Search Results

Search found 26134 results on 1046 pages for 'coming out of void'.

Page 58/1046 | < Previous Page | 54 55 56 57 58 59 60 61 62 63 64 65  | Next Page >

• Help with bugs in a C code

  - by Yanki Twizzy

  This C code is giving me some unpredictable results. The program is meant to collect 6 nos and print out the max, position of the max no and the average. It's supposed to have only 3 functions - input, max_avr_pos and output for doing what the code is supposed to do but I am getting unpredictable results. Please what could be the problem #include <stdio.h> #include <stdlib.h> #include <conio.h> void input_vals(int arrnum[]); void max_ave_val(int arrnum1[],double *average,int *maxval,int *position); void print_output(double *average1,int *maxval1,int *position1); int main(void) { int arrnum[6],maxval2,position2; double average2; input_vals(arrnum); max_ave_val(arrnum,&average2,&maxval2,&position2); print_output(&average2,&maxval2,&position2); _getche(); return 0; } void input_vals(int arrnum[]) { int count; printf("\n Please enter six numbers\n"); for(count=0;count<6;count++) { scanf("%d",&arrnum[count]); } } void max_ave_val(int arrnum1[],double *average,int *maxval,int *position) { int total=0; int cnt,cnt1,cnt2,limit,maxval2,post; limit=6; /* finding the max value*/ for(cnt=0;cnt<limit-1;cnt++) for(cnt1=limit-1;cnt1>cnt;--cnt1) { if(arrnum1[cnt1-1]>arrnum1[cnt1]) { maxval2=arrnum1[cnt-1]; post=(cnt-1)+1; } else { maxval2=arrnum1[cnt1]; post=cnt1+1; } } *maxval=maxval2; *position=post; /* solving for total */ for(cnt2=0;cnt2<limit;cnt2++); { total=total+arrnum1[cnt2]; } *average=total/limit; } void print_output(double *average1,int *maxval1,int *position1) { printf("\n value of the highest of the numbers is %d\n",*maxval1); printf("\n the average of all the numbers is %g\n",*average1); printf("\n the postion of the highest number in the list is %d\n",*position1); }

  Read the article

• In Google Glass, Menu Items are not shown after XE 17.2 Update, any Solutions?

  - by Amalan Dhananjayan

  This worked when the Glass in on XE12, I have opened the solution after about 2 Months and now with XE17 the menu items are not shown when tapped on the Live card, instead the live card is disappearing. I have updated the GDK, I have changed the code to support the latest GDK sneak peek version 2 changes according to this (https://developers.google.com/glass/release-notes#xe12) This is the code public class MenuActivity extends Activity { private static final String TAG = MenuActivity.class.getSimpleName(); private VisionService.VisionBinder mVisionService; private ServiceConnection mConnection = new ServiceConnection() { @Override public void onServiceConnected(ComponentName name, IBinder service) { if (service instanceof VisionService.VisionBinder) { mVisionService = (VisionService.VisionBinder) service; openOptionsMenu(); } // No need to keep the service bound. unbindService(this); } @Override public void onServiceDisconnected(ComponentName name) { } }; private boolean mResumed; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); bindService(new Intent(this, VisionService.class), mConnection, 0); } @Override protected void onResume() { super.onResume(); mResumed = true; openOptionsMenu(); } @Override protected void onPause() { super.onPause(); mResumed = false; } @Override public void openOptionsMenu() { if (mResumed && mConnection != null) { super.openOptionsMenu(); } } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.menu, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { int id = item.getItemId(); if (id == R.id.action_send) { mVisionService.requestWorkOrderCard(); finish(); return true; } else if (id == R.id.action_refresh) { mVisionService.requestTopWorkOrders(); finish(); return true; } else if (id == R.id.action_finish) { stopService(new Intent(this, VisionService.class)); finish(); return true; } else { return super.onOptionsItemSelected(item); } } @Override public void onOptionsMenuClosed(Menu menu) { super.onOptionsMenuClosed(menu); } } It would be great if any body could help on this. Thank You

  Read the article

• Can an asynchronously fired event run synchronously on a form?

  - by cyclotis04

  [VS 2010 Beta with .Net Framework 3.5] I've written a C# component to asynchronously monitor a socket and raise events when data is received. I set the VB form to show message boxes when the event is raised. What I've noticed is that when the component raises the event synchronously, the message box blocks the component code and locks the form until the user closes the message. When it's raised asynchronously, it neither blocks the code, nor locks the form. What I want is a way to raise an event in such a way that it does not block the code, but is called on the same thread as the form (so that it locks the form until the user selects an option.) Can you help me out? Thanks. [Component] using System; using System.Threading; using System.ComponentModel; namespace mySpace { public delegate void SyncEventHandler(object sender, SyncEventArgs e); public delegate void AsyncEventHandler(object sender, AsyncEventArgs e); public class myClass { readonly object syncEventLock = new object(); readonly object asyncEventLock = new object(); SyncEventHandler syncEvent; AsyncEventHandler asyncEvent; private delegate void WorkerDelegate(string strParam, int intParam); public void DoWork(string strParam, int intParam) { OnSyncEvent(new SyncEventArgs()); AsyncOperation asyncOp = AsyncOperationManager.CreateOperation(null); WorkerDelegate delWorker = new WorkerDelegate(ClientWorker); IAsyncResult result = delWorker.BeginInvoke(strParam, intParam, null, null); } private void ClientWorker(string strParam, int intParam) { Thread.Sleep(2000); OnAsyncEvent(new AsyncEventArgs()); OnAsyncEvent(new AsyncEventArgs()); } public event SyncEventHandler SyncEvent { add { lock (syncEventLock) syncEvent += value; } remove { lock (syncEventLock) syncEvent -= value; } } public event AsyncEventHandler AsyncEvent { add { lock (asyncEventLock) asyncEvent += value; } remove { lock (asyncEventLock) asyncEvent -= value; } } protected void OnSyncEvent(SyncEventArgs e) { SyncEventHandler handler; lock (syncEventLock) handler = syncEvent; if (handler != null) handler(this, e, null, null); // Blocks and locks //if (handler != null) handler.BeginInvoke(this, e, null, null); // Neither blocks nor locks } protected void OnAsyncEvent(AsyncEventArgs e) { AsyncEventHandler handler; lock (asyncEventLock) handler = asyncEvent; //if (handler != null) handler(this, e, null, null); // Blocks and locks if (handler != null) handler.BeginInvoke(this, e, null, null); // Neither blocks nor locks } } } [Form] Imports mySpace Public Class Form1 Public WithEvents component As New mySpace.myClass() Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click component.DoWork("String", 1) End Sub Private Sub component_SyncEvent(ByVal sender As Object, ByVal e As pbxapi.SyncEventArgs) Handles component.SyncEvent MessageBox.Show("Synchronous event", "Raised:", MessageBoxButtons.OK) End Sub Private Sub component_AsyncEvent(ByVal sender As Object, ByVal e As pbxapi.AsyncEventArgs) Handles component.AsyncEvent MessageBox.Show("Asynchronous event", "Raised:", MessageBoxButtons.OK) End Sub End Class

  Read the article

• How do I make a rectangle move in an image?

  - by alicedimarco

  Basically I have an image loaded, and when I click a portion of the image, a rectangle (with no fill) shows up. If I click another part of the image again, that rectangle will show up once more. With each click, the same rectangle should appear. So far I have this code, now I don't know how to make the image appear. My image from my file directory. I have already made the code to get the image from my file directory. import java.awt.Color; import java.awt.Graphics; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; public class MP2 extends JPanel implements MouseListener{ JFrame frame; JPanel panel; int x = 0; int y = 0; String input; public MP2(){ } public static void main(String[] args){ JFrame frame = new JFrame(); MP2 panel = new MP2(); panel.addMouseListener(panel); frame.add(panel); frame.setSize(200,200); frame.setVisible(true); } public void mouseClicked(MouseEvent event) { // TODO Auto-generated method stub this.x = event.getX(); this.y = event.getY(); this.repaint(); input = JOptionPane.showInputDialog("Something pops out"); System.out.println(input); } public void mouseEntered(MouseEvent arg0) { // TODO Auto-generated method stub } public void mouseExited(MouseEvent arg0) { // TODO Auto-generated method stub } public void mousePressed(MouseEvent arg0) { // TODO Auto-generated method stub } public void mouseReleased(MouseEvent arg0) { // TODO Auto-generated method stub } public void paintComponent(Graphics g){ super.paintComponent(g); // this.setBackground(Color.white); *Sets the bg color of the panel g.setColor(new Color(255,0,0)); g.drawRect(x, y, 100, 100); } }

  Read the article

• Getting field of type bytea in helper table when using GenerationType.IDENTITY

  - by dtrunk

  I'm creating my db scheme using Hibernate. There's a Table called "tbl_articles" and another one called "tbl_categories". To have a n-n relationship a helper table ("tbl_articles_categories") is needed. Here are all necessary Entities: @Entity @Table( name = "tbl_articles" ) public class Article implements Serializable { private static final long serialVersionUID = 1L; @Id @Column( nullable = false ) @GeneratedValue( strategy = GenerationType.IDENTITY ) private Integer id; // other fields... public Integer getId() { return id; } public void setId( Integer id ) { this.id = id; } // other fields... } @Entity @Table( name = "tbl_categories" ) public class Category implements Serializable { private static final long serialVersionUID = 1L; @Id @Column( nullable = false ) @GeneratedValue( strategy = GenerationType.IDENTITY ) private Integer id; // other fields public Integer getId() { return id; } public void setId( Integer id ) { this.id = id; } // other fields... } @Entity @Table( name = "tbl_articles_categories" ) @AssociationOverrides({ @AssociationOverride( name = "pk.article", joinColumns = @JoinColumn( name = "article_id" ) ), @AssociationOverride( name = "pk.category", joinColumns = @JoinColumn( name = "category_id" ) ) }) public class ArticleCategory { private ArticleCategoryPK pk = new ArticleCategoryPK(); public void setPk( ArticleCategoryPK pk ) { this.pk = pk; } @EmbeddedId public ArticleCategoryPK getPk() { return pk; } @Transient public Article getArticle() { return pk.getArticle(); } public void setArticle( Article article ) { pk.setArticle( article ); } @Transient public Category getCategory() { return pk.getCategory(); } public void setCategory( Category category ) { pk.setCategory( category ); } } @Embeddable public class ArticleCategoryPK implements Serializable { private static final long serialVersionUID = 1L; @ManyToOne @ForeignKey( name = "tbl_articles_categories_fkey_article_id" ) private Article article; @ManyToOne @ForeignKey( name = "tbl_articles_categories_fkey_category_id" ) private Category category; public ArticleCategoryPK( Article article, Category category ) { setArticle( article ); setCategory( category ); } public ArticleCategoryPK() { } public Article getArticle() { return article; } public void setArticle( Article article ) { this.article = article; } public Category getCategory() { return category; } public void setCategory( Category category ) { this.category = category; } } Now, I'm getting a serial type what I wanted in my articles table as well as in my categories table. But looking into my helper table, there aren't the expected fields article_id and category_id each of type integer - instead there are article and category of type bytea. What's wrong here? EDIT: Sorry, forgot to mention that I'm using PostgreSQL.

  Read the article

• How to refresh a fragment in a viewpager?

  - by aut_silvia

  I know there are already some questions to this problem. But I am really new in Android and ecspecially to Fragments and Viewpager. Pls have passion with me. I didn't found a answer which fits to my code. I dont know how to refresh a fragment or reload it when it's "active" again. TabsPagerAdapter.java: public class TabsPagerAdapter extends FragmentPagerAdapter{ public TabsPagerAdapter(FragmentManager fm){ super(fm); } @Override public Fragment getItem(int index) { switch (index) { case 0: return new KFZFragment(); case 1: return new LogFragment(); case 2: return new TrackFragment(); } return null; } @Override public int getCount() { // get item count - equal to number of tabs return 3; } } I have this 3 Fragments (KFZFragment,LogFragment,TrackFragment) and on the TrackFragment I calculate some data and this data should be display in a ListView in LogFragment. But when I change to LogFragment it's not the latest data. So it doesnt refresh. Now how should I modify my code to refresh the fragments when it's "active"? MainActivityFragment.java: public class MainActivityFragment extends FragmentActivity implements ActionBar.TabListener{ private ViewPager viewPager; private TabsPagerAdapter mAdapter; private ActionBar actionBar; List<Fragment> fragments; private String[] tabs = { "KFZ", "Fahrten Log", "Kosten Track" }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main_fragment); // Initilization viewPager = (ViewPager) findViewById(R.id.pager); actionBar = getActionBar(); mAdapter = new TabsPagerAdapter(getSupportFragmentManager()); fragments = new Vector<Fragment>(); fragments.add(Fragment.instantiate(this, KFZFragment.class.getName(),savedInstanceState)); fragments.add(Fragment.instantiate(this, LogFragment.class.getName(),savedInstanceState)); viewPager.setAdapter(mAdapter); actionBar.setHomeButtonEnabled(false); actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS); // Adding Tabs for (String tab_name : tabs) { actionBar.addTab(actionBar.newTab().setText(tab_name) .setTabListener(this)); } viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() { @Override public void onPageSelected(int position) { // on changing the page // make respected tab selected actionBar.setSelectedNavigationItem(position); } @Override public void onPageScrolled(int arg0, float arg1, int arg2) { } @Override public void onPageScrollStateChanged(int arg0) { } }); } @Override public void onTabReselected(Tab tab, FragmentTransaction ft) { // TODO Auto-generated method stub } @Override public void onTabSelected(Tab tab, FragmentTransaction ft) { viewPager.setCurrentItem(tab.getPosition()); } @Override public void onTabUnselected(Tab tab, FragmentTransaction ft) { // TODO Auto-generated method stub } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_BACK) { } return super.onKeyDown(keyCode, event); } } Pls help me out.

  Read the article

• Download a file using cocoa

  - by dododedodonl

  Hi All, I want to download a file to the downloads folder. I searched google for this and found the NSURLDownload class. I've read the page in the dev center and created this code (with some copy and pasting) this code: @implementation Downloader @synthesize downloadResponse; - (void)startDownloadingURL:(NSString*)downloadUrl destenation:(NSString*)destenation { // create the request NSURLRequest *theRequest=[NSURLRequest requestWithURL:[NSURL URLWithString:downloadUrl] cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0]; // create the connection with the request // and start loading the data NSURLDownload *theDownload=[[NSURLDownload alloc] initWithRequest:theRequest delegate:self]; if (!theDownload) { NSLog(@"Download could not be made..."); } } - (void)download:(NSURLDownload *)download decideDestinationWithSuggestedFilename:(NSString *)filename { NSString *destinationFilename; NSString *homeDirectory=NSHomeDirectory(); destinationFilename=[[homeDirectory stringByAppendingPathComponent:@"Desktop"] stringByAppendingPathComponent:filename]; [download setDestination:destinationFilename allowOverwrite:NO]; } - (void)download:(NSURLDownload *)download didFailWithError:(NSError *)error { // release the connection [download release]; // inform the user NSLog(@"Download failed! Error - %@ %@", [error localizedDescription], [[error userInfo] objectForKey:NSErrorFailingURLStringKey]); } - (void)downloadDidFinish:(NSURLDownload *)download { // release the connection [download release]; // do something with the data NSLog(@"downloadDidFinish"); } - (void)setDownloadResponse:(NSURLResponse *)aDownloadResponse { [aDownloadResponse retain]; [downloadResponse release]; downloadResponse = aDownloadResponse; } - (void)download:(NSURLDownload *)download didReceiveResponse:(NSURLResponse *)response { // reset the progress, this might be called multiple times bytesReceived = 0; // retain the response to use later [self setDownloadResponse:response]; } - (void)download:(NSURLDownload *)download didReceiveDataOfLength:(unsigned)length { long long expectedLength = [[self downloadResponse] expectedContentLength]; bytesReceived = bytesReceived+length; if (expectedLength != NSURLResponseUnknownLength) { percentComplete = (bytesReceived/(float)expectedLength)*100.0; NSLog(@"Percent - %f",percentComplete); } else { NSLog(@"Bytes received - %d",bytesReceived); } } -(NSURLRequest *)download:(NSURLDownload *)download willSendRequest:(NSURLRequest *)request redirectResponse:(NSURLResponse *)redirectResponse { NSURLRequest *newRequest=request; if (redirectResponse) { newRequest=nil; } return newRequest; } @end But my problem is now, it doesn't appear on the desktop as specified. And I want to put it in downloads and not on the desktop... What do I have to do?

