent::Model(); } function get_prod_single($product_id) { //This will be a DB lookup ... return 'foo'; //stub to get going } } ?> In my /controllers folder I have product.php: <?php class Product extends Controller { function Product() { parent::Controller(); } function index() { $this->load->model('Product_model'); $product_id = 113; // will get this dynamically $data['product_id'] = $product_id; $data['pn_oem'] = $this->product_model->get_prod_single($product_id); $this->load->view('prod_single', $data); } } ?>

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  • Fill listview from fragment

    - by Bohsen
    I have a layout file containing a listview that I would like to fill with the help of a Fragment. But it continues to give me errors. The layout file: <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" > <ListView android:id="@+id/list" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_alignParentTop="true" > </ListView> <TableLayout android:id="@+id/details" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:stretchColumns="1" > <Button android:id="@+id/create_patient_button" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/create_patient_button" /> </TableLayout> </RelativeLayout> My fragmentActivity: public class BasicFragmentActivity extends FragmentActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.create_patient_view); FragmentManager fm = getSupportFragmentManager(); Fragment fragment = fm.findFragmentById(R.id.list); if (fragment == null) { FragmentTransaction ft = fm.beginTransaction(); ft.add(R.id.list, new BasicFragment()); ft.commit(); // Make sure you call commit or your Fragment will not be added. // This is very common mistake when working with Fragments! } } } My ListFragment: public class BasicFragment extends ListFragment { private PatientAdapter pAdapter; @Override public void onActivityCreated(Bundle savedState) { super.onActivityCreated(savedState); pAdapter = new PatientAdapter(getActivity(), GFRApplication.dPatients); setListAdapter(pAdapter); } } The error: java.lang.UnsupportedOperationException: addView(View) is not supported in AdapterView

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  • Android app crashes on Async Task

    - by Telmo Vaz
    why is my APP crashing when I invoke the AsyncTask? public class Login extends Activity { String mail; EditText mailIn; Button btSubmit; @Override protected void onCreate(Bundle tokenArg) { super.onCreate(tokenArg); setContentView(R.layout.login); mailIn = (EditText)findViewById(R.id.usermail); btSubmit = (Button)findViewById(R.id.submit); btSubmit.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View thisView) { new LoginProc().execute(); } }); } public class LoginProc extends AsyncTask<String, Void, Void> { @Override protected void onPreExecute() { mailIn = (EditText)findViewById(R.id.usermail); mail = mailIn.getText().toString(); super.onPreExecute(); } @Override protected Void doInBackground(String... params) { Toast.makeText(getApplicationContext(), mail, Toast.LENGTH_SHORT).show(); return null; } } } I'm trying to make the String name get it's value on the preExecute method, but it happens that the app crashes on that point. Even if I take the preExecute and do that on the doInBrackground, it still crashes. What's wrong?

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  • Ordering the results of a Hibernate Criteria query by using information of the child entities of the

    - by pkainulainen
    I have got two entities Person and Book. Only one instance of a specific book is stored to the system (When a book is added, application checks if that book is already found before adding a new row to the database). Relevant source code of the entities is can be found below: @Entity @Table(name="persons") @SequenceGenerator(name="id_sequence", sequenceName="hibernate_sequence") public class Person extends BaseModel { @Id @Column(name = "id") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "id_sequence") private Long id = null; @ManyToMany(targetEntity=Book.class) @JoinTable(name="persons_books", joinColumns = @JoinColumn( name="person_id"), inverseJoinColumns = @JoinColumn( name="book_id")) private List<Book> ownedBooks = new ArrayList<Book>(); } @Entity @Table(name="books") @SequenceGenerator(name="id_sequence", sequenceName="hibernate_sequence") public class Book extends BaseModel { @Id @Column(name = "id") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "id_sequence") private Long id = null; @Column(name="name") private String name = null; } My problem is that I want to find persons, which are owning some of the books owned by a specific persons. The returned list of persons should be ordered by using following logic: The person owning most of the same books should be at the first of the list, second person of the the list does not own as many books as the first person, but more than the third person. The code of the method performing this query is added below: @Override public List<Person> searchPersonsWithSimilarBooks(Long[] bookIds) { Criteria similarPersonCriteria = this.getSession().createCriteria(Person.class); similarPersonCriteria.add(Restrictions.in("ownedBooks.id", bookIds)); //How to set the ordering? similarPersonCriteria.addOrder(null); return similarPersonCriteria.list(); } My question is that can this be done by using Hibernate? And if so, how it can be done? I know I could implement a Comparator, but I would prefer using Hibernate to solve this problem.