  Read the article

• Random generates same number in java

  - by user1613360

  This is my java code. import java.io.*; import java.util.*; import java.util.concurrent.TimeUnit; class search { private int numelem; private int[] input=new int[100]; public void setNumofelem() { System.out.println("Enter the total numebr of elements"); Scanner yz=new Scanner(System.in); numelem=yz.nextInt(); } public void randomnumber() throws Exception { int max=500,min=1,n=numelem; Random rand = new Random(); for (int j=0;j < n;j++) { input[j]=rand.nextInt(max)+1; } } public void printinput() { int b=numelem,t=0; while(true) if(b!=0) { System.out.print(" "+input[t]); b--; t++; } else break; } } public class mycode { public static void main(String args[]) throws Exception { search a=new search(); a.setNumofelem(); a.randomnumber(); a.printinput(); } } Now the function randomnumber() just returns the same number.The function executes perfectly if I execute it as a separate java program but fails miserably if I call it using an object.I have also tried the following variations but nothing works everything return the same number. Variation 1: public void randomnumber() throws Exception { int max=500,min=1,n=numelem; Random rand = new Random(); for (int j=0;j < n;j++) { TimeUnit.SECONDS.sleep(1); input[j]=rand.nextInt(max)+1; } } Variation 2: public void randomnumber() throws Exception { int max=500,min=1,n=numelem; Random rand = new Random(); for (int j=0;j < n;j++) { rand.setSeed(System.nanoTime()); input[j]=rand.nextInt(max)+1; } } Variation 3: public void randomnumber() throws Exception { int max=500,min=1,n=numelem; Random rand = new Random(); for (int j=0;j < n;j++) { TimeUnit.SECONDS.sleep(1); rand.setSeed(System.nanoTime()); input[j]=rand.nextInt(max)+1; } } Sample input/Output: Enter the number of elements: 5 23 23 23 23 23 23

  Read the article

• c++ multithread array

  - by user1731972

  i'm doing something for fun, trying to learn multithreading Problems passing array by reference to threads but Arno pointed out that my threading via process.h wasn't going to be multi-threaded. What I'm hoping to do is something where I have an array of 100 (or 10,000, doesn't really matter I don't think), and split up the assignment of values to each thread. Example, 4 threads = 250 values per thread to be assigned. Then I can use this filled array for further calculations. Here's some code I was working on (which doesn't work) #include <process.h> #include <windows.h> #include <iostream> #include <fstream> #include <time.h> //#include <thread> using namespace std; void myThread (void *dummy ); CRITICAL_SECTION cs1,cs2; // global int main() { ofstream myfile; myfile.open ("coinToss.csv"); int rNum; long numRuns; long count = 0; int divisor = 1; float holder = 0; int counter = 0; float percent = 0.0; HANDLE hThread[1000]; int array[10000]; srand ( time(NULL) ); printf ("Runs (use multiple of 10)? "); cin >> numRuns; for (int i = 0; i < numRuns; i++) { //_beginthread( myThread, 0, (void *) (array1) ); //??? //hThread[i * 2] = _beginthread( myThread, 0, (void *) (array1) ); hThread[i*2] = _beginthread( myThread, 0, (void *) (array) ); } //WaitForMultipleObjects(numRuns * 2, hThread, TRUE, INFINITE); WaitForMultipleObjects(numRuns, hThread, TRUE, INFINITE); } void myThread (void *param ) { //thanks goes to stockoverflow //http://stackoverflow.com/questions/12801862/problems-passing-array-by-reference-to-threads int *i = (int *)param; for (int x = 0; x < 1000000; x++) { //param[x] = rand() % 2 + 1; i[x] = rand() % 2 + 1; } } Can anyone explain why it isn't working?

  Read the article

• How to retreive Bundle Version in a label from project test-Info.plist in iphone?

  - by aman-gupta

  Hi, Here I m pasting my codes where i want to retrive Bundle version from my test-Info.plist. // // testAppDelegate.h // test // // Created by Fortune1 on 20/04/10. // Copyright __MyCompanyName__ 2010. All rights reserved. // #import <UIKit/UIKit.h> @class testViewController; @interface testAppDelegate : NSObject <UIApplicationDelegate> { UIWindow *window; testViewController *viewController; } @property (nonatomic, retain) IBOutlet UIWindow *window; @property (nonatomic, retain) IBOutlet testViewController *viewController; @end ////////////// // // testAppDelegate.m // test // // Created by Fortune1 on 20/04/10. // Copyright __MyCompanyName__ 2010. All rights reserved. // #import "testAppDelegate.h" #import "testViewController.h" @implementation testAppDelegate @synthesize window; @synthesize viewController; - (void)applicationDidFinishLaunching:(UIApplication *)application { // Override point for customization after app launch [window addSubview:viewController.view]; [window makeKeyAndVisible]; } - (void)dealloc { [viewController release]; [window release]; [super dealloc]; } @end ///////////////////// // // testViewController.h // test // // Created by Fortune1 on 20/04/10. // Copyright __MyCompanyName__ 2010. All rights reserved. // #import <UIKit/UIKit.h> @interface testViewController : UIViewController { UILabel *label; } @property(nonatomic,retain) IBOutlet UILabel *label; @end /////////////////////// // // testViewController.m // test // // Created by Fortune1 on 20/04/10. // Copyright __MyCompanyName__ 2010. All rights reserved. // #import "testViewController.h" @implementation testViewController @synthesize label; /* // The designated initializer. Override to perform setup that is required before the view is loaded. - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) { // Custom initialization } return self; } */ /* // Implement loadView to create a view hierarchy programmatically, without using a nib. - (void)loadView { } */ - (void)viewDidLoad { [super viewDidLoad]; NSString *path = [[NSBundle mainBundle] pathForResource:@"test-info" ofType:@"plist"]; NSString *versionString = [NSString stringWithFormat:@"v%d", [plistData objectForKey:@"Bundle version"]]; label.text = versionString; } /* // Override to allow orientations other than the default portrait orientation. - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { // Return YES for supported orientations return (interfaceOrientation == UIInterfaceOrientationPortrait); } */ - (void)didReceiveMemoryWarning { // Releases the view if it doesn't have a superview. [super didReceiveMemoryWarning]; // Release any cached data, images, etc that aren't in use. } - (void)viewDidUnload { // Release any retained subviews of the main view. // e.g. self.myOutlet = nil; } - (void)dealloc { [super dealloc]; } @end But still I got null value where i m wrong please help me out Thanks in advance

  Read the article

• makecontext segfault?

  - by cdietschrun

  I am working on a homework assignment that will be due in the next semester. It requires us to implement our own context switching/thread library using the ucontext API. The professor provides code that does it, but before a thread returns, he manually does some work and calls an ISR that finds another thread to use and swapcontexts to it or if none are left, exits. The point of the assignment is to use the uc_link field of the context so that when it hits a return it takes care of the work. I've created a function (type void/void args) that just does the work the functions did before (clean up and then calls ISR). The professor said he wanted this. So all that's left is to do a makecontext somewhere along the way on the context in the uc_link field so that it runs my thread, right? Well, when I do makecontext on seemingly any combination of ucontext_t's and function, I get a segfault and gdb provides no help.. I can skip the makecontext and my program exist 'normally' when it hits a return in the threads I created because (presumably) the uc_link field is not properly setup (which is what I'm trying to do). I also can't find anything on why makecontext would segfault. Can anyone help? stack2.ss_sp = (void *)(malloc(STACKSIZE)); if(stack2.ss_sp == NULL){ printf("thread failed to get stack space\n"); exit(8); } stack2.ss_size = STACKSIZE; stack2.ss_flags = 0; if(getcontext(&main_context) == -1){ perror("getcontext in t_init, rtn_env"); exit(5); } //main_context.uc_stack = t_state[i].mystk; main_context.uc_stack = stack2; main_context.uc_link = 0; makecontext(&main_context, (void (*)(void))thread_rtn, 0); I've also tried just thread_rtn, &thread_rtn and other things. thread_rtn is declared as void thread_rtn(void). later, in each thread. run_env is of type ucontext_t: ... t_state[i].run_env.uc_link = &main_context;

  Read the article

• C++ - Error: expected unqualified-id before ‘using’

  - by Francisco P.

  Hello, everyone. I am having some trouble on a project I'm working on. Here's the header file for the calor class: #ifndef _CALOR_ #define _CALOR_ #include "gradiente.h" using namespace std; class Calor : public Gradiente { public: Calor(); Calor(int a); ~Calor(); int getTemp(); int getMinTemp(); void setTemp(int a); void setMinTemp(int a); void mostraSensor(); }; #endif When I try to compile it: calor.h|6|error: expected unqualified-id before ‘using’| Why does this happen? I've been searching online and learned this error occurs mostly due to corrupted included files. Makes no sense to me, though. This class inherits from gradiente: #ifndef _GRADIENTE_ #define _GRADIENTE_ #include "sensor.h" using namespace std; class Gradiente : public Sensor { protected: int vActual, vMin; public: Gradiente(); ~Gradiente(); } #endif Which in turn inherits from sensor #ifndef _SENSOR_ #define _SENSOR_ #include <iostream> #include <fstream> #include <string> #include "definicoes.h" using namespace std; class Sensor { protected: int tipo; int IDsensor; bool estadoAlerta; bool estadoActivo; static int numSensores; public: Sensor(/*PARAMETROS*/); Sensor(ifstream &); ~Sensor(); int getIDsensor(); bool getEstadoAlerta(); bool getEstadoActivo(); void setEstadoAlerta(int a); void setEstadoActivo(int a); virtual void guardaSensor(ofstream &); virtual void mostraSensor(); // FUNÇÃO COMUM /* virtual int funcaoComum() = 0; virtual int funcaoComum(){return 0;};*/ }; #endif For completeness' sake, here's definicoes.h #ifndef _DEFINICOES_ #define _DEFINICOES_ const unsigned int SENSOR_MOVIMENTO = 0; const unsigned int SENSOR_SOM = 1; const unsigned int SENSOR_PRESSAO = 2; const unsigned int SENSOR_CALOR = 3; const unsigned int SENSOR_CONTACTO = 4; const unsigned int MIN_MOVIMENTO = 10; const unsigned int MIN_SOM = 10; const unsigned int MIN_PRESSAO = 10; const unsigned int MIN_CALOR = 35; #endif Any help'd be much appreciated. Thank you for your time. Thanks for your time!

  Read the article

• How to store byte[] from Android Camera onPictureTaken method within application for later use

  - by Kiel Wood

  I am writing a larger Android application and I use the camera within the app. All I want to do with the camera is have the user take a picture, then start a new activity to show that image and allow the user to decide if they want to keep the image or not. I am having the hardest time figuring out how to simply store the byte[] data from the onPictureTaken method so that I can display it to the user in the next activity. I have tried many different routes and none of them have worked. The last thing I tried was creating a globalsettings class that extends the Application class and creating a byte[] field within it to store the byte[] from the camera so that I could use it within another activity, but my global variable is still not getting set. My CameraActivity code is shown below: public class CameraActivity extends Activity { CameraPreview Preview; Intent intent; byte[] image; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.cameralayout); Preview = new CameraPreview(this); ((FrameLayout)findViewById(R.id.uxfmlayPreview)).addView(Preview); intent = new Intent(this, PostCaptureActivity.class); } public void uxbtnCaptureSnap_Click(View v) { Preview.DeviceCamera.setPreviewCallback(null); Preview.DeviceCamera.takePicture(shutterCallback, rawCallback, jpegCallback); startActivity(intent); finish(); } public void uxbtnCaptureExit_Click(View v) { Intent i = new Intent(this, ExploreMenuActivity.class); setResult(RESULT_OK); startActivity(i); finish(); } ShutterCallback shutterCallback = new ShutterCallback() { public void onShutter() {} }; PictureCallback rawCallback = new PictureCallback() { public void onPictureTaken(byte[] data, Camera camera) {} }; PictureCallback jpegCallback = new PictureCallback() { public void onPictureTaken(byte[] data, Camera camera) { ((GlobalSettings)getApplication()).setGlobalImage(data); camera.release(); camera = null; } }; } Here is my code from my PostCaptureActivity onCreate() method where I attempt to convert and set the image as the source for an imageview: public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.postcapturelayout); SnapShot = ((ImageView)findViewById(R.id.uximgSnapshot)); if(((GlobalSettings)this.getApplication()).getGlobalImage() != null) { Bitmap b = BitmapFactory.decodeByteArray(((GlobalSettings)this.getApplication()).getGlobalImage(), 0, ((GlobalSettings)this.getApplication()).getGlobalImage().length); SnapShot.setImageBitmap(b); } else { Toast.makeText(this, "Oops! Picture cannot be saved", Toast.LENGTH_SHORT).show(); } }

  Read the article

• Can SQLite file copied successfully on the data folder of an unrooted android device ?

  - by student

  I know that in order to access the data folder on the device, it needs to be rooted. However, if I just want to copy the database from my assets folder to the data folder on my device, will the copying process works on an unrooted phone? The following is my Database Helper class. From logcat, I can verify that the methods call to copyDataBase(), createDataBase() and openDataBase() are returned successfully. However, I got this error message android.database.sqlite.SQLiteException: no such table: TABLE_NAME: when my application is executing rawQuery. I'm suspecting the database file is not copied successfully (cannot be too sure as I do not have access to data folder), yet the method call to copyDatabase() are not throwing any exception. What could it be? Thanks. ps: My device is still unrooted, I hope it is not the main cause of the error. public DatabaseHelper(Context context) { super(context, DB_NAME, null, 1); this.myContext = context; } public void createDataBase() throws IOException{ boolean dbExist = checkDataBase(); String s = new Boolean(dbExist).toString(); Log.d("dbExist", s ); if(dbExist){ //do nothing - database already exist Log.d("createdatabase","DB exists so do nothing"); }else{ this.getReadableDatabase(); try { copyDataBase(); Log.d("copydatabase","Successful return frm method call!"); } catch (IOException e) { throw new Error("Error copying database"); } } } private boolean checkDataBase(){ File dbFile = new File(DB_PATH + DB_NAME); return dbFile.exists(); } private void copyDataBase() throws IOException{ //Open your local db as the input stream InputStream myInput = null; myInput = myContext.getAssets().open(DB_NAME); Log.d("copydatabase","InputStream successful!"); // Path to the just created empty db String outFileName = DB_PATH + DB_NAME; //Open the empty db as the output stream OutputStream myOutput = new FileOutputStream(outFileName); //transfer bytes from the inputfile to the outputfile byte[] buffer = new byte[1024]; int length; while ((length = myInput.read(buffer))>0){ myOutput.write(buffer, 0, length); } //Close the streams myOutput.flush(); myOutput.close(); myInput.close(); } public void openDataBase() throws SQLException{ //Open the database String myPath = DB_PATH + DB_NAME; myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY); } /* @Override public synchronized void close() { if(myDataBase != null) myDataBase.close(); super.close(); }*/ public void close() { // NOTE: openHelper must now be a member of CallDataHelper; // you currently have it as a local in your constructor if (myDataBase != null) { myDataBase.close(); } } @Override public void onCreate(SQLiteDatabase db) { } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } }

  Read the article

• Calculating the Size (in Bytes and MB) of a Oracle Coherence Cache

  - by Ricardo Ferreira

  The concept and usage of data grids are becoming very popular in this days since this type of technology are evolving very fast with some cool lead products like Oracle Coherence. Once for a while, developers need an programmatic way to calculate the total size of a specific cache that are residing in the data grid. In this post, I will show how to accomplish this using Oracle Coherence API. This example has been tested with 3.6, 3.7 and 3.7.1 versions of Oracle Coherence. To start the development of this example, you need to create a POJO ("Plain Old Java Object") that represents a data structure that will hold user data. This data structure will also create an internal fat so I call that should increase considerably the size of each instance in the heap memory. Create a Java class named "Person" as shown in the listing below. package com.oracle.coherence.domain; import java.io.Serializable; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Random; @SuppressWarnings("serial") public class Person implements Serializable { private String firstName; private String lastName; private List<Object> fat; private String email; public Person() { generateFat(); } public Person(String firstName, String lastName, String email) { setFirstName(firstName); setLastName(lastName); setEmail(email); generateFat(); } private void generateFat() { fat = new ArrayList<Object>(); Random random = new Random(); for (int i = 0; i < random.nextInt(18000); i++) { HashMap<Long, Double> internalFat = new HashMap<Long, Double>(); for (int j = 0; j < random.nextInt(10000); j++) { internalFat.put(random.nextLong(), random.nextDouble()); } fat.add(internalFat); } } public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this.firstName = firstName; } public String getLastName() { return lastName; } public void setLastName(String lastName) { this.lastName = lastName; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } } Now let's create a Java program that will start a data grid into Coherence and will create a cache named "People", that will hold people instances with sequential integer keys. Each person created in this program will trigger the execution of a custom constructor created in the People class that instantiates an internal fat (the random amount of data generated to increase the size of the object) for each person. Create a Java class named "CreatePeopleCacheAndPopulateWithData" as shown in the listing below. package com.oracle.coherence.demo; import com.oracle.coherence.domain.Person; import com.tangosol.net.CacheFactory; import com.tangosol.net.NamedCache; public class CreatePeopleCacheAndPopulateWithData { public static void main(String[] args) { // Asks Coherence for a new cache named "People"... NamedCache people = CacheFactory.getCache("People"); // Creates three people that will be putted into the data grid. Each person // generates an internal fat that should increase its size in terms of bytes... Person pessoa1 = new Person("Ricardo", "Ferreira", "[email protected]"); Person pessoa2 = new Person("Vitor", "Ferreira", "[email protected]"); Person pessoa3 = new Person("Vivian", "Ferreira", "[email protected]"); // Insert three people at the data grid... people.put(1, pessoa1); people.put(2, pessoa2); people.put(3, pessoa3); // Waits for 5 minutes until the user runs the Java program // that calculates the total size of the people cache... try { System.out.println("---> Waiting for 5 minutes for the cache size calculation..."); Thread.sleep(300000); } catch (InterruptedException ie) { ie.printStackTrace(); } } } Finally, let's create a Java program that, using the Coherence API and JMX, will calculate the total size of each cache that the data grid is currently managing. The approach used in this example was retrieve every cache that the data grid are currently managing, but if you are interested on an specific cache, the same approach can be used, you should only filter witch cache will be looked for. Create a Java class named "CalculateTheSizeOfPeopleCache" as shown in the listing below. package com.oracle.coherence.demo; import java.text.DecimalFormat; import java.util.Map; import java.util.Set; import java.util.TreeMap; import javax.management.MBeanServer; import javax.management.MBeanServerFactory; import javax.management.ObjectName; import com.tangosol.net.CacheFactory; public class CalculateTheSizeOfPeopleCache { @SuppressWarnings({ "unchecked", "rawtypes" }) private void run() throws Exception { // Enable JMX support in this Coherence data grid session... System.setProperty("tangosol.coherence.management", "all"); // Create a sample cache just to access the data grid... CacheFactory.getCache(MBeanServerFactory.class.getName()); // Gets the JMX server from Coherence data grid... MBeanServer jmxServer = getJMXServer(); // Creates a internal data structure that would maintain // the statistics from each cache in the data grid... Map cacheList = new TreeMap(); Set jmxObjectList = jmxServer.queryNames(new ObjectName("Coherence:type=Cache,*"), null); for (Object jmxObject : jmxObjectList) { ObjectName jmxObjectName = (ObjectName) jmxObject; String cacheName = jmxObjectName.getKeyProperty("name"); if (cacheName.equals(MBeanServerFactory.class.getName())) { continue; } else { cacheList.put(cacheName, new Statistics(cacheName)); } } // Updates the internal data structure with statistic data // retrieved from caches inside the in-memory data grid... Set<String> cacheNames = cacheList.keySet(); for (String cacheName : cacheNames) { Set resultSet = jmxServer.queryNames( new ObjectName("Coherence:type=Cache,name=" + cacheName + ",*"), null); for (Object resultSetRef : resultSet) { ObjectName objectName = (ObjectName) resultSetRef; if (objectName.getKeyProperty("tier").equals("back")) { int unit = (Integer) jmxServer.getAttribute(objectName, "Units"); int size = (Integer) jmxServer.getAttribute(objectName, "Size"); Statistics statistics = (Statistics) cacheList.get(cacheName); statistics.incrementUnit(unit); statistics.incrementSize(size); cacheList.put(cacheName, statistics); } } } // Finally... print the objects from the internal data // structure that represents the statistics from caches... cacheNames = cacheList.keySet(); for (String cacheName : cacheNames) { Statistics estatisticas = (Statistics) cacheList.get(cacheName); System.out.println(estatisticas); } } public MBeanServer getJMXServer() { MBeanServer jmxServer = null; for (Object jmxServerRef : MBeanServerFactory.findMBeanServer(null)) { jmxServer = (MBeanServer) jmxServerRef; if (jmxServer.getDefaultDomain().equals(DEFAULT_DOMAIN) || DEFAULT_DOMAIN.length() == 0) { break; } jmxServer = null; } if (jmxServer == null) { jmxServer = MBeanServerFactory.createMBeanServer(DEFAULT_DOMAIN); } return jmxServer; } private class Statistics { private long unit; private long size; private String cacheName; public Statistics(String cacheName) { this.cacheName = cacheName; } public void incrementUnit(long unit) { this.unit += unit; } public void incrementSize(long size) { this.size += size; } public long getUnit() { return unit; } public long getSize() { return size; } public double getUnitInMB() { return unit / (1024.0 * 1024.0); } public double getAverageSize() { return size == 0 ? 0 : unit / size; } public String toString() { StringBuffer sb = new StringBuffer(); sb.append("\nCache Statistics of '").append(cacheName).append("':\n"); sb.append(" - Total Entries of Cache -----> " + getSize()).append("\n"); sb.append(" - Used Memory (Bytes) --------> " + getUnit()).append("\n"); sb.append(" - Used Memory (MB) -----------> " + FORMAT.format(getUnitInMB())).append("\n"); sb.append(" - Object Average Size --------> " + FORMAT.format(getAverageSize())).append("\n"); return sb.toString(); } } public static void main(String[] args) throws Exception { new CalculateTheSizeOfPeopleCache().run(); } public static final DecimalFormat FORMAT = new DecimalFormat("###.###"); public static final String DEFAULT_DOMAIN = ""; public static final String DOMAIN_NAME = "Coherence"; } I've commented the overall example so, I don't think that you should get into trouble to understand it. Basically we are dealing with JMX. The first thing to do is enable JMX support for the Coherence client (ie, an JVM that will only retrieve values from the data grid and will not integrate the cluster) application. This can be done very easily using the runtime "tangosol.coherence.management" system property. Consult the Coherence documentation for JMX to understand the possible values that could be applied. The program creates an in memory data structure that holds a custom class created called "Statistics". This class represents the information that we are interested to see, which in this case are the size in bytes and in MB of the caches. An instance of this class is created for each cache that are currently managed by the data grid. Using JMX specific methods, we retrieve the information that are relevant for calculate the total size of the caches. To test this example, you should execute first the CreatePeopleCacheAndPopulateWithData.java program and after the CreatePeopleCacheAndPopulateWithData.java program. The results in the console should be something like this: 2012-06-23 13:29:31.188/4.970 Oracle Coherence 3.6.0.4 <Info> (thread=Main Thread, member=n/a): Loaded operational configuration from "jar:file:/E:/Oracle/Middleware/oepe_11gR1PS4/workspace/calcular-tamanho-cache-coherence/lib/coherence.jar!/tangosol-coherence.xml" 2012-06-23 13:29:31.219/5.001 Oracle Coherence 3.6.0.4 <Info> (thread=Main Thread, member=n/a): Loaded operational overrides from "jar:file:/E:/Oracle/Middleware/oepe_11gR1PS4/workspace/calcular-tamanho-cache-coherence/lib/coherence.jar!/tangosol-coherence-override-dev.xml" 2012-06-23 13:29:31.219/5.001 Oracle Coherence 3.6.0.4 <D5> (thread=Main Thread, member=n/a): Optional configuration override "/tangosol-coherence-override.xml" is not specified 2012-06-23 13:29:31.266/5.048 Oracle Coherence 3.6.0.4 <D5> (thread=Main Thread, member=n/a): Optional configuration override "/custom-mbeans.xml" is not specified Oracle Coherence Version 3.6.0.4 Build 19111 Grid Edition: Development mode Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. 2012-06-23 13:29:33.156/6.938 Oracle Coherence GE 3.6.0.4 <Info> (thread=Main Thread, member=n/a): Loaded Reporter configuration from "jar:file:/E:/Oracle/Middleware/oepe_11gR1PS4/workspace/calcular-tamanho-cache-coherence/lib/coherence.jar!/reports/report-group.xml" 2012-06-23 13:29:33.500/7.282 Oracle Coherence GE 3.6.0.4 <Info> (thread=Main Thread, member=n/a): Loaded cache configuration from "jar:file:/E:/Oracle/Middleware/oepe_11gR1PS4/workspace/calcular-tamanho-cache-coherence/lib/coherence.jar!/coherence-cache-config.xml" 2012-06-23 13:29:35.391/9.173 Oracle Coherence GE 3.6.0.4 <D4> (thread=Main Thread, member=n/a): TCMP bound to /192.168.177.133:8090 using SystemSocketProvider 2012-06-23 13:29:37.062/10.844 Oracle Coherence GE 3.6.0.4 <Info> (thread=Cluster, member=n/a): This Member(Id=2, Timestamp=2012-06-23 13:29:36.899, Address=192.168.177.133:8090, MachineId=55685, Location=process:244, Role=Oracle, Edition=Grid Edition, Mode=Development, CpuCount=2, SocketCount=2) joined cluster "cluster:0xC4DB" with senior Member(Id=1, Timestamp=2012-06-23 13:29:14.031, Address=192.168.177.133:8088, MachineId=55685, Location=process:1128, Role=CreatePeopleCacheAndPopulateWith, Edition=Grid Edition, Mode=Development, CpuCount=2, SocketCount=2) 2012-06-23 13:29:37.172/10.954 Oracle Coherence GE 3.6.0.4 <D5> (thread=Cluster, member=n/a): Member 1 joined Service Cluster with senior member 1 2012-06-23 13:29:37.188/10.970 Oracle Coherence GE 3.6.0.4 <D5> (thread=Cluster, member=n/a): Member 1 joined Service Management with senior member 1 2012-06-23 13:29:37.188/10.970 Oracle Coherence GE 3.6.0.4 <D5> (thread=Cluster, member=n/a): Member 1 joined Service DistributedCache with senior member 1 2012-06-23 13:29:37.188/10.970 Oracle Coherence GE 3.6.0.4 <Info> (thread=Main Thread, member=n/a): Started cluster Name=cluster:0xC4DB Group{Address=224.3.6.0, Port=36000, TTL=4} MasterMemberSet ( ThisMember=Member(Id=2, Timestamp=2012-06-23 13:29:36.899, Address=192.168.177.133:8090, MachineId=55685, Location=process:244, Role=Oracle) OldestMember=Member(Id=1, Timestamp=2012-06-23 13:29:14.031, Address=192.168.177.133:8088, MachineId=55685, Location=process:1128, Role=CreatePeopleCacheAndPopulateWith) ActualMemberSet=MemberSet(Size=2, BitSetCount=2 Member(Id=1, Timestamp=2012-06-23 13:29:14.031, Address=192.168.177.133:8088, MachineId=55685, Location=process:1128, Role=CreatePeopleCacheAndPopulateWith) Member(Id=2, Timestamp=2012-06-23 13:29:36.899, Address=192.168.177.133:8090, MachineId=55685, Location=process:244, Role=Oracle) ) RecycleMillis=1200000 RecycleSet=MemberSet(Size=0, BitSetCount=0 ) ) TcpRing{Connections=[1]} IpMonitor{AddressListSize=0} 2012-06-23 13:29:37.891/11.673 Oracle Coherence GE 3.6.0.4 <D5> (thread=Invocation:Management, member=2): Service Management joined the cluster with senior service member 1 2012-06-23 13:29:39.203/12.985 Oracle Coherence GE 3.6.0.4 <D5> (thread=DistributedCache, member=2): Service DistributedCache joined the cluster with senior service member 1 2012-06-23 13:29:39.297/13.079 Oracle Coherence GE 3.6.0.4 <D4> (thread=DistributedCache, member=2): Asking member 1 for 128 primary partitions Cache Statistics of 'People': - Total Entries of Cache -----> 3 - Used Memory (Bytes) --------> 883920 - Used Memory (MB) -----------> 0.843 - Object Average Size --------> 294640 I hope that this post could save you some time when calculate the total size of Coherence cache became a requirement for your high scalable system using data grids. See you!