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  • Calling a network State check from other activities

    - by Laurent
    I realize this question has been answered before but couldn't find an answer that deals with my specific case. I want to create a class called "InternetConnectionChecks" that will handle checking a network state and http timeouts. I'll call the methods twice in the app (once at the beginning to get data from a server, and once at the end to send user orders to the server). For good form I'd like to put all these methods in a single class rather than copy/paste at different points in my code. To check the network state, I'm using ConnectivityManager; thing is, getSystemService requires a class that extends Activity. package arbuckle.app; import android.app.Activity; import android.app.Service; import android.content.Context; import android.net.ConnectivityManager; import android.net.NetworkInfo; public class InternetConnectionChecks extends Activity { public boolean isNetworkAvailable(){ ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo(); if ((activeNetworkInfo != null)&&(activeNetworkInfo.isConnected())){ return true; }else{ return false; } } } QUESTION: if I call the method isNetworkAvailable from another activity, am I: - going to hit up serious errors. - violating good coding form? *If this isn't the right way to do things, can you point me in the right direction to set up a separate class I can call on to check internet connection? Thanks everyone!

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  • Need Help: adding MouseListeners to JComponents (Drawing a JComponent and then attaching a MouseListener)

    - by user1074574
    Drawing a JComponent and then attaching a MouseListener seems very simple to me, but not in this case: I'm having a problem with a MouseListener attached to a child JComponent; here's some brief code to help describe it: Note: The BGT class has implemented ActionListers/MouseListeners that do not have any code in them, and 'figures' is an array of SwingThings. public class GC extends BGT{ public GC(){ super(); buildJMenu(); drawPanel.addMouseListener(this); //drawPanel being the panel that draws the JComponents (it is a public variable in the BGT class) drawPanel.addMouseMotionListener(this); this.addMouseListener(this); } public static void main(String[] args){ GC a = new GC(); }... public void mouseClicked(MouseEvent e) { System.out.println(e.getSource()); //This only seems to print out the DrawPanel's information }... public void mouseReleased(MouseEvent e) { repaint(); ... tempMyJTextField = new MyJTextField(startX, startY, width, height); tempMyJTextField.addMouseListener(this); tempMyJTextField.addMouseMotionListener(this); figures.add(tempMyJTextField); for(int i = 0; i < figures.size(); i++) figures.get(i).addTo(drawPanel); } This is the addTo method in the MyJTextField class: public class MyJTextField extends JTextField implements SwingThing{ ... public void addTo(JPanel p) { p.add(myTextField); } ... } In the MouseClicked event it never registers that the JComponent was clicked. (The drawing/painting works fine) Thanks.

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  • Getting information from servlet created html

    - by user541597
    I have a servlet that creates an html text box and then redirects to another servlet on submit. How can I access the value of the html text box from the new servlet? I am able to access servlet variables from the new servlet but I am not aware of how to access the value of the html generated code. thanks, Here is the servlet that gets the text input public class ServletB extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { response.setContentType("text/html"); String value = System.getProperty("card"); PrintWriter out = response.getWriter(); out.println("<center><h1>Your preffered method of payment is "+value+"</h1><br />"); out.println("Please Enter Card Number<input type =\"text\" name = \"number\"/><form action=\"http://codd.cs.gsu.edu:9999/cpereyra183/servlet/ServletC\"><input type =\"submit\" value=\"Continue\" /><input type=\"button\" value=\"Cancel\" /></center>"); } }} This is the servlet the first servlet redirects to all I do is try to do is output the text input public class ServletC extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { response.setContentType("text/html"); String value = System.getProperty("card"); PrintWriter out = response.getWriter(); out.println(request.getParameter("number")); } }

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  • java template design

    - by Sean Nguyen
    Hi, I have this class: public class Converter { private Logger logger = Logger.getLogger(Converter.class); public String convert(String s){ if (s == null) throw new IllegalArgumentException("input can't be null"); logger.debug("Input = " + s); String r = s + "abc"; logger.debug("Output = " + s); return r; } public Integer convert(Integer s){ if (s == null) throw new IllegalArgumentException("input can't be null"); logger.debug("Input = " + s); Integer r = s + 10; logger.debug("Output = " + s); return r; } } The above 2 methods are very similar so I want to create a template to do the similar things and delegate the actual work to the approriate class. But I also want to easily extends this frame work without changing the template. So for example: public class ConverterTemplate { private Logger logger = Logger.getLogger(Converter.class); public Object convert(Object s){ if (s == null) throw new IllegalArgumentException("input can't be null"); logger.debug("Input = " + s); Object r = doConverter(); logger.debug("Output = " + s); return r; } protected abstract Object doConverter(Object arg); } public class MyConverter extends ConverterTemplate { protected String doConverter(String str) { String r = str + "abc"; return r; } protected Integer doConverter(Integer arg) { Integer r = arg + 10; return r; } } But that doesn't work. Can anybody suggest me a better way to do that? I want to achieve 2 goals: 1. A template that is extensible and does all the similar work for me. 2. I ant to minimize the number of extended class. Thanks,

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  • Followed the official android documentations but still could not use SQLite in app

    - by user366539
    My DBHelper class public class DBHelper extends SQLiteOpenHelper { public DBHelper(Context context) { super(context,"SIMPLE_DB",null,1); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL("CREATE TABLE SIMPLE_TABLE ( " + "ID INTEGER PRIMARY KEY " + "DESC TEXT);"); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } } Activity class public class SimpleDatabase extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); DBHelper dbHelper = new DBHelper(this); SQLiteDatabase db = dbHelper.getReadableDatabase(); db.execSQL("INSERT INTO SIMPLE_TABLE VALUES (NULL, 'test');"); Cursor cursor = db.rawQuery("SELECT * FROM SIMPLE_TABLE", null); TextView text = (TextView)findViewById(R.id.textbox); text.setText(cursor.getString(0)); } } I figure it crashed (application has stopped unexpectedly!) at SQLiteDatabase db = ... because if I commented the code out from there to the end then it worked fine. But I have no idea whatsoever why it does that. Any help would be appreciated.

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  • Can't declare an abstract method private....

    - by Zombies
    I want to do this, yet I can't. Here is my scenario and rational. I have an abstract class for test cases that has an abstract method called test(). The test() method is to be defined by the subclass; it is to be implemented with logic for a certain application, such as CRMAppTestCase extends CompanyTestCase. I don't want the test() method to be invoked directly, I want the super class to call the test() method while the sub class can call a method which calls this (and does other work too, such as setting a current date-time right before the test is executed for example). Example code: public abstract class CompanyTestCase { //I wish this would compile, but it cannot be declared private private abstract void test(); public TestCaseResult performTest() { //do some work which must be done and should be invoked whenever //this method is called (it would be improper to expect the caller // to perform initialization) TestCaseResult result = new TestCaseResult(); result.setBeginTime(new Date()); long time = System.currentTimeMillis(); test(); //invoke test logic result.setDuration(System.currentTimeMillis() - time); return result; } } Then to extend this.... public class CRMAppTestCase extends CompanyTestCase { public void test() { //test logic here } } Then to call it.... TestCaseResult result = new CRMAppTestCase().performTest();

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  • What else I must do allow my method to handle any type of objects