  Read the article

• Understanding C# async / await (1) Compilation

  - by Dixin

  Now the async / await keywords are in C#. Just like the async and ! in F#, this new C# feature provides great convenience. There are many nice documents talking about how to use async / await in specific scenarios, like using async methods in ASP.NET 4.5 and in ASP.NET MVC 4, etc. In this article we will look at the real code working behind the syntax sugar. According to MSDN: The async modifier indicates that the method, lambda expression, or anonymous method that it modifies is asynchronous. Since lambda expression / anonymous method will be compiled to normal method, we will focus on normal async method. Preparation First of all, Some helper methods need to make up. internal class HelperMethods { internal static int Method(int arg0, int arg1) { // Do some IO. WebClient client = new WebClient(); Enumerable.Repeat("http://weblogs.asp.net/dixin", 10) .Select(client.DownloadString).ToArray(); int result = arg0 + arg1; return result; } internal static Task<int> MethodTask(int arg0, int arg1) { Task<int> task = new Task<int>(() => Method(arg0, arg1)); task.Start(); // Hot task (started task) should always be returned. return task; } internal static void Before() { } internal static void Continuation1(int arg) { } internal static void Continuation2(int arg) { } } Here Method() is a long running method doing some IO. Then MethodTask() wraps it into a Task and return that Task. Nothing special here. Await something in async method Since MethodTask() returns Task, let’s try to await it: internal class AsyncMethods { internal static async Task<int> MethodAsync(int arg0, int arg1) { int result = await HelperMethods.MethodTask(arg0, arg1); return result; } } Because we used await in the method, async must be put on the method. Now we get the first async method. According to the naming convenience, it is called MethodAsync. Of course a async method can be awaited. So we have a CallMethodAsync() to call MethodAsync(): internal class AsyncMethods { internal static async Task<int> CallMethodAsync(int arg0, int arg1) { int result = await MethodAsync(arg0, arg1); return result; } } After compilation, MethodAsync() and CallMethodAsync() becomes the same logic. This is the code of MethodAsyc(): internal class CompiledAsyncMethods { [DebuggerStepThrough] [AsyncStateMachine(typeof(MethodAsyncStateMachine))] // async internal static /*async*/ Task<int> MethodAsync(int arg0, int arg1) { MethodAsyncStateMachine methodAsyncStateMachine = new MethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Builder = AsyncTaskMethodBuilder<int>.Create(), State = -1 }; methodAsyncStateMachine.Builder.Start(ref methodAsyncStateMachine); return methodAsyncStateMachine.Builder.Task; } } It just creates and starts a state machine MethodAsyncStateMachine: [CompilerGenerated] [StructLayout(LayoutKind.Auto)] internal struct MethodAsyncStateMachine : IAsyncStateMachine { public int State; public AsyncTaskMethodBuilder<int> Builder; public int Arg0; public int Arg1; public int Result; private TaskAwaiter<int> awaitor; void IAsyncStateMachine.MoveNext() { try { if (this.State != 0) { this.awaitor = HelperMethods.MethodTask(this.Arg0, this.Arg1).GetAwaiter(); if (!this.awaitor.IsCompleted) { this.State = 0; this.Builder.AwaitUnsafeOnCompleted(ref this.awaitor, ref this); return; } } else { this.State = -1; } this.Result = this.awaitor.GetResult(); } catch (Exception exception) { this.State = -2; this.Builder.SetException(exception); return; } this.State = -2; this.Builder.SetResult(this.Result); } [DebuggerHidden] void IAsyncStateMachine.SetStateMachine(IAsyncStateMachine param0) { this.Builder.SetStateMachine(param0); } } The generated code has been cleaned up so it is readable and can be compiled. Several things can be observed here: The async modifier is gone, which shows, unlike other modifiers (e.g. static), there is no such IL/CLR level “async” stuff. It becomes a AsyncStateMachineAttribute. This is similar to the compilation of extension method. The generated state machine is very similar to the state machine of C# yield syntax sugar. The local variables (arg0, arg1, result) are compiled to fields of the state machine. The real code (await HelperMethods.MethodTask(arg0, arg1)) is compiled into MoveNext(): HelperMethods.MethodTask(this.Arg0, this.Arg1).GetAwaiter(). CallMethodAsync() will create and start its own state machine CallMethodAsyncStateMachine: internal class CompiledAsyncMethods { [DebuggerStepThrough] [AsyncStateMachine(typeof(CallMethodAsyncStateMachine))] // async internal static /*async*/ Task<int> CallMethodAsync(int arg0, int arg1) { CallMethodAsyncStateMachine callMethodAsyncStateMachine = new CallMethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Builder = AsyncTaskMethodBuilder<int>.Create(), State = -1 }; callMethodAsyncStateMachine.Builder.Start(ref callMethodAsyncStateMachine); return callMethodAsyncStateMachine.Builder.Task; } } CallMethodAsyncStateMachine has the same logic as MethodAsyncStateMachine above. The detail of the state machine will be discussed soon. Now it is clear that: async /await is a C# level syntax sugar. There is no difference to await a async method or a normal method. A method returning Task will be awaitable. State machine and continuation To demonstrate more details in the state machine, a more complex method is created: internal class AsyncMethods { internal static async Task<int> MultiCallMethodAsync(int arg0, int arg1, int arg2, int arg3) { HelperMethods.Before(); int resultOfAwait1 = await MethodAsync(arg0, arg1); HelperMethods.Continuation1(resultOfAwait1); int resultOfAwait2 = await MethodAsync(arg2, arg3); HelperMethods.Continuation2(resultOfAwait2); int resultToReturn = resultOfAwait1 + resultOfAwait2; return resultToReturn; } } In this method: There are multiple awaits. There are code before the awaits, and continuation code after each await After compilation, this multi-await method becomes the same as above single-await methods: internal class CompiledAsyncMethods { [DebuggerStepThrough] [AsyncStateMachine(typeof(MultiCallMethodAsyncStateMachine))] // async internal static /*async*/ Task<int> MultiCallMethodAsync(int arg0, int arg1, int arg2, int arg3) { MultiCallMethodAsyncStateMachine multiCallMethodAsyncStateMachine = new MultiCallMethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Arg2 = arg2, Arg3 = arg3, Builder = AsyncTaskMethodBuilder<int>.Create(), State = -1 }; multiCallMethodAsyncStateMachine.Builder.Start(ref multiCallMethodAsyncStateMachine); return multiCallMethodAsyncStateMachine.Builder.Task; } } It creates and starts one single state machine, MultiCallMethodAsyncStateMachine: [CompilerGenerated] [StructLayout(LayoutKind.Auto)] internal struct MultiCallMethodAsyncStateMachine : IAsyncStateMachine { public int State; public AsyncTaskMethodBuilder<int> Builder; public int Arg0; public int Arg1; public int Arg2; public int Arg3; public int ResultOfAwait1; public int ResultOfAwait2; public int ResultToReturn; private TaskAwaiter<int> awaiter; void IAsyncStateMachine.MoveNext() { try { switch (this.State) { case -1: HelperMethods.Before(); this.awaiter = AsyncMethods.MethodAsync(this.Arg0, this.Arg1).GetAwaiter(); if (!this.awaiter.IsCompleted) { this.State = 0; this.Builder.AwaitUnsafeOnCompleted(ref this.awaiter, ref this); } break; case 0: this.ResultOfAwait1 = this.awaiter.GetResult(); HelperMethods.Continuation1(this.ResultOfAwait1); this.awaiter = AsyncMethods.MethodAsync(this.Arg2, this.Arg3).GetAwaiter(); if (!this.awaiter.IsCompleted) { this.State = 1; this.Builder.AwaitUnsafeOnCompleted(ref this.awaiter, ref this); } break; case 1: this.ResultOfAwait2 = this.awaiter.GetResult(); HelperMethods.Continuation2(this.ResultOfAwait2); this.ResultToReturn = this.ResultOfAwait1 + this.ResultOfAwait2; this.State = -2; this.Builder.SetResult(this.ResultToReturn); break; } } catch (Exception exception) { this.State = -2; this.Builder.SetException(exception); } } [DebuggerHidden] void IAsyncStateMachine.SetStateMachine(IAsyncStateMachine stateMachine) { this.Builder.SetStateMachine(stateMachine); } } The above code is already cleaned up, but there are still a lot of things. More clean up can be done, and the state machine can be very simple: [CompilerGenerated] [StructLayout(LayoutKind.Auto)] internal struct MultiCallMethodAsyncStateMachine : IAsyncStateMachine { // State: // -1: Begin // 0: 1st await is done // 1: 2nd await is done // ... // -2: End public int State; public TaskCompletionSource<int> ResultToReturn; // int resultToReturn ... public int Arg0; // int Arg0 public int Arg1; // int arg1 public int Arg2; // int arg2 public int Arg3; // int arg3 public int ResultOfAwait1; // int resultOfAwait1 ... public int ResultOfAwait2; // int resultOfAwait2 ... private Task<int> currentTaskToAwait; /// <summary> /// Moves the state machine to its next state. /// </summary> void IAsyncStateMachine.MoveNext() { try { switch (this.State) { // Orginal code is splitted by "case"s: // case -1: // HelperMethods.Before(); // MethodAsync(Arg0, arg1); // case 0: // int resultOfAwait1 = await ... // HelperMethods.Continuation1(resultOfAwait1); // MethodAsync(arg2, arg3); // case 1: // int resultOfAwait2 = await ... // HelperMethods.Continuation2(resultOfAwait2); // int resultToReturn = resultOfAwait1 + resultOfAwait2; // return resultToReturn; case -1: // -1 is begin. HelperMethods.Before(); // Code before 1st await. this.currentTaskToAwait = AsyncMethods.MethodAsync(this.Arg0, this.Arg1); // 1st task to await // When this.currentTaskToAwait is done, run this.MoveNext() and go to case 0. this.State = 0; IAsyncStateMachine this1 = this; // Cannot use "this" in lambda so create a local variable. this.currentTaskToAwait.ContinueWith(_ => this1.MoveNext()); // Callback break; case 0: // Now 1st await is done. this.ResultOfAwait1 = this.currentTaskToAwait.Result; // Get 1st await's result. HelperMethods.Continuation1(this.ResultOfAwait1); // Code after 1st await and before 2nd await. this.currentTaskToAwait = AsyncMethods.MethodAsync(this.Arg2, this.Arg3); // 2nd task to await // When this.currentTaskToAwait is done, run this.MoveNext() and go to case 1. this.State = 1; IAsyncStateMachine this2 = this; // Cannot use "this" in lambda so create a local variable. this.currentTaskToAwait.ContinueWith(_ => this2.MoveNext()); // Callback break; case 1: // Now 2nd await is done. this.ResultOfAwait2 = this.currentTaskToAwait.Result; // Get 2nd await's result. HelperMethods.Continuation2(this.ResultOfAwait2); // Code after 2nd await. int resultToReturn = this.ResultOfAwait1 + this.ResultOfAwait2; // Code after 2nd await. // End with resultToReturn. this.State = -2; // -2 is end. this.ResultToReturn.SetResult(resultToReturn); break; } } catch (Exception exception) { // End with exception. this.State = -2; // -2 is end. this.ResultToReturn.SetException(exception); } } /// <summary> /// Configures the state machine with a heap-allocated replica. /// </summary> /// <param name="stateMachine">The heap-allocated replica.</param> [DebuggerHidden] void IAsyncStateMachine.SetStateMachine(IAsyncStateMachine stateMachine) { // No core logic. } } Only Task and TaskCompletionSource are involved in this version. And MultiCallMethodAsync() can be simplified to: [DebuggerStepThrough] [AsyncStateMachine(typeof(MultiCallMethodAsyncStateMachine))] // async internal static /*async*/ Task<int> MultiCallMethodAsync_(int arg0, int arg1, int arg2, int arg3) { MultiCallMethodAsyncStateMachine multiCallMethodAsyncStateMachine = new MultiCallMethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Arg2 = arg2, Arg3 = arg3, ResultToReturn = new TaskCompletionSource<int>(), // -1: Begin // 0: 1st await is done // 1: 2nd await is done // ... // -2: End State = -1 }; (multiCallMethodAsyncStateMachine as IAsyncStateMachine).MoveNext(); // Original code are in this method. return multiCallMethodAsyncStateMachine.ResultToReturn.Task; } Now the whole state machine becomes very clear - it is about callback: Original code are split into pieces by “await”s, and each piece is put into each “case” in the state machine. Here the 2 awaits split the code into 3 pieces, so there are 3 “case”s. The “piece”s are chained by callback, that is done by Builder.AwaitUnsafeOnCompleted(callback), or currentTaskToAwait.ContinueWith(callback) in the simplified code. A previous “piece” will end with a Task (which is to be awaited), when the task is done, it will callback the next “piece”. The state machine’s state works with the “case”s to ensure the code “piece”s executes one after another. Callback Since it is about callback, the simplification  can go even further – the entire state machine can be completely purged. Now MultiCallMethodAsync() becomes: internal static Task<int> MultiCallMethodAsync(int arg0, int arg1, int arg2, int arg3) { TaskCompletionSource<int> taskCompletionSource = new TaskCompletionSource<int>(); try { // Oringinal code begins. HelperMethods.Before(); MethodAsync(arg0, arg1).ContinueWith(await1 => { int resultOfAwait1 = await1.Result; HelperMethods.Continuation1(resultOfAwait1); MethodAsync(arg2, arg3).ContinueWith(await2 => { int resultOfAwait2 = await2.Result; HelperMethods.Continuation2(resultOfAwait2); int resultToReturn = resultOfAwait1 + resultOfAwait2; // Oringinal code ends. taskCompletionSource.SetResult(resultToReturn); }); }); } catch (Exception exception) { taskCompletionSource.SetException(exception); } return taskCompletionSource.Task; } Please compare with the original async / await code: HelperMethods.Before(); int resultOfAwait1 = await MethodAsync(arg0, arg1); HelperMethods.Continuation1(resultOfAwait1); int resultOfAwait2 = await MethodAsync(arg2, arg3); HelperMethods.Continuation2(resultOfAwait2); int resultToReturn = resultOfAwait1 + resultOfAwait2; return resultToReturn; Yeah that is the magic of C# async / await: Await is literally pretending to wait. In a await expression, a Task object will be return immediately so that caller is not blocked. The continuation code is compiled as that Task’s callback code. When that task is done, continuation code will execute. Please notice that many details inside the state machine are omitted for simplicity, like context caring, etc. If you want to have a detailed picture, please do check out the source code of AsyncTaskMethodBuilder and TaskAwaiter.