    - by NewHelpNeeder
    So to allow any type object I must use generics in my code. I have rewrote this method to do so, but then when I create an object, for example Milk, it won't let me pass it to my method. Ether there's something wrong with my generic revision, or Milk object I created is not good. How should I pass my object correctly and add it to linked list? This is a method that causes error when I insert an item: public void insertFirst(T dd) // insert at front of list { Link newLink = new Link(dd); // make new link if( isEmpty() ) // if empty list, last = newLink; // newLink <-- last else first.previous = newLink; // newLink <-- old first newLink.next = first; // newLink --> old first first = newLink; // first --> newLink } This is my class I try to insert into linked list: class Milk { String brand; double size; double price; Milk(String a, double b, double c) { brand = a; size = b; price = c; } } This is test method to insert the data: public static void main(String[] args) { // make a new list DoublyLinkedList theList = new DoublyLinkedList(); // this causes: // The method insertFirst(Comparable) in the type DoublyLinkedList is not applicable for the arguments (Milk) theList.insertFirst(new Milk("brand", 1, 2)); // insert at front theList.displayForward(); // display list forward theList.displayBackward(); // display list backward } // end main() } // end class DoublyLinkedApp Declarations: class Link<T extends Comparable<T>> {} class DoublyLinkedList<T extends Comparable<T>> {}

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  • CakePHP 2.0: how to access properties of the parent object?

    - by PaulJ
    I just started learning CakePHP 2.0 a few days ago, and there's one thing that is leaving me stumped: say I have an User model and a Posts model: class User extends AppModel { public $name = "User"; public $hasMany=array( 'Post' => array( 'className' => 'Post', 'foreignKey' => 'author_id' ) ); } class Post extends AppModel { public $name = 'Post'; public $belongsTo = array( 'className' = 'User', 'foreignKey' = 'author_id', ); } (Where "author_id" is the foreign key in the posts table that references the Users table's primary key). And now, in the PostsController, I want to access the properties of the user that owns the current post (to show his display name, for example). What would be the proper syntax? I tried: $this->Post->User->find('first', array('conditions' => array('User.id' => "$usuario"))) But it didn't work (I guess it's because the User is the parent of the Post object, not its child). Or should CakePHP load everything automatically, once you've declared the $hasMany and $belongsTo relationships?

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  • Why onCreate() calling multiple times when i use Thread()?

    - by RajaReddy PolamReddy
    In my app i faced a problem with threads. i am using native code in my app. i try to load library and then calling native functions from the android code. 1. By using Threads() : PjsuaThread pjsuaThread = new PjsuaThread(); pjsuaThread.start(); thread code class PjsuaThread extends Thread { public void run() { if (pjsua_app.initApp() != 0) { // native function calling return; } else { } pjsua_app.startPjsua(ApjsuaActivity.CFG_FNAME); // native function calling finished = true; } When i use code like this, onCreate() function calling multiple times and able to load library and calling some functions properly, after some seconds onCreate calling again because of that it's crashing. 2. Using AsyncTask(): And also i used AsyncTask< for this requirement, it's crashing the application( crashing in lib code ). not able to open any functions class SipTask extends AsyncTask<Void, String, Void> { protected Void doInBackground(Void... args) { if (pjsua_app.initApp() != 0) { return null; } else { } pjsua_app.startPjsua(ApjsuaActivity.CFG_FNAME); finished = true; return null; } @Override protected void onPostExecute(Void result) { super.onPostExecute(result); Log.i(TAG, "On POst "); } } What is annoying is that in most cases it is not the missing library, it's tried to able to load the lib crashing in between. any one know the reason ?

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  • Wrapping a Flash/AS3 Sprite as a Flex MXML component

    - by John
    For my game, I am making the main game view as a plain Flash/AS3 class, something like: public class GameArena extends Sprite This is simply a big rectangle in which game objects are drawn, so no need for fancy UI and I want to keep the main game engine Flex-free so I can use Sprites rather than heavier Flex components. However for the entire game/app, I do still want to use Flex for GUI/layout. So I thought I could create a Flex class subclassing UIComponent, which has a GameView object as a child... now I can use this in MXML as a standard Flex component. e.g. public class ArenaView extends UIComponent { public var gameArena:GameArena; override protected function createChildren():void { super.createChildren(); if (!gameArena) { gameArena = new GameArena(); gameArena.width = 200; gameArena.height = 200; addChild(gameArena); } } } Then I have a simple line in my main App MXML like: <logic:Arena x="0" y="0" width="50%" height="100%" name="TestArenaPanel" /> But so far while my code compiles, the Flash class isn't getting rendered. Maybe it's something simple, but I wanted to ask if this is a reasonable approach, or there is something better? BTW: I've had the "should Flex be used" conversation many times. If you want to discuss that please do so in comments, but keep answers on topic.

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  • Foiled by path-dependent types

    - by Ladlestein
    I'm having trouble using, in one trait, a Parser returned from a method in another trait. The compiler complains of a type mismatch and it appears to me that the problem is due to the path-dependent class. I'm not sure how to get what I want. trait Outerparser extends RegexParsers { def inner: Innerparser def quoted[T](something: Parser[T]) = "\"" ~> something <~ "\"" def quotedNumber = quoted(inner.number) // Compile error def quotedLocalNumber = quoted(number) // Compiles just fine def number: Parser[Int] = ("""[1-9][0-9]*"""r) ^^ {str => str.toInt} } trait Innerparser extends RegexParsers { def number: Parser[Int] = ("""[1-9][0-9]*"""r) ^^ {str => str.toInt} } And the error: [error] /Path/to/MyParser.scala:6: type mismatch [error] found : minerals.Innerparser#Parser[Int] [error] required: Outerparser.this.Parser[?] [error] def quotedNumber = quoted(inner.number) I sort-of get the idea: each "something" method is defining a Parser type whose path is specific to the enclosing class (Outerparser or Innerparser). The "quoted" method of Outerparser expects an an instance of type Outerparser.this.Parser but is getting Innerparser#Parser. I like to be able to use quoted with a parser obtained from this class or some other class. How can I do that?

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  • Storing same type but still getting an ArrayStoreException

    - by Firefoxx Pwnass
    I have strange problem. I have three classes. Book ( abstract ), and two subclasses ( Fiction, Nonfiction). I have created array of Book references. That array can hold both subclasse's objects. I'have following code for Fiction class. public class Fiction extends Book{ public Fiction(String title) { super(title); setPrice(); } public void setPrice() { super.price = 24.99; } } And the "same" code for Nonfiction class public class Nonfiction extends Book{ public Nonfiction(String title) { super(title); setPrice(); } public void setPrice() { super.price = 37.99; } } And this is Main program. import javax.swing.JOptionPane; public class Main { public static void main(String[] args) { Book[] book = new Fiction[6]; for(int i = 0; i<book.length; i++) { if(i<4) { String title = JOptionPane.showInputDialog("Enter fiction book, no "+i); book[i] = new Fiction(title); } else { String title = JOptionPane.showInputDialog("Enter non fiction book, no "+i); book[i] = new Nonfiction(title); } } for(int x = 0; x<book.length; x++) { System.out.println("Book named "+book[x].getTitle()+" costs "+book[x].getPrice()); } } } For any reason i'm getting ArrayStoreException on this line.. book[i] = new Nonfiction(title); But same code works for Fiction class. I checked java documentation and it says that this exception is thrown when i'm trying to store different objects in array ( like String and Int ), but in this case they are all the same objects. Both classes are children of superclass, that means, they are of the same type. I'm confsued. A little help here please?

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  • Can I make a derived class inherit a derived member from its base class in Java?

    - by Eric
    I have code that looks like this: public class A { public void doStuff() { System.out.print("Stuff successfully done"); } } public class B extends A { public void doStuff() { System.out.print("Stuff successfully done, but in a different way"); } public void doMoreStuff() { System.out.print("More advanced stuff successully done"); } } public class AWrapper { public A member; public AWrapper(A member) { this.member = member; } public void doStuffWithMember() { a.doStuff(); } } public class BWrapper extends AWrapper { public B member; public BWrapper(B member) { super(member); //Pointer to member stored in two places: this.member = member; //Not great if one changes, but the other does not } public void doStuffWithMember() { member.doMoreStuff(); } } However, there is a problem with this code. I'm storing a reference to the member in two places, but if one changes and the other does not, there could be trouble. I know that in Java, an inherited method can narrow down its return type (and perhaps arguments, but I'm not certain) to a derived class. Is the same true of fields?