  Read the article

• Testing Entity Framework applications, pt. 3: NDbUnit

  - by Thomas Weller

  This is the third of a three part series that deals with the issue of faking test data in the context of a legacy app that was built with Microsoft's Entity Framework (EF) on top of an MS SQL Server database – a scenario that can be found very often. Please read the first part for a description of the sample application, a discussion of some general aspects of unit testing in a database context, and of some more specific aspects of the here discussed EF/MSSQL combination. Lately, I wondered how you would ‘mock’ the data layer of a legacy application, when this data layer is made up of an MS Entity Framework (EF) model in combination with a MS SQL Server database. Originally, this question came up in the context of how you could enable higher-level integration tests (automated UI tests, to be exact) for a legacy application that uses this EF/MSSQL combo as its data store mechanism – a not so uncommon scenario. The question sparked my interest, and I decided to dive into it somewhat deeper. What I've found out is, in short, that it's not very easy and straightforward to do it – but it can be done. The two strategies that are best suited to fit the bill involve using either the (commercial) Typemock Isolator tool or the (free) NDbUnit framework. The use of Typemock was discussed in the previous post, this post now will present the NDbUnit approach... NDbUnit is an Apache 2.0-licensed open-source project, and like so many other Nxxx tools and frameworks, it is basically a C#/.NET port of the corresponding Java version (DbUnit namely). In short, it helps you in flexibly managing the state of a database in that it lets you easily perform basic operations (like e.g. Insert, Delete, Refresh, DeleteAll)  against your database and, most notably, lets you feed it with data from external xml files. Let's have a look at how things can be done with the help of this framework. Preparing the test data Compared to Typemock, using NDbUnit implies a totally different approach to meet our testing needs.  So the here described testing scenario requires an instance of an SQL Server database in operation, and it also means that the Entity Framework model that sits on top of this database is completely unaffected. First things first: For its interactions with the database, NDbUnit relies on a .NET Dataset xsd file. See Step 1 of their Quick Start Guide for a description of how to create one. With this prerequisite in place then, the test fixture's setup code could look something like this: [TestFixture, TestsOn(typeof(PersonRepository))] [Metadata("NDbUnit Quickstart URL",           "http://code.google.com/p/ndbunit/wiki/QuickStartGuide")] [Description("Uses the NDbUnit library to provide test data to a local database.")] public class PersonRepositoryFixture {     #region Constants     private const string XmlSchema = @"..\..\TestData\School.xsd";     #endregion // Constants     #region Fields     private SchoolEntities _schoolContext;     private PersonRepository _personRepository;     private INDbUnitTest _database;     #endregion // Fields     #region Setup/TearDown     [FixtureSetUp]     public void FixtureSetUp()     {         var connectionString = ConfigurationManager.ConnectionStrings["School_Test"].ConnectionString;         _database = new SqlDbUnitTest(connectionString);         _database.ReadXmlSchema(XmlSchema);         var entityConnectionStringBuilder = new EntityConnectionStringBuilder         {             Metadata = "res://*/School.csdl|res://*/School.ssdl|res://*/School.msl",             Provider = "System.Data.SqlClient",             ProviderConnectionString = connectionString         };         _schoolContext = new SchoolEntities(entityConnectionStringBuilder.ConnectionString);         _personRepository = new PersonRepository(this._schoolContext);     }     [FixtureTearDown]     public void FixtureTearDown()     {         _database.PerformDbOperation(DbOperationFlag.DeleteAll);         _schoolContext.Dispose();     }     ...  As you can see, there is slightly more fixture setup code involved if your tests are using NDbUnit to provide the test data: Because we're dealing with a physical database instance here, we first need to pick up the test-specific connection string from the test assemblies' App.config, then initialize an NDbUnit helper object with this connection along with the provided xsd file, and also set up the SchoolEntities and the PersonRepository instances accordingly. The _database field (an instance of the INdUnitTest interface) will be our single access point to the underlying database: We use it to perform all the required operations against the data store. To have a flexible mechanism to easily insert data into the database, we can write a helper method like this: private void InsertTestData(params string[] dataFileNames) {     _database.PerformDbOperation(DbOperationFlag.DeleteAll);     if (dataFileNames == null)     {         return;     }     try     {         foreach (string fileName in dataFileNames)         {             if (!File.Exists(fileName))             {                 throw new FileNotFoundException(Path.GetFullPath(fileName));             }             _database.ReadXml(fileName);             _database.PerformDbOperation(DbOperationFlag.InsertIdentity);         }     }     catch     {         _database.PerformDbOperation(DbOperationFlag.DeleteAll);         throw;     } } This lets us easily insert test data from xml files, in any number and in a  controlled order (which is important because we eventually must fulfill referential constraints, or we must account for some other stuff that imposes a specific ordering on data insertion). Again, as with Typemock, I won't go into API details here. - Unfortunately, there isn't too much documentation for NDbUnit anyway, other than the already mentioned Quick Start Guide (and the source code itself, of course) - a not so uncommon problem with smaller Open Source Projects. Last not least, we need to provide the required test data in xml form. A snippet for data from the People table might look like this, for example: <?xml version="1.0" encoding="utf-8" ?> <School xmlns="http://tempuri.org/School.xsd">   <Person>     <PersonID>1</PersonID>     <LastName>Abercrombie</LastName>     <FirstName>Kim</FirstName>     <HireDate>1995-03-11T00:00:00</HireDate>   </Person>   <Person>     <PersonID>2</PersonID>     <LastName>Barzdukas</LastName>     <FirstName>Gytis</FirstName>     <EnrollmentDate>2005-09-01T00:00:00</EnrollmentDate>   </Person>   <Person>     ... You can also have data from various tables in one single xml file, if that's appropriate for you (but beware of the already mentioned ordering issues). It's true that your test assembly may end up with dozens of such xml files, each containing quite a big amount of text data. But because the files are of very low complexity, and with the help of a little bit of Copy/Paste and Excel magic, this appears to be well manageable. Executing some basic tests Here are some of the possible tests that can be written with the above preparations in place: private const string People = @"..\..\TestData\School.People.xml"; ... [Test, MultipleAsserts, TestsOn("PersonRepository.GetNameList")] public void GetNameList_ListOrdering_ReturnsTheExpectedFullNames() {     InsertTestData(People);     List<string> names =         _personRepository.GetNameList(NameOrdering.List);     Assert.Count(34, names);     Assert.AreEqual("Abercrombie, Kim", names.First());     Assert.AreEqual("Zheng, Roger", names.Last()); } [Test, MultipleAsserts, TestsOn("PersonRepository.GetNameList")] [DependsOn("RemovePerson_CalledOnce_DecreasesCountByOne")] public void GetNameList_NormalOrdering_ReturnsTheExpectedFullNames() {     InsertTestData(People);     List<string> names =         _personRepository.GetNameList(NameOrdering.Normal);     Assert.Count(34, names);     Assert.AreEqual("Alexandra Walker", names.First());     Assert.AreEqual("Yan Li", names.Last()); } [Test, TestsOn("PersonRepository.AddPerson")] public void AddPerson_CalledOnce_IncreasesCountByOne() {     InsertTestData(People);     int count = _personRepository.Count;     _personRepository.AddPerson(new Person { FirstName = "Thomas", LastName = "Weller" });     Assert.AreEqual(count + 1, _personRepository.Count); } [Test, TestsOn("PersonRepository.RemovePerson")] public void RemovePerson_CalledOnce_DecreasesCountByOne() {     InsertTestData(People);     int count = _personRepository.Count;     _personRepository.RemovePerson(new Person { PersonID = 33 });     Assert.AreEqual(count - 1, _personRepository.Count); } Not much difference here compared to the corresponding Typemock versions, except that we had to do a bit more preparational work (and also it was harder to get the required knowledge). But this picture changes quite dramatically if we look at some more demanding test cases: Ok, and what if things are becoming somewhat more complex? Tests like the above ones represent the 'easy' scenarios. They may account for the biggest portion of real-world use cases of the application, and they are important to make sure that it is generally sound. But usually, all these nasty little bugs originate from the more complex parts of our code, or they occur when something goes wrong. So, for a testing strategy to be of real practical use, it is especially important to see how easy or difficult it is to mimick a scenario which represents a more complex or exceptional case. The following test, for example, deals with the case that there is some sort of invalid input from the caller: [Test, MultipleAsserts, TestsOn("PersonRepository.GetCourseMembers")] [Row(null, typeof(ArgumentNullException))] [Row("", typeof(ArgumentException))] [Row("NotExistingCourse", typeof(ArgumentException))] public void GetCourseMembers_WithGivenVariousInvalidValues_Throws(string courseTitle, Type expectedInnerExceptionType) {     var exception = Assert.Throws<RepositoryException>(() =>                                 _personRepository.GetCourseMembers(courseTitle));     Assert.IsInstanceOfType(expectedInnerExceptionType, exception.InnerException); } Apparently, this test doesn't need an 'Arrange' part at all (see here for the same test with the Typemock tool). It acts just like any other client code, and all the required business logic comes from the database itself. This doesn't always necessarily mean that there is less complexity, but only that the complexity happens in a different part of your test resources (in the xml files namely, where you sometimes have to spend a lot of effort for carefully preparing the required test data). Another example, which relies on an underlying 1-n relationship, might be this: [Test, MultipleAsserts, TestsOn("PersonRepository.GetCourseMembers")] public void GetCourseMembers_WhenGivenAnExistingCourse_ReturnsListOfStudents() {     InsertTestData(People, Course, Department, StudentGrade);     List<Person> persons = _personRepository.GetCourseMembers("Macroeconomics");     Assert.Count(4, persons);     Assert.ForAll(         persons,         @p => new[] { 10, 11, 12, 14 }.Contains(@p.PersonID),         "Person has none of the expected IDs."); } If you compare this test to its corresponding Typemock version, you immediately see that the test itself is much simpler, easier to read, and thus much more intention-revealing. The complexity here lies hidden behind the call to the InsertTestData() helper method and the content of the used xml files with the test data. And also note that you might have to provide additional data which are not even directly relevant to your test, but are required only to fulfill some integrity needs of the underlying database. Conclusion The first thing to notice when comparing the NDbUnit approach to its Typemock counterpart obviously deals with performance: Of course, NDbUnit is much slower than Typemock. Technically,  it doesn't even make sense to compare the two tools. But practically, it may well play a role and could or could not be an issue, depending on how much tests you have of this kind, how often you run them, and what role they play in your development cycle. Also, because the dataset from the required xsd file must fully match the database schema (even in parts that otherwise wouldn't be relevant to you), it can be quite cumbersome to be in a team where different people are working with the database in parallel. My personal experience is – as already said in the first part – that Typemock gives you a better development experience in a 'dynamic' scenario (when you're working in some kind of TDD-style, you're oftentimes executing the tests from your dev box, and your database schema changes frequently), whereas the NDbUnit approach is a good and solid solution in more 'static' development scenarios (when you need to execute the tests less frequently or only on a separate build server, and/or the underlying database schema can be kept relatively stable), for example some variations of higher-level integration or User-Acceptance tests. But in any case, opening Entity Framework based applications for testing requires a fair amount of resources, planning, and preparational work – it's definitely not the kind of stuff that you would call 'easy to test'. Hopefully, future versions of EF will take testing concerns into account. Otherwise, I don't see too much of a future for the framework in the long run, even though it's quite popular at the moment... The sample solution A sample solution (VS 2010) with the code from this article series is available via my Bitbucket account from here (Bitbucket is a hosting site for Mercurial repositories. The repositories may also be accessed with the Git and Subversion SCMs - consult the documentation for details. In addition, it is possible to download the solution simply as a zipped archive – via the 'get source' button on the very right.). The solution contains some more tests against the PersonRepository class, which are not shown here. Also, it contains database scripts to create and fill the School sample database. To compile and run, the solution expects the Gallio/MbUnit framework to be installed (which is free and can be downloaded from here), the NDbUnit framework (which is also free and can be downloaded from here), and the Typemock Isolator tool (a fully functional 30day-trial is available here). Moreover, you will need an instance of the Microsoft SQL Server DBMS, and you will have to adapt the connection strings in the test projects App.config files accordingly.

  Read the article

• Understanding C# async / await (1) Compilation

  - by Dixin

  Now the async / await keywords are in C#. Just like the async and ! in F#, this new C# feature provides great convenience. There are many nice documents talking about how to use async / await in specific scenarios, like using async methods in ASP.NET 4.5 and in ASP.NET MVC 4, etc. In this article we will look at the real code working behind the syntax sugar. According to MSDN: The async modifier indicates that the method, lambda expression, or anonymous method that it modifies is asynchronous. Since lambda expression / anonymous method will be compiled to normal method, we will focus on normal async method. Preparation First of all, Some helper methods need to make up. internal class HelperMethods { internal static int Method(int arg0, int arg1) { // Do some IO. WebClient client = new WebClient(); Enumerable.Repeat("http://weblogs.asp.net/dixin", 10) .Select(client.DownloadString).ToArray(); int result = arg0 + arg1; return result; } internal static Task<int> MethodTask(int arg0, int arg1) { Task<int> task = new Task<int>(() => Method(arg0, arg1)); task.Start(); // Hot task (started task) should always be returned. return task; } internal static void Before() { } internal static void Continuation1(int arg) { } internal static void Continuation2(int arg) { } } Here Method() is a long running method doing some IO. Then MethodTask() wraps it into a Task and return that Task. Nothing special here. Await something in async method Since MethodTask() returns Task, let’s try to await it: internal class AsyncMethods { internal static async Task<int> MethodAsync(int arg0, int arg1) { int result = await HelperMethods.MethodTask(arg0, arg1); return result; } } Because we used await in the method, async must be put on the method. Now we get the first async method. According to the naming convenience, it is named MethodAsync. Of course a async method can be awaited. So we have a CallMethodAsync() to call MethodAsync(): internal class AsyncMethods { internal static async Task<int> CallMethodAsync(int arg0, int arg1) { int result = await MethodAsync(arg0, arg1); return result; } } After compilation, MethodAsync() and CallMethodAsync() becomes the same logic. This is the code of MethodAsyc(): internal class CompiledAsyncMethods { [DebuggerStepThrough] [AsyncStateMachine(typeof(MethodAsyncStateMachine))] // async internal static /*async*/ Task<int> MethodAsync(int arg0, int arg1) { MethodAsyncStateMachine methodAsyncStateMachine = new MethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Builder = AsyncTaskMethodBuilder<int>.Create(), State = -1 }; methodAsyncStateMachine.Builder.Start(ref methodAsyncStateMachine); return methodAsyncStateMachine.Builder.Task; } } It just creates and starts a state machine, MethodAsyncStateMachine: [CompilerGenerated] [StructLayout(LayoutKind.Auto)] internal struct MethodAsyncStateMachine : IAsyncStateMachine { public int State; public AsyncTaskMethodBuilder<int> Builder; public int Arg0; public int Arg1; public int Result; private TaskAwaiter<int> awaitor; void IAsyncStateMachine.MoveNext() { try { if (this.State != 0) { this.awaitor = HelperMethods.MethodTask(this.Arg0, this.Arg1).GetAwaiter(); if (!this.awaitor.IsCompleted) { this.State = 0; this.Builder.AwaitUnsafeOnCompleted(ref this.awaitor, ref this); return; } } else { this.State = -1; } this.Result = this.awaitor.GetResult(); } catch (Exception exception) { this.State = -2; this.Builder.SetException(exception); return; } this.State = -2; this.Builder.SetResult(this.Result); } [DebuggerHidden] void IAsyncStateMachine.SetStateMachine(IAsyncStateMachine param0) { this.Builder.SetStateMachine(param0); } } The generated code has been refactored, so it is readable and can be compiled. Several things can be observed here: The async modifier is gone, which shows, unlike other modifiers (e.g. static), there is no such IL/CLR level “async” stuff. It becomes a AsyncStateMachineAttribute. This is similar to the compilation of extension method. The generated state machine is very similar to the state machine of C# yield syntax sugar. The local variables (arg0, arg1, result) are compiled to fields of the state machine. The real code (await HelperMethods.MethodTask(arg0, arg1)) is compiled into MoveNext(): HelperMethods.MethodTask(this.Arg0, this.Arg1).GetAwaiter(). CallMethodAsync() will create and start its own state machine CallMethodAsyncStateMachine: internal class CompiledAsyncMethods { [DebuggerStepThrough] [AsyncStateMachine(typeof(CallMethodAsyncStateMachine))] // async internal static /*async*/ Task<int> CallMethodAsync(int arg0, int arg1) { CallMethodAsyncStateMachine callMethodAsyncStateMachine = new CallMethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Builder = AsyncTaskMethodBuilder<int>.Create(), State = -1 }; callMethodAsyncStateMachine.Builder.Start(ref callMethodAsyncStateMachine); return callMethodAsyncStateMachine.Builder.Task; } } CallMethodAsyncStateMachine has the same logic as MethodAsyncStateMachine above. The detail of the state machine will be discussed soon. Now it is clear that: async /await is a C# language level syntax sugar. There is no difference to await a async method or a normal method. As long as a method returns Task, it is awaitable. State machine and continuation To demonstrate more details in the state machine, a more complex method is created: internal class AsyncMethods { internal static async Task<int> MultiCallMethodAsync(int arg0, int arg1, int arg2, int arg3) { HelperMethods.Before(); int resultOfAwait1 = await MethodAsync(arg0, arg1); HelperMethods.Continuation1(resultOfAwait1); int resultOfAwait2 = await MethodAsync(arg2, arg3); HelperMethods.Continuation2(resultOfAwait2); int resultToReturn = resultOfAwait1 + resultOfAwait2; return resultToReturn; } } In this method: There are multiple awaits. There are code before the awaits, and continuation code after each await After compilation, this multi-await method becomes the same as above single-await methods: internal class CompiledAsyncMethods { [DebuggerStepThrough] [AsyncStateMachine(typeof(MultiCallMethodAsyncStateMachine))] // async internal static /*async*/ Task<int> MultiCallMethodAsync(int arg0, int arg1, int arg2, int arg3) { MultiCallMethodAsyncStateMachine multiCallMethodAsyncStateMachine = new MultiCallMethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Arg2 = arg2, Arg3 = arg3, Builder = AsyncTaskMethodBuilder<int>.Create(), State = -1 }; multiCallMethodAsyncStateMachine.Builder.Start(ref multiCallMethodAsyncStateMachine); return multiCallMethodAsyncStateMachine.Builder.Task; } } It creates and starts one single state machine, MultiCallMethodAsyncStateMachine: [CompilerGenerated] [StructLayout(LayoutKind.Auto)] internal struct MultiCallMethodAsyncStateMachine : IAsyncStateMachine { public int State; public AsyncTaskMethodBuilder<int> Builder; public int Arg0; public int Arg1; public int Arg2; public int Arg3; public int ResultOfAwait1; public int ResultOfAwait2; public int ResultToReturn; private TaskAwaiter<int> awaiter; void IAsyncStateMachine.MoveNext() { try { switch (this.State) { case -1: HelperMethods.Before(); this.awaiter = AsyncMethods.MethodAsync(this.Arg0, this.Arg1).GetAwaiter(); if (!this.awaiter.IsCompleted) { this.State = 0; this.Builder.AwaitUnsafeOnCompleted(ref this.awaiter, ref this); } break; case 0: this.ResultOfAwait1 = this.awaiter.GetResult(); HelperMethods.Continuation1(this.ResultOfAwait1); this.awaiter = AsyncMethods.MethodAsync(this.Arg2, this.Arg3).GetAwaiter(); if (!this.awaiter.IsCompleted) { this.State = 1; this.Builder.AwaitUnsafeOnCompleted(ref this.awaiter, ref this); } break; case 1: this.ResultOfAwait2 = this.awaiter.GetResult(); HelperMethods.Continuation2(this.ResultOfAwait2); this.ResultToReturn = this.ResultOfAwait1 + this.ResultOfAwait2; this.State = -2; this.Builder.SetResult(this.ResultToReturn); break; } } catch (Exception exception) { this.State = -2; this.Builder.SetException(exception); } } [DebuggerHidden] void IAsyncStateMachine.SetStateMachine(IAsyncStateMachine stateMachine) { this.Builder.SetStateMachine(stateMachine); } } Once again, the above state machine code is already refactored, but it still has a lot of things. More clean up can be done if we only keep the core logic, and the state machine can become very simple: [CompilerGenerated] [StructLayout(LayoutKind.Auto)] internal struct MultiCallMethodAsyncStateMachine : IAsyncStateMachine { // State: // -1: Begin // 0: 1st await is done // 1: 2nd await is done // ... // -2: End public int State; public TaskCompletionSource<int> ResultToReturn; // int resultToReturn ... public int Arg0; // int Arg0 public int Arg1; // int arg1 public int Arg2; // int arg2 public int Arg3; // int arg3 public int ResultOfAwait1; // int resultOfAwait1 ... public int ResultOfAwait2; // int resultOfAwait2 ... private Task<int> currentTaskToAwait; /// <summary> /// Moves the state machine to its next state. /// </summary> public void MoveNext() // IAsyncStateMachine member. { try { switch (this.State) { // Original code is split by "await"s into "case"s: // case -1: // HelperMethods.Before(); // MethodAsync(Arg0, arg1); // case 0: // int resultOfAwait1 = await ... // HelperMethods.Continuation1(resultOfAwait1); // MethodAsync(arg2, arg3); // case 1: // int resultOfAwait2 = await ... // HelperMethods.Continuation2(resultOfAwait2); // int resultToReturn = resultOfAwait1 + resultOfAwait2; // return resultToReturn; case -1: // -1 is begin. HelperMethods.Before(); // Code before 1st await. this.currentTaskToAwait = AsyncMethods.MethodAsync(this.Arg0, this.Arg1); // 1st task to await // When this.currentTaskToAwait is done, run this.MoveNext() and go to case 0. this.State = 0; MultiCallMethodAsyncStateMachine that1 = this; // Cannot use "this" in lambda so create a local variable. this.currentTaskToAwait.ContinueWith(_ => that1.MoveNext()); break; case 0: // Now 1st await is done. this.ResultOfAwait1 = this.currentTaskToAwait.Result; // Get 1st await's result. HelperMethods.Continuation1(this.ResultOfAwait1); // Code after 1st await and before 2nd await. this.currentTaskToAwait = AsyncMethods.MethodAsync(this.Arg2, this.Arg3); // 2nd task to await // When this.currentTaskToAwait is done, run this.MoveNext() and go to case 1. this.State = 1; MultiCallMethodAsyncStateMachine that2 = this; this.currentTaskToAwait.ContinueWith(_ => that2.MoveNext()); break; case 1: // Now 2nd await is done. this.ResultOfAwait2 = this.currentTaskToAwait.Result; // Get 2nd await's result. HelperMethods.Continuation2(this.ResultOfAwait2); // Code after 2nd await. int resultToReturn = this.ResultOfAwait1 + this.ResultOfAwait2; // Code after 2nd await. // End with resultToReturn. this.State = -2; // -2 is end. this.ResultToReturn.SetResult(resultToReturn); break; } } catch (Exception exception) { // End with exception. this.State = -2; // -2 is end. this.ResultToReturn.SetException(exception); } } /// <summary> /// Configures the state machine with a heap-allocated replica. /// </summary> /// <param name="stateMachine">The heap-allocated replica.</param> [DebuggerHidden] public void SetStateMachine(IAsyncStateMachine stateMachine) // IAsyncStateMachine member. { // No core logic. } } Only Task and TaskCompletionSource are involved in this version. And MultiCallMethodAsync() can be simplified to: [DebuggerStepThrough] [AsyncStateMachine(typeof(MultiCallMethodAsyncStateMachine))] // async internal static /*async*/ Task<int> MultiCallMethodAsync(int arg0, int arg1, int arg2, int arg3) { MultiCallMethodAsyncStateMachine multiCallMethodAsyncStateMachine = new MultiCallMethodAsyncStateMachine() { Arg0 = arg0, Arg1 = arg1, Arg2 = arg2, Arg3 = arg3, ResultToReturn = new TaskCompletionSource<int>(), // -1: Begin // 0: 1st await is done // 1: 2nd await is done // ... // -2: End State = -1 }; multiCallMethodAsyncStateMachine.MoveNext(); // Original code are moved into this method. return multiCallMethodAsyncStateMachine.ResultToReturn.Task; } Now the whole state machine becomes very clean - it is about callback: Original code are split into pieces by “await”s, and each piece is put into each “case” in the state machine. Here the 2 awaits split the code into 3 pieces, so there are 3 “case”s. The “piece”s are chained by callback, that is done by Builder.AwaitUnsafeOnCompleted(callback), or currentTaskToAwait.ContinueWith(callback) in the simplified code. A previous “piece” will end with a Task (which is to be awaited), when the task is done, it will callback the next “piece”. The state machine’s state works with the “case”s to ensure the code “piece”s executes one after another. Callback If we focus on the point of callback, the simplification  can go even further – the entire state machine can be completely purged, and we can just keep the code inside MoveNext(). Now MultiCallMethodAsync() becomes: internal static Task<int> MultiCallMethodAsync(int arg0, int arg1, int arg2, int arg3) { TaskCompletionSource<int> taskCompletionSource = new TaskCompletionSource<int>(); try { // Oringinal code begins. HelperMethods.Before(); MethodAsync(arg0, arg1).ContinueWith(await1 => { int resultOfAwait1 = await1.Result; HelperMethods.Continuation1(resultOfAwait1); MethodAsync(arg2, arg3).ContinueWith(await2 => { int resultOfAwait2 = await2.Result; HelperMethods.Continuation2(resultOfAwait2); int resultToReturn = resultOfAwait1 + resultOfAwait2; // Oringinal code ends. taskCompletionSource.SetResult(resultToReturn); }); }); } catch (Exception exception) { taskCompletionSource.SetException(exception); } return taskCompletionSource.Task; } Please compare with the original async / await code: HelperMethods.Before(); int resultOfAwait1 = await MethodAsync(arg0, arg1); HelperMethods.Continuation1(resultOfAwait1); int resultOfAwait2 = await MethodAsync(arg2, arg3); HelperMethods.Continuation2(resultOfAwait2); int resultToReturn = resultOfAwait1 + resultOfAwait2; return resultToReturn; Yeah that is the magic of C# async / await: Await is not to wait. In a await expression, a Task object will be return immediately so that execution is not blocked. The continuation code is compiled as that Task’s callback code. When that task is done, continuation code will execute. Please notice that many details inside the state machine are omitted for simplicity, like context caring, etc. If you want to have a detailed picture, please do check out the source code of AsyncTaskMethodBuilder and TaskAwaiter.