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  • Database Tutorial: The method open() is undefined for the type MainActivity.DBAdapter

    - by user2203633
    I am trying to do this database tutorial on SQLite Eclipse: https://www.youtube.com/watch?v=j-IV87qQ00M But I get a few errors at the end.. at db.ppen(); i get error: The method open() is undefined for the type MainActivity.DBAdapter and similar for insert record and close. MainActivity: package com.example.studentdatabase; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import android.app.Activity; import android.app.ListActivity; import android.content.Intent; import android.database.Cursor; import android.os.Bundle; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.Button; import android.widget.Toast; public class MainActivity extends Activity { /** Called when the activity is first created. */ //DBAdapter db = new DBAdapter(this); @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Button addBtn = (Button)findViewById(R.id.add); addBtn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Intent i = new Intent(MainActivity.this, addassignment.class); startActivity(i); } }); try { String destPath = "/data/data/" + getPackageName() + "/databases/AssignmentDB"; File f = new File(destPath); if (!f.exists()) { CopyDB( getBaseContext().getAssets().open("mydb"), new FileOutputStream(destPath)); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } DBAdapter db = new DBAdapter(); //---add an assignment--- db.open(); long id = db.insertRecord("Hello World", "2/18/2012", "DPR 224", "First Android Project"); id = db.insertRecord("Workbook Exercises", "3/1/2012", "MAT 100", "Do odd numbers"); db.close(); //---get all Records--- /* db.open(); Cursor c = db.getAllRecords(); if (c.moveToFirst()) { do { DisplayRecord(c); } while (c.moveToNext()); } db.close(); */ /* //---get a Record--- db.open(); Cursor c = db.getRecord(2); if (c.moveToFirst()) DisplayRecord(c); else Toast.makeText(this, "No Assignments found", Toast.LENGTH_LONG).show(); db.close(); */ //---update Record--- /* db.open(); if (db.updateRecord(1, "Hello Android", "2/19/2012", "DPR 224", "First Android Project")) Toast.makeText(this, "Update successful.", Toast.LENGTH_LONG).show(); else Toast.makeText(this, "Update failed.", Toast.LENGTH_LONG).show(); db.close(); */ /* //---delete a Record--- db.open(); if (db.deleteRecord(1)) Toast.makeText(this, "Delete successful.", Toast.LENGTH_LONG).show(); else Toast.makeText(this, "Delete failed.", Toast.LENGTH_LONG).show(); db.close(); */ } private class DBAdapter extends BaseAdapter { private LayoutInflater mInflater; //private ArrayList<> @Override public int getCount() { return 0; } @Override public Object getItem(int arg0) { return null; } @Override public long getItemId(int arg0) { return 0; } @Override public View getView(int arg0, View arg1, ViewGroup arg2) { return null; } } public void CopyDB(InputStream inputStream, OutputStream outputStream) throws IOException { //---copy 1K bytes at a time--- byte[] buffer = new byte[1024]; int length; while ((length = inputStream.read(buffer)) > 0) { outputStream.write(buffer, 0, length); } inputStream.close(); outputStream.close(); } public void DisplayRecord(Cursor c) { Toast.makeText(this, "id: " + c.getString(0) + "\n" + "Title: " + c.getString(1) + "\n" + "Due Date: " + c.getString(2), Toast.LENGTH_SHORT).show(); } public void addAssignment(View view) { Intent i = new Intent("com.pinchtapzoom.addassignment"); startActivity(i); Log.d("TAG", "Clicked"); } } DBAdapter code: package com.example.studentdatabase; public class DBAdapter { public static final String KEY_ROWID = "id"; public static final String KEY_TITLE = "title"; public static final String KEY_DUEDATE = "duedate"; public static final String KEY_COURSE = "course"; public static final String KEY_NOTES = "notes"; private static final String TAG = "DBAdapter"; private static final String DATABASE_NAME = "AssignmentsDB"; private static final String DATABASE_TABLE = "assignments"; private static final int DATABASE_VERSION = 2; private static final String DATABASE_CREATE = "create table if not exists assignments (id integer primary key autoincrement, " + "title VARCHAR not null, duedate date, course VARCHAR, notes VARCHAR );"; private final Context context; private DatabaseHelper DBHelper; private SQLiteDatabase db; public DBAdapter(Context ctx) { this.context = ctx; DBHelper = new DatabaseHelper(context); } private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { try { db.execSQL(DATABASE_CREATE); } catch (SQLException e) { e.printStackTrace(); } } @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 contacts"); onCreate(db); } } //---opens the database--- public DBAdapter open() throws SQLException { db = DBHelper.getWritableDatabase(); return this; } //---closes the database--- public void close() { DBHelper.close(); } //---insert a record into the database--- public long insertRecord(String title, String duedate, String course, String notes) { ContentValues initialValues = new ContentValues(); initialValues.put(KEY_TITLE, title); initialValues.put(KEY_DUEDATE, duedate); initialValues.put(KEY_COURSE, course); initialValues.put(KEY_NOTES, notes); return db.insert(DATABASE_TABLE, null, initialValues); } //---deletes a particular record--- public boolean deleteContact(long rowId) { return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0; } //---retrieves all the records--- public Cursor getAllRecords() { return db.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_TITLE, KEY_DUEDATE, KEY_COURSE, KEY_NOTES}, null, null, null, null, null); } //---retrieves a particular record--- public Cursor getRecord(long rowId) throws SQLException { Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] {KEY_ROWID, KEY_TITLE, KEY_DUEDATE, KEY_COURSE, KEY_NOTES}, KEY_ROWID + "=" + rowId, null, null, null, null, null); if (mCursor != null) { mCursor.moveToFirst(); } return mCursor; } //---updates a record--- public boolean updateRecord(long rowId, String title, String duedate, String course, String notes) { ContentValues args = new ContentValues(); args.put(KEY_TITLE, title); args.put(KEY_DUEDATE, duedate); args.put(KEY_COURSE, course); args.put(KEY_NOTES, notes); return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0; } } addassignment code: package com.example.studentdatabase; public class addassignment extends Activity { DBAdapter db = new DBAdapter(this); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.add); } public void addAssignment(View v) { Log.d("test", "adding"); //get data from form EditText nameTxt = (EditText)findViewById(R.id.editTitle); EditText dateTxt = (EditText)findViewById(R.id.editDuedate); EditText courseTxt = (EditText)findViewById(R.id.editCourse); EditText notesTxt = (EditText)findViewById(R.id.editNotes); db.open(); long id = db.insertRecord(nameTxt.getText().toString(), dateTxt.getText().toString(), courseTxt.getText().toString(), notesTxt.getText().toString()); db.close(); nameTxt.setText(""); dateTxt.setText(""); courseTxt.setText(""); notesTxt.setText(""); Toast.makeText(addassignment.this,"Assignment Added", Toast.LENGTH_LONG).show(); } public void viewAssignments(View v) { Intent i = new Intent(this, MainActivity.class); startActivity(i); } } What is wrong here? Thanks in advance.

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  • Why are some classes created on the fly and others aren't in CakePHP 1.2.7?

    - by JoseMarmolejos
    I have the following model classes: class User extends AppModel { var $name= 'User'; var $belongsTo=array('SellerType' => array('className' => 'SellerType'), 'State' => array('className' => 'State'), 'Country' => array('className' => 'Country'), 'AdvertMethod' => array('className' => 'AdvertMethod'), 'UserType' => array('className' => 'UserType')); var $hasMany = array('UserQuery' => array('className' => 'UserQuery'));} And: class UserQuery extends AppModel { var $name = 'UserQuery'; var $belongsTo = array('User', 'ResidenceType', 'HomeType');} Everything works fine with the user class and all its associations, but the UserQuery class is being completely ignored by the orm (table name user_queries and the generated queries do cast it as UserQuery. Another weird thing is that if I delete the code inside the User class I get an error, but if I do the same for the UserQuery class I get no errors. So my question is why does cakephp generate a class on the fly for the UserQuery and ignores my class, and why doesn't it generate a class on the fly for the User as well ?

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  • How to delete Drawn Line in java?

    - by Jeyjey
    Hello Folks, well this is my code: import javax.swing.; import javax.; import java.awt.; import java.awt.Color; import java.awt.Graphics.; import java.awt.event.*; import javax.swing.UIManager; public class SimpleGUI extends JFrame{ public SimpleGUI(){ this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE) ; } public void go(){ Drawpanel = new Mypanel(); JFrame frame = new JFrame("Chasing Line"); frame.getContentPane().add(BorderLayout.CENTER, Drawpanel); frame.setSize(300,300); frame.setVisible(true); Drawpanel.addMouseMotionListener(new java.awt.event.MouseMotionAdapter() { public void mouseMoved(java.awt.event.MouseEvent evt) { DrawpanelMouseMoved(evt); } }); } public void DrawpanelMouseMoved(java.awt.event.MouseEvent evt) { xpos=evt.getX(); ypos=evt.getY(); System.out.println("Coordinates : X :"+ xpos+"Y: "+ypos); Drawpanel.paintImage(xpos,ypos); } class Mypanel extends JPanel{ public void paintImage(int xpost,int ypost){ Graphics d = getGraphics(); d.setColor(Color.black); d.drawLine(xpost, 0, xpost, this.getHeight()); d.setColor(Color.red); d.drawLine(0, ypost, this.getWidth(),ypost); this.validate(); } } // end the inner class public static void main(String[] args){ try { UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel"); } catch(Exception e) { System.err.println("Look and feel not set"); } SimpleGUI win = new SimpleGUI(); win.go(); } Mypanel Drawpanel; private int xpos=0; private int ypos=0; } // close SimpleGUI class The problem is how can i delete the old lines?, i mea,make only the current x and y lines appear on the screen, make the intersection between both lines "follow" the mouse pointer. thanks for any reply.

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  • Extending the CI_DB_active_record class in codeigniter 2.0

    - by ctrane
    I am writing my first program with Codeigniter, and have run into a problem. I will start with a focused description of the problem and can broaden it if I need to: I need to write a multi-dimensional array to the DB and want to use the insert_batch function from the CI_DB_active_record class to do so. The problem is that I need to write empty values as NULL for some fields while other fields need to be empty strings. The current function wraps all values with single quotes, and I cannot find a way to write null values to the database for specified fields. I would also like to increase the number of records per batch. I see how to extend models, libraries, etc., but is there a way to extend the CI_DB_active_record class without modifying core classes? The minimal amount of core class modification to make this work that I have found is modifying the following lines in the DB.php file (changing the require_once file to the new file that extends the CI_DB_active_record class and changing the CI_DB_active_record class name to the new class name): require_once(BASEPATH.'database/DB_active_rec'.EXT); if ( ! class_exists('CI_DB')) { eval('class CI_DB extends CI_DB_active_record { }'); } Can I do better?

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  • codeigniter and JSON

    - by ole
    Hello all i having a problem that it only get 1 value in my database and its my title and i want to show content and username from the same table to. here is my JSON kode <script type="text/javascript"> $.getJSON( 'ajax/forumThreads', function(data) { alert(data[0].overskrift); alert(data[0].indhold); } ); </script> my controller <?php class ajax extends Controller { function forumThreads() { $this->load->model('ajax_model'); $data['forum_list'] = $this->ajax_model->forumList(); if ($data['forum_list'] !== false) { echo json_encode($data['forum_list']); } } } my model fle <?php class ajax_model extends Model { function forumList() { $this->db->select('overskrift', 'indhold', 'brugernavn', 'dato'); $this->db->order_by('id', 'desc'); $this->db->limit(5); $forum_list = $this->db->get('forum_traad'); if($forum_list->num_rows() > 0) { return $forum_list->result_array(); } else { return false; } } }

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