  Read the article

• Camera doesnt move on opengl qt

  - by hugo

  Here is my code, as my subject indicates i have implemented a camera but i couldnt make it move,Thanks in advance. #define PI_OVER_180 0.0174532925f define GL_CLAMP_TO_EDGE 0x812F include "metinalifeyyaz.h" include include include include include include include metinalifeyyaz::metinalifeyyaz(QWidget *parent) : QGLWidget(parent) { this->setFocusPolicy(Qt:: StrongFocus); time = QTime::currentTime(); timer = new QTimer(this); timer->setSingleShot(true); connect(timer, SIGNAL(timeout()), this, SLOT(updateGL())); xpos = yrot = zpos = 0; walkbias = walkbiasangle = lookupdown = 0.0f; keyUp = keyDown = keyLeft = keyRight = keyPageUp = keyPageDown = false; } void metinalifeyyaz::drawBall() { //glTranslatef(6,0,4); glutSolidSphere(0.10005,300,30); } metinalifeyyaz:: ~metinalifeyyaz(){ glDeleteTextures(1,texture); } void metinalifeyyaz::initializeGL(){ glShadeModel(GL_SMOOTH); glClearColor(1.0,1.0,1.0,0.5); glClearDepth(1.0f); glEnable(GL_DEPTH_TEST); glEnable(GL_TEXTURE_2D); glDepthFunc(GL_LEQUAL); glClearColor(1.0,1.0,1.0,1.0); glShadeModel(GL_SMOOTH); GLfloat mat_specular[]={1.0,1.0,1.0,1.0}; GLfloat mat_shininess []={30.0}; GLfloat light_position[]={1.0,1.0,1.0}; glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular); glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess); glLightfv(GL_LIGHT0, GL_POSITION, light_position); glEnable(GL_LIGHT0); glEnable(GL_LIGHTING); QImage img1 = convertToGLFormat(QImage(":/new/prefix1/halisaha2.bmp")); QImage img2 = convertToGLFormat(QImage(":/new/prefix1/white.bmp")); glGenTextures(2,texture); glBindTexture(GL_TEXTURE_2D, texture[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, img1.width(), img1.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img1.bits()); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glBindTexture(GL_TEXTURE_2D, texture[1]); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, img2.width(), img2.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img2.bits()); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); // Really nice perspective calculations } void metinalifeyyaz::resizeGL(int w, int h){ if(h==0) h=1; glViewport(0,0,w,h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45.0f, static_cast<GLfloat>(w)/h,0.1f,100.0f); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); } void metinalifeyyaz::paintGL(){ movePlayer(); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); GLfloat xtrans = -xpos; GLfloat ytrans = -walkbias - 0.50f; GLfloat ztrans = -zpos; GLfloat sceneroty = 360.0f - yrot; glLoadIdentity(); glRotatef(lookupdown, 1.0f, 0.0f, 0.0f); glRotatef(sceneroty, 0.0f, 1.0f, 0.0f); glTranslatef(xtrans, ytrans+50, ztrans-130); glLoadIdentity(); glTranslatef(1.0f,0.0f,-18.0f); glRotatef(45,1,0,0); drawScene(); int delay = time.msecsTo(QTime::currentTime()); if (delay == 0) delay = 1; time = QTime::currentTime(); timer->start(qMax(0,10 - delay)); } void metinalifeyyaz::movePlayer() { if (keyUp) { xpos -= sin(yrot * PI_OVER_180) * 0.5f; zpos -= cos(yrot * PI_OVER_180) * 0.5f; if (walkbiasangle >= 360.0f) walkbiasangle = 0.0f; else walkbiasangle += 7.0f; walkbias = sin(walkbiasangle * PI_OVER_180) / 10.0f; } else if (keyDown) { xpos += sin(yrot * PI_OVER_180)*0.5f; zpos += cos(yrot * PI_OVER_180)*0.5f ; if (walkbiasangle <= 7.0f) walkbiasangle = 360.0f; else walkbiasangle -= 7.0f; walkbias = sin(walkbiasangle * PI_OVER_180) / 10.0f; } if (keyLeft) yrot += 0.5f; else if (keyRight) yrot -= 0.5f; if (keyPageUp) lookupdown -= 0.5; else if (keyPageDown) lookupdown += 0.5; } void metinalifeyyaz::keyPressEvent(QKeyEvent *event) { switch (event->key()) { case Qt::Key_Escape: close(); break; case Qt::Key_F1: setWindowState(windowState() ^ Qt::WindowFullScreen); break; default: QGLWidget::keyPressEvent(event); case Qt::Key_PageUp: keyPageUp = true; break; case Qt::Key_PageDown: keyPageDown = true; break; case Qt::Key_Left: keyLeft = true; break; case Qt::Key_Right: keyRight = true; break; case Qt::Key_Up: keyUp = true; break; case Qt::Key_Down: keyDown = true; break; } } void metinalifeyyaz::changeEvent(QEvent *event) { switch (event->type()) { case QEvent::WindowStateChange: if (windowState() == Qt::WindowFullScreen) setCursor(Qt::BlankCursor); else unsetCursor(); break; default: break; } } void metinalifeyyaz::keyReleaseEvent(QKeyEvent *event) { switch (event->key()) { case Qt::Key_PageUp: keyPageUp = false; break; case Qt::Key_PageDown: keyPageDown = false; break; case Qt::Key_Left: keyLeft = false; break; case Qt::Key_Right: keyRight = false; break; case Qt::Key_Up: keyUp = false; break; case Qt::Key_Down: keyDown = false; break; default: QGLWidget::keyReleaseEvent(event); } } void metinalifeyyaz::drawScene(){ glBegin(GL_QUADS); glNormal3f(0.0f,0.0f,1.0f); // glColor3f(0,0,1); //back glVertex3f(-6,0,-4); glVertex3f(-6,-0.5,-4); glVertex3f(6,-0.5,-4); glVertex3f(6,0,-4); glEnd(); glBegin(GL_QUADS); glNormal3f(0.0f,0.0f,-1.0f); //front glVertex3f(6,0,4); glVertex3f(6,-0.5,4); glVertex3f(-6,-0.5,4); glVertex3f(-6,0,4); glEnd(); glBegin(GL_QUADS); glNormal3f(-1.0f,0.0f,0.0f); // glColor3f(0,0,1); //left glVertex3f(-6,0,4); glVertex3f(-6,-0.5,4); glVertex3f(-6,-0.5,-4); glVertex3f(-6,0,-4); glEnd(); glBegin(GL_QUADS); glNormal3f(1.0f,0.0f,0.0f); // glColor3f(0,0,1); //right glVertex3f(6,0,-4); glVertex3f(6,-0.5,-4); glVertex3f(6,-0.5,4); glVertex3f(6,0,4); glEnd(); glBindTexture(GL_TEXTURE_2D, texture[0]); glBegin(GL_QUADS); glNormal3f(0.0f,1.0f,0.0f);//top glTexCoord2f(1.0f,0.0f); glVertex3f(6,0,-4); glTexCoord2f(1.0f,1.0f); glVertex3f(6,0,4); glTexCoord2f(0.0f,1.0f); glVertex3f(-6,0,4); glTexCoord2f(0.0f,0.0f); glVertex3f(-6,0,-4); glEnd(); glBegin(GL_QUADS); glNormal3f(0.0f,-1.0f,0.0f); //glColor3f(0,0,1); //bottom glVertex3f(6,-0.5,-4); glVertex3f(6,-0.5,4); glVertex3f(-6,-0.5,4); glVertex3f(-6,-0.5,-4); glEnd(); // glPushMatrix(); glBindTexture(GL_TEXTURE_2D, texture[1]); glBegin(GL_QUADS); glNormal3f(1.0f,0.0f,0.0f); glTexCoord2f(1.0f,0.0f); //right far goal post front face glVertex3f(5,0.5,-0.95); glTexCoord2f(1.0f,1.0f); glVertex3f(5,0,-0.95); glTexCoord2f(0.0f,1.0f); glVertex3f(5,0,-1); glTexCoord2f(0.0f,0.0f); glVertex3f(5, 0.5, -1); glColor3f(1,1,1); //right far goal post back face glVertex3f(5.05,0.5,-0.95); glVertex3f(5.05,0,-0.95); glVertex3f(5.05,0,-1); glVertex3f(5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post left face glVertex3f(5,0.5,-1); glVertex3f(5,0,-1); glVertex3f(5.05,0,-1); glVertex3f(5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post right face glVertex3f(5.05,0.5,-0.95); glVertex3f(5.05,0,-0.95); glVertex3f(5,0,-0.95); glVertex3f(5, 0.5, -0.95); glColor3f(1,1,1); //right near goal post front face glVertex3f(5,0.5,0.95); glVertex3f(5,0,0.95); glVertex3f(5,0,1); glVertex3f(5,0.5, 1); glColor3f(1,1,1); //right near goal post back face glVertex3f(5.05,0.5,0.95); glVertex3f(5.05,0,0.95); glVertex3f(5.05,0,1); glVertex3f(5.05,0.5, 1); glColor3f(1,1,1); //right near goal post left face glVertex3f(5,0.5,1); glVertex3f(5,0,1); glVertex3f(5.05,0,1); glVertex3f(5.05,0.5, 1); glColor3f(1,1,1); //right near goal post right face glVertex3f(5.05,0.5,0.95); glVertex3f(5.05,0,0.95); glVertex3f(5,0,0.95); glVertex3f(5,0.5, 0.95); glColor3f(1,1,1); //right crossbar front face glVertex3f(5,0.55,-1); glVertex3f(5,0.55,1); glVertex3f(5,0.5,1); glVertex3f(5,0.5,-1); glColor3f(1,1,1); //right crossbar back face glVertex3f(5.05,0.55,-1); glVertex3f(5.05,0.55,1); glVertex3f(5.05,0.5,1); glVertex3f(5.05,0.5,-1); glColor3f(1,1,1); //right crossbar bottom face glVertex3f(5.05,0.5,-1); glVertex3f(5.05,0.5,1); glVertex3f(5,0.5,1); glVertex3f(5,0.5,-1); glColor3f(1,1,1); //right crossbar top face glVertex3f(5.05,0.55,-1); glVertex3f(5.05,0.55,1); glVertex3f(5,0.55,1); glVertex3f(5,0.55,-1); glColor3f(1,1,1); //left far goal post front face glVertex3f(-5,0.5,-0.95); glVertex3f(-5,0,-0.95); glVertex3f(-5,0,-1); glVertex3f(-5, 0.5, -1); glColor3f(1,1,1); //right far goal post back face glVertex3f(-5.05,0.5,-0.95); glVertex3f(-5.05,0,-0.95); glVertex3f(-5.05,0,-1); glVertex3f(-5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post left face glVertex3f(-5,0.5,-1); glVertex3f(-5,0,-1); glVertex3f(-5.05,0,-1); glVertex3f(-5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post right face glVertex3f(-5.05,0.5,-0.95); glVertex3f(-5.05,0,-0.95); glVertex3f(-5,0,-0.95); glVertex3f(-5, 0.5, -0.95); glColor3f(1,1,1); //left near goal post front face glVertex3f(-5,0.5,0.95); glVertex3f(-5,0,0.95); glVertex3f(-5,0,1); glVertex3f(-5,0.5, 1); glColor3f(1,1,1); //right near goal post back face glVertex3f(-5.05,0.5,0.95); glVertex3f(-5.05,0,0.95); glVertex3f(-5.05,0,1); glVertex3f(-5.05,0.5, 1); glColor3f(1,1,1); //right near goal post left face glVertex3f(-5,0.5,1); glVertex3f(-5,0,1); glVertex3f(-5.05,0,1); glVertex3f(-5.05,0.5, 1); glColor3f(1,1,1); //right near goal post right face glVertex3f(-5.05,0.5,0.95); glVertex3f(-5.05,0,0.95); glVertex3f(-5,0,0.95); glVertex3f(-5,0.5, 0.95); glColor3f(1,1,1); //left crossbar front face glVertex3f(-5,0.55,-1); glVertex3f(-5,0.55,1); glVertex3f(-5,0.5,1); glVertex3f(-5,0.5,-1); glColor3f(1,1,1); //right crossbar back face glVertex3f(-5.05,0.55,-1); glVertex3f(-5.05,0.55,1); glVertex3f(-5.05,0.5,1); glVertex3f(-5.05,0.5,-1); glColor3f(1,1,1); //right crossbar bottom face glVertex3f(-5.05,0.5,-1); glVertex3f(-5.05,0.5,1); glVertex3f(-5,0.5,1); glVertex3f(-5,0.5,-1); glColor3f(1,1,1); //right crossbar top face glVertex3f(-5.05,0.55,-1); glVertex3f(-5.05,0.55,1); glVertex3f(-5,0.55,1); glVertex3f(-5,0.55,-1); glEnd(); // glPopMatrix(); // glPushMatrix(); // glTranslatef(0,0,0); // glutSolidSphere(0.10005,500,30); // glPopMatrix(); }

  Read the article

• Remove box2d bodies after collision deduction android?

  - by jubin

  Can any one explain me how to destroy box2d body when collide i have tried but my application crashed.First i have checked al collisions then add all the bodies in array who i want to destroy.I am trying to learning this tutorial My all the bodies are falling i want these bodies should destroy when these bodies will collide my actor monkey but when it collide it destroy but my aplication crashed.I have googled and from google i got the application crash reasons we should not destroy body in step funtion but i am removing body in the last of tick method. could any one help me or provide me code aur check my code why i am getting this prblem or how can i destroy box2d bodies. This is my code what i am doing. Please could any one check my code and tell me what is i am doing wrong for removing bodies. The code is for multiple box2d objects falling on my actor monkey it should be destroy when it will fall on the monkey.It is destroing but my application crahes. static class Box2DLayer extends CCLayer { protected static final float PTM_RATIO = 32.0f; protected static final float WALK_FACTOR = 3.0f; protected static final float MAX_WALK_IMPULSE = 0.2f; protected static final float ANIM_SPEED = 0.3f; int isLeft=0; String dir=""; int x =0; float direction; CCColorLayer objectHint; // protected static final float PTM_RATIO = 32.0f; protected World _world; protected static Body spriteBody; CGSize winSize = CCDirector.sharedDirector().winSize(); private static int count = 200; protected static Body monkey_body; private static Body bodies; CCSprite monkey; float animDelay; int animPhase; CCSpriteSheet danceSheet = CCSpriteSheet.spriteSheet("phases.png"); CCSprite _block; List<Body> toDestroy = new ArrayList<Body>(); //CCSpriteSheet _spriteSheet; private static MyContactListener _contactListener = new MyContactListener(); public Box2DLayer() { this.setIsAccelerometerEnabled(true); CCSprite bg = CCSprite.sprite("jungle.png"); addChild(bg,0); bg.setAnchorPoint(0,0); bg.setPosition(0,0); CGSize s = CCDirector.sharedDirector().winSize(); // Use scaled width and height so that our boundaries always match the current screen float scaledWidth = s.width/PTM_RATIO; float scaledHeight = s.height/PTM_RATIO; Vector2 gravity = new Vector2(0.0f, -30.0f); boolean doSleep = false; _world = new World(gravity, doSleep); // Create edges around the entire screen // Define the ground body. BodyDef bxGroundBodyDef = new BodyDef(); bxGroundBodyDef.position.set(0.0f, 0.0f); // The body is also added to the world. Body groundBody = _world.createBody(bxGroundBodyDef); // Register our contact listener // Define the ground box shape. PolygonShape groundBox = new PolygonShape(); Vector2 bottomLeft = new Vector2(0f,0f); Vector2 topLeft = new Vector2(0f,scaledHeight); Vector2 topRight = new Vector2(scaledWidth,scaledHeight); Vector2 bottomRight = new Vector2(scaledWidth,0f); // bottom groundBox.setAsEdge(bottomLeft, bottomRight); groundBody.createFixture(groundBox,0); // top groundBox.setAsEdge(topLeft, topRight); groundBody.createFixture(groundBox,0); // left groundBox.setAsEdge(topLeft, bottomLeft); groundBody.createFixture(groundBox,0); // right groundBox.setAsEdge(topRight, bottomRight); groundBody.createFixture(groundBox,0); CCSprite floorbg = CCSprite.sprite("grassbehind.png"); addChild(floorbg,1); floorbg.setAnchorPoint(0,0); floorbg.setPosition(0,0); CCSprite floorfront = CCSprite.sprite("grassfront.png"); floorfront.setTag(2); this.addBoxBodyForSprite(floorfront); addChild(floorfront,3); floorfront.setAnchorPoint(0,0); floorfront.setPosition(0,0); addChild(danceSheet); //CCSprite monkey = CCSprite.sprite(danceSheet, CGRect.make(0, 0, 48, 73)); //addChild(danceSprite); monkey = CCSprite.sprite("arms_up.png"); monkey.setTag(2); monkey.setPosition(200,100); BodyDef spriteBodyDef = new BodyDef(); spriteBodyDef.type = BodyType.DynamicBody; spriteBodyDef.bullet=true; spriteBodyDef.position.set(200 / PTM_RATIO, 300 / PTM_RATIO); monkey_body = _world.createBody(spriteBodyDef); monkey_body.setUserData(monkey); PolygonShape spriteShape = new PolygonShape(); spriteShape.setAsBox(monkey.getContentSize().width/PTM_RATIO/2, monkey.getContentSize().height/PTM_RATIO/2); FixtureDef spriteShapeDef = new FixtureDef(); spriteShapeDef.shape = spriteShape; spriteShapeDef.density = 2.0f; spriteShapeDef.friction = 0.70f; spriteShapeDef.restitution = 0.0f; monkey_body.createFixture(spriteShapeDef); //Vector2 force = new Vector2(10, 10); //monkey_body.applyLinearImpulse(force, spriteBodyDef.position); addChild(monkey,10000); this.schedule(tickCallback); this.schedule(createobjects, 2.0f); objectHint = CCColorLayer.node(ccColor4B.ccc4(255,0,0,128), 200f, 100f); addChild(objectHint, 15000); objectHint.setVisible(false); _world.setContactListener(_contactListener); } private UpdateCallback tickCallback = new UpdateCallback() { public void update(float d) { tick(d); } }; private UpdateCallback createobjects = new UpdateCallback() { public void update(float d) { secondUpdate(d); } }; private void secondUpdate(float dt) { this.addNewSprite(); } public void addBoxBodyForSprite(CCSprite sprite) { BodyDef spriteBodyDef = new BodyDef(); spriteBodyDef.type = BodyType.StaticBody; //spriteBodyDef.bullet=true; spriteBodyDef.position.set(sprite.getPosition().x / PTM_RATIO, sprite.getPosition().y / PTM_RATIO); spriteBody = _world.createBody(spriteBodyDef); spriteBody.setUserData(sprite); Vector2 verts[] = { new Vector2(-11.8f / PTM_RATIO, -24.5f / PTM_RATIO), new Vector2(11.7f / PTM_RATIO, -24.0f / PTM_RATIO), new Vector2(29.2f / PTM_RATIO, -14.0f / PTM_RATIO), new Vector2(28.7f / PTM_RATIO, -0.7f / PTM_RATIO), new Vector2(8.0f / PTM_RATIO, 18.2f / PTM_RATIO), new Vector2(-29.0f / PTM_RATIO, 18.7f / PTM_RATIO), new Vector2(-26.3f / PTM_RATIO, -12.2f / PTM_RATIO) }; PolygonShape spriteShape = new PolygonShape(); spriteShape.set(verts); //spriteShape.setAsBox(sprite.getContentSize().width/PTM_RATIO/2, //sprite.getContentSize().height/PTM_RATIO/2); FixtureDef spriteShapeDef = new FixtureDef(); spriteShapeDef.shape = spriteShape; spriteShapeDef.density = 2.0f; spriteShapeDef.friction = 0.70f; spriteShapeDef.restitution = 0.0f; spriteShapeDef.isSensor=true; spriteBody.createFixture(spriteShapeDef); } public void addNewSprite() { count=0; Random rand = new Random(); int Number = rand.nextInt(10); switch(Number) { case 0: _block = CCSprite.sprite("banana.png"); break; case 1: _block = CCSprite.sprite("backpack.png");break; case 2: _block = CCSprite.sprite("statue.png");break; case 3: _block = CCSprite.sprite("pineapple.png");break; case 4: _block = CCSprite.sprite("bananabunch.png");break; case 5: _block = CCSprite.sprite("hat.png");break; case 6: _block = CCSprite.sprite("canteen.png");break; case 7: _block = CCSprite.sprite("banana.png");break; case 8: _block = CCSprite.sprite("statue.png");break; case 9: _block = CCSprite.sprite("hat.png");break; } int padding=20; //_block.setPosition(CGPoint.make(100, 100)); // Determine where to spawn the target along the Y axis CGSize winSize = CCDirector.sharedDirector().displaySize(); int minY = (int)(_block.getContentSize().width / 2.0f); int maxY = (int)(winSize.width - _block.getContentSize().width / 2.0f); int rangeY = maxY - minY; int actualY = rand.nextInt(rangeY) + minY; // Create block and add it to the layer float xOffset = padding+_block.getContentSize().width/2+((_block.getContentSize().width+padding)*count); _block.setPosition(CGPoint.make(actualY, 750)); _block.setTag(1); float w = _block.getContentSize().width; objectHint.setVisible(true); objectHint.changeWidth(w); objectHint.setPosition(actualY-w/2, 460); this.addChild(_block,10000); // Create ball body and shape BodyDef ballBodyDef1 = new BodyDef(); ballBodyDef1.type = BodyType.DynamicBody; ballBodyDef1.position.set(actualY/PTM_RATIO, 480/PTM_RATIO); bodies = _world.createBody(ballBodyDef1); bodies.setUserData(_block); PolygonShape circle1 = new PolygonShape(); Vector2 verts[] = { new Vector2(-11.8f / PTM_RATIO, -24.5f / PTM_RATIO), new Vector2(11.7f / PTM_RATIO, -24.0f / PTM_RATIO), new Vector2(29.2f / PTM_RATIO, -14.0f / PTM_RATIO), new Vector2(28.7f / PTM_RATIO, -0.7f / PTM_RATIO), new Vector2(8.0f / PTM_RATIO, 18.2f / PTM_RATIO), new Vector2(-29.0f / PTM_RATIO, 18.7f / PTM_RATIO), new Vector2(-26.3f / PTM_RATIO, -12.2f / PTM_RATIO) }; circle1.set(verts); FixtureDef ballShapeDef1 = new FixtureDef(); ballShapeDef1.shape = circle1; ballShapeDef1.density = 10.0f; ballShapeDef1.friction = 0.0f; ballShapeDef1.restitution = 0.1f; bodies.createFixture(ballShapeDef1); count++; //Remove(); } @Override public void ccAccelerometerChanged(float accelX, float accelY, float accelZ) { //Apply the directional impulse /*float impulse = monkey_body.getMass()*accelY*WALK_FACTOR; Vector2 force = new Vector2(impulse, 0); monkey_body.applyLinearImpulse(force, monkey_body.getWorldCenter());*/ walk(accelY); //Remove(); } private void walk(float accelY) { // TODO Auto-generated method stub direction = accelY; } private void Remove() { for (Iterator<MyContact> it1 = _contactListener.mContacts.iterator(); it1.hasNext();) { MyContact contact = it1.next(); Body bodyA = contact.fixtureA.getBody(); Body bodyB = contact.fixtureB.getBody(); // See if there's any user data attached to the Box2D body // There should be, since we set it in addBoxBodyForSprite if (bodyA.getUserData() != null && bodyB.getUserData() != null) { CCSprite spriteA = (CCSprite) bodyA.getUserData(); CCSprite spriteB = (CCSprite) bodyB.getUserData(); // Is sprite A a cat and sprite B a car? If so, push the cat // on a list to be destroyed... if (spriteA.getTag() == 1 && spriteB.getTag() == 2) { //Log.v("dsfds", "dsfsd"+bodyA); //_world.destroyBody(bodyA); // removeChild(spriteA, true); toDestroy.add(bodyA); } // Is sprite A a car and sprite B a cat? If so, push the cat // on a list to be destroyed... else if (spriteA.getTag() == 2 && spriteB.getTag() == 1) { //Log.v("dsfds", "dsfsd"+bodyB); toDestroy.add(bodyB); } } } // Loop through all of the box2d bodies we want to destroy... for (Iterator<Body> it1 = toDestroy.iterator(); it1.hasNext();) { Body body = it1.next(); // See if there's any user data attached to the Box2D body // There should be, since we set it in addBoxBodyForSprite if (body.getUserData() != null) { // We know that the user data is a sprite since we set // it that way, so cast it... CCSprite sprite = (CCSprite) body.getUserData(); // Remove the sprite from the scene _world.destroyBody(body); removeChild(sprite, true); } // Destroy the Box2D body as well // _contactListener.mContacts.remove(0); } } public synchronized void tick(float delta) { synchronized (_world) { _world.step(delta, 8, 3); //_world.clearForces(); //addNewSprite(); } CCAnimation danceAnimation = CCAnimation.animation("dance", 1.0f); // Iterate over the bodies in the physics world Iterator<Body> it = _world.getBodies(); while(it.hasNext()) { Body b = it.next(); Object userData = b.getUserData(); if (userData != null && userData instanceof CCSprite) { //Synchronize the Sprites position and rotation with the corresponding body CCSprite sprite = (CCSprite)userData; if(sprite.getTag()==1) { //b.applyLinearImpulse(force, pos); sprite.setPosition(b.getPosition().x * PTM_RATIO, b.getPosition().y * PTM_RATIO); sprite.setRotation(-1.0f * ccMacros.CC_RADIANS_TO_DEGREES(b.getAngle())); } else { //Apply the directional impulse float impulse = monkey_body.getMass()*direction*WALK_FACTOR; Vector2 force = new Vector2(impulse, 0); b.applyLinearImpulse(force, b.getWorldCenter()); sprite.setPosition(b.getPosition().x * PTM_RATIO, b.getPosition().y * PTM_RATIO); animDelay -= 1.0f/60.0f; if(animDelay <= 0) { animDelay = ANIM_SPEED; animPhase++; if(animPhase > 2) { animPhase = 1; } } if(direction < 0 ) { isLeft=1; } else { isLeft=0; } if(isLeft==1) { dir = "left"; } else { dir = "right"; } float standingLimit = (float) 0.1f; float vX = monkey_body.getLinearVelocity().x; if((vX > -standingLimit)&& (vX < standingLimit)) { // Log.v("sasd", "standing"); } else { } } } } Remove(); } } Sorry for my english. Thanks in advance.

  Read the article

• Camera doesn't move

  - by hugo

  Here is my code, as my subject indicates i have implemented a camera but I couldn't make it move. #define PI_OVER_180 0.0174532925f #define GL_CLAMP_TO_EDGE 0x812F #include "metinalifeyyaz.h" #include <GL/glu.h> #include <GL/glut.h> #include <QTimer> #include <cmath> #include <QKeyEvent> #include <QWidget> #include <QDebug> metinalifeyyaz::metinalifeyyaz(QWidget *parent) : QGLWidget(parent) { this->setFocusPolicy(Qt:: StrongFocus); time = QTime::currentTime(); timer = new QTimer(this); timer->setSingleShot(true); connect(timer, SIGNAL(timeout()), this, SLOT(updateGL())); xpos = yrot = zpos = 0; walkbias = walkbiasangle = lookupdown = 0.0f; keyUp = keyDown = keyLeft = keyRight = keyPageUp = keyPageDown = false; } void metinalifeyyaz::drawBall() { //glTranslatef(6,0,4); glutSolidSphere(0.10005,300,30); } metinalifeyyaz:: ~metinalifeyyaz(){ glDeleteTextures(1,texture); } void metinalifeyyaz::initializeGL(){ glShadeModel(GL_SMOOTH); glClearColor(1.0,1.0,1.0,0.5); glClearDepth(1.0f); glEnable(GL_DEPTH_TEST); glEnable(GL_TEXTURE_2D); glDepthFunc(GL_LEQUAL); glClearColor(1.0,1.0,1.0,1.0); glShadeModel(GL_SMOOTH); GLfloat mat_specular[]={1.0,1.0,1.0,1.0}; GLfloat mat_shininess []={30.0}; GLfloat light_position[]={1.0,1.0,1.0}; glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular); glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess); glLightfv(GL_LIGHT0, GL_POSITION, light_position); glEnable(GL_LIGHT0); glEnable(GL_LIGHTING); QImage img1 = convertToGLFormat(QImage(":/new/prefix1/halisaha2.bmp")); QImage img2 = convertToGLFormat(QImage(":/new/prefix1/white.bmp")); glGenTextures(2,texture); glBindTexture(GL_TEXTURE_2D, texture[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, img1.width(), img1.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img1.bits()); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glBindTexture(GL_TEXTURE_2D, texture[1]); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, img2.width(), img2.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img2.bits()); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); // Really nice perspective calculations } void metinalifeyyaz::resizeGL(int w, int h){ if(h==0) h=1; glViewport(0,0,w,h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45.0f, static_cast<GLfloat>(w)/h,0.1f,100.0f); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); } void metinalifeyyaz::paintGL(){ movePlayer(); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); GLfloat xtrans = -xpos; GLfloat ytrans = -walkbias - 0.50f; GLfloat ztrans = -zpos; GLfloat sceneroty = 360.0f - yrot; glLoadIdentity(); glRotatef(lookupdown, 1.0f, 0.0f, 0.0f); glRotatef(sceneroty, 0.0f, 1.0f, 0.0f); glTranslatef(xtrans, ytrans+50, ztrans-130); glLoadIdentity(); glTranslatef(1.0f,0.0f,-18.0f); glRotatef(45,1,0,0); drawScene(); int delay = time.msecsTo(QTime::currentTime()); if (delay == 0) delay = 1; time = QTime::currentTime(); timer->start(qMax(0,10 - delay)); } void metinalifeyyaz::movePlayer() { if (keyUp) { xpos -= sin(yrot * PI_OVER_180) * 0.5f; zpos -= cos(yrot * PI_OVER_180) * 0.5f; if (walkbiasangle >= 360.0f) walkbiasangle = 0.0f; else walkbiasangle += 7.0f; walkbias = sin(walkbiasangle * PI_OVER_180) / 10.0f; } else if (keyDown) { xpos += sin(yrot * PI_OVER_180)*0.5f; zpos += cos(yrot * PI_OVER_180)*0.5f ; if (walkbiasangle <= 7.0f) walkbiasangle = 360.0f; else walkbiasangle -= 7.0f; walkbias = sin(walkbiasangle * PI_OVER_180) / 10.0f; } if (keyLeft) yrot += 0.5f; else if (keyRight) yrot -= 0.5f; if (keyPageUp) lookupdown -= 0.5; else if (keyPageDown) lookupdown += 0.5; } void metinalifeyyaz::keyPressEvent(QKeyEvent *event) { switch (event->key()) { case Qt::Key_Escape: close(); break; case Qt::Key_F1: setWindowState(windowState() ^ Qt::WindowFullScreen); break; default: QGLWidget::keyPressEvent(event); case Qt::Key_PageUp: keyPageUp = true; break; case Qt::Key_PageDown: keyPageDown = true; break; case Qt::Key_Left: keyLeft = true; break; case Qt::Key_Right: keyRight = true; break; case Qt::Key_Up: keyUp = true; break; case Qt::Key_Down: keyDown = true; break; } } void metinalifeyyaz::changeEvent(QEvent *event) { switch (event->type()) { case QEvent::WindowStateChange: if (windowState() == Qt::WindowFullScreen) setCursor(Qt::BlankCursor); else unsetCursor(); break; default: break; } } void metinalifeyyaz::keyReleaseEvent(QKeyEvent *event) { switch (event->key()) { case Qt::Key_PageUp: keyPageUp = false; break; case Qt::Key_PageDown: keyPageDown = false; break; case Qt::Key_Left: keyLeft = false; break; case Qt::Key_Right: keyRight = false; break; case Qt::Key_Up: keyUp = false; break; case Qt::Key_Down: keyDown = false; break; default: QGLWidget::keyReleaseEvent(event); } } void metinalifeyyaz::drawScene(){ glBegin(GL_QUADS); glNormal3f(0.0f,0.0f,1.0f); // glColor3f(0,0,1); //back glVertex3f(-6,0,-4); glVertex3f(-6,-0.5,-4); glVertex3f(6,-0.5,-4); glVertex3f(6,0,-4); glEnd(); glBegin(GL_QUADS); glNormal3f(0.0f,0.0f,-1.0f); //front glVertex3f(6,0,4); glVertex3f(6,-0.5,4); glVertex3f(-6,-0.5,4); glVertex3f(-6,0,4); glEnd(); glBegin(GL_QUADS); glNormal3f(-1.0f,0.0f,0.0f); // glColor3f(0,0,1); //left glVertex3f(-6,0,4); glVertex3f(-6,-0.5,4); glVertex3f(-6,-0.5,-4); glVertex3f(-6,0,-4); glEnd(); glBegin(GL_QUADS); glNormal3f(1.0f,0.0f,0.0f); // glColor3f(0,0,1); //right glVertex3f(6,0,-4); glVertex3f(6,-0.5,-4); glVertex3f(6,-0.5,4); glVertex3f(6,0,4); glEnd(); glBindTexture(GL_TEXTURE_2D, texture[0]); glBegin(GL_QUADS); glNormal3f(0.0f,1.0f,0.0f);//top glTexCoord2f(1.0f,0.0f); glVertex3f(6,0,-4); glTexCoord2f(1.0f,1.0f); glVertex3f(6,0,4); glTexCoord2f(0.0f,1.0f); glVertex3f(-6,0,4); glTexCoord2f(0.0f,0.0f); glVertex3f(-6,0,-4); glEnd(); glBegin(GL_QUADS); glNormal3f(0.0f,-1.0f,0.0f); //glColor3f(0,0,1); //bottom glVertex3f(6,-0.5,-4); glVertex3f(6,-0.5,4); glVertex3f(-6,-0.5,4); glVertex3f(-6,-0.5,-4); glEnd(); // glPushMatrix(); glBindTexture(GL_TEXTURE_2D, texture[1]); glBegin(GL_QUADS); glNormal3f(1.0f,0.0f,0.0f); glTexCoord2f(1.0f,0.0f); //right far goal post front face glVertex3f(5,0.5,-0.95); glTexCoord2f(1.0f,1.0f); glVertex3f(5,0,-0.95); glTexCoord2f(0.0f,1.0f); glVertex3f(5,0,-1); glTexCoord2f(0.0f,0.0f); glVertex3f(5, 0.5, -1); glColor3f(1,1,1); //right far goal post back face glVertex3f(5.05,0.5,-0.95); glVertex3f(5.05,0,-0.95); glVertex3f(5.05,0,-1); glVertex3f(5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post left face glVertex3f(5,0.5,-1); glVertex3f(5,0,-1); glVertex3f(5.05,0,-1); glVertex3f(5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post right face glVertex3f(5.05,0.5,-0.95); glVertex3f(5.05,0,-0.95); glVertex3f(5,0,-0.95); glVertex3f(5, 0.5, -0.95); glColor3f(1,1,1); //right near goal post front face glVertex3f(5,0.5,0.95); glVertex3f(5,0,0.95); glVertex3f(5,0,1); glVertex3f(5,0.5, 1); glColor3f(1,1,1); //right near goal post back face glVertex3f(5.05,0.5,0.95); glVertex3f(5.05,0,0.95); glVertex3f(5.05,0,1); glVertex3f(5.05,0.5, 1); glColor3f(1,1,1); //right near goal post left face glVertex3f(5,0.5,1); glVertex3f(5,0,1); glVertex3f(5.05,0,1); glVertex3f(5.05,0.5, 1); glColor3f(1,1,1); //right near goal post right face glVertex3f(5.05,0.5,0.95); glVertex3f(5.05,0,0.95); glVertex3f(5,0,0.95); glVertex3f(5,0.5, 0.95); glColor3f(1,1,1); //right crossbar front face glVertex3f(5,0.55,-1); glVertex3f(5,0.55,1); glVertex3f(5,0.5,1); glVertex3f(5,0.5,-1); glColor3f(1,1,1); //right crossbar back face glVertex3f(5.05,0.55,-1); glVertex3f(5.05,0.55,1); glVertex3f(5.05,0.5,1); glVertex3f(5.05,0.5,-1); glColor3f(1,1,1); //right crossbar bottom face glVertex3f(5.05,0.5,-1); glVertex3f(5.05,0.5,1); glVertex3f(5,0.5,1); glVertex3f(5,0.5,-1); glColor3f(1,1,1); //right crossbar top face glVertex3f(5.05,0.55,-1); glVertex3f(5.05,0.55,1); glVertex3f(5,0.55,1); glVertex3f(5,0.55,-1); glColor3f(1,1,1); //left far goal post front face glVertex3f(-5,0.5,-0.95); glVertex3f(-5,0,-0.95); glVertex3f(-5,0,-1); glVertex3f(-5, 0.5, -1); glColor3f(1,1,1); //right far goal post back face glVertex3f(-5.05,0.5,-0.95); glVertex3f(-5.05,0,-0.95); glVertex3f(-5.05,0,-1); glVertex3f(-5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post left face glVertex3f(-5,0.5,-1); glVertex3f(-5,0,-1); glVertex3f(-5.05,0,-1); glVertex3f(-5.05, 0.5, -1); glColor3f(1,1,1); //right far goal post right face glVertex3f(-5.05,0.5,-0.95); glVertex3f(-5.05,0,-0.95); glVertex3f(-5,0,-0.95); glVertex3f(-5, 0.5, -0.95); glColor3f(1,1,1); //left near goal post front face glVertex3f(-5,0.5,0.95); glVertex3f(-5,0,0.95); glVertex3f(-5,0,1); glVertex3f(-5,0.5, 1); glColor3f(1,1,1); //right near goal post back face glVertex3f(-5.05,0.5,0.95); glVertex3f(-5.05,0,0.95); glVertex3f(-5.05,0,1); glVertex3f(-5.05,0.5, 1); glColor3f(1,1,1); //right near goal post left face glVertex3f(-5,0.5,1); glVertex3f(-5,0,1); glVertex3f(-5.05,0,1); glVertex3f(-5.05,0.5, 1); glColor3f(1,1,1); //right near goal post right face glVertex3f(-5.05,0.5,0.95); glVertex3f(-5.05,0,0.95); glVertex3f(-5,0,0.95); glVertex3f(-5,0.5, 0.95); glColor3f(1,1,1); //left crossbar front face glVertex3f(-5,0.55,-1); glVertex3f(-5,0.55,1); glVertex3f(-5,0.5,1); glVertex3f(-5,0.5,-1); glColor3f(1,1,1); //right crossbar back face glVertex3f(-5.05,0.55,-1); glVertex3f(-5.05,0.55,1); glVertex3f(-5.05,0.5,1); glVertex3f(-5.05,0.5,-1); glColor3f(1,1,1); //right crossbar bottom face glVertex3f(-5.05,0.5,-1); glVertex3f(-5.05,0.5,1); glVertex3f(-5,0.5,1); glVertex3f(-5,0.5,-1); glColor3f(1,1,1); //right crossbar top face glVertex3f(-5.05,0.55,-1); glVertex3f(-5.05,0.55,1); glVertex3f(-5,0.55,1); glVertex3f(-5,0.55,-1); glEnd(); // glPopMatrix(); // glPushMatrix(); // glTranslatef(0,0,0); // glutSolidSphere(0.10005,500,30); // glPopMatrix(); }

  Read the article

• Implementing a generic repository for WCF data services

  - by cibrax

  The repository implementation I am going to discuss here is not exactly what someone would call repository in terms of DDD, but it is an abstraction layer that becomes handy at the moment of unit testing the code around this repository. In other words, you can easily create a mock to replace the real repository implementation. The WCF Data Services update for .NET 3.5 introduced a nice feature to support two way data bindings, which is very helpful for developing WPF or Silverlight based application but also for implementing the repository I am going to talk about. As part of this feature, the WCF Data Services Client library introduced a new collection DataServiceCollection<T> that implements INotifyPropertyChanged to notify the data context (DataServiceContext) about any change in the association links. This means that it is not longer necessary to manually set or remove the links in the data context when an item is added or removed from a collection. Before having this new collection, you basically used the following code to add a new item to a collection. Order order = new Order {   Name = "Foo" }; OrderItem item = new OrderItem {   Name = "bar",   UnitPrice = 10,   Qty = 1 }; var context = new OrderContext(); context.AddToOrders(order); context.AddToOrderItems(item); context.SetLink(item, "Order", order); context.SaveChanges(); Now, thanks to this new collection, everything is much simpler and similar to what you have in other ORMs like Entity Framework or L2S. Order order = new Order {   Name = "Foo" }; OrderItem item = new OrderItem {   Name = "bar",   UnitPrice = 10,   Qty = 1 }; order.Items.Add(item); var context = new OrderContext(); context.AddToOrders(order); context.SaveChanges(); In order to use this new feature, you first need to enable V2 in the data service, and then use some specific arguments in the datasvcutil tool (You can find more information about this new feature and how to use it in this post). DataSvcUtil /uri:"http://localhost:3655/MyDataService.svc/" /out:Reference.cs /dataservicecollection /version:2.0 Once you use those two arguments, the generated proxy classes will use DataServiceCollection<T> rather than a simple ObjectCollection<T>, which was the default collection in V1. There are some aspects that you need to know to use this feature correctly. 1. All the entities retrieved directly from the data context with a query track the changes and report those to the data context automatically. 2. A entity created with “new” does not track any change in the properties or associations. In order to enable change tracking in this entity, you need to do the following trick. public Order CreateOrder() {   var collection = new DataServiceCollection<Order>(this.context);   var order = new Order();   collection.Add(order);   return order; } You basically need to create a collection, and add the entity to that collection with the “Add” method to enable change tracking on that entity. 3. If you need to attach an existing entity (For example, if you created the entity with the “new” operator rather than retrieving it from the data context with a query) to a data context for tracking changes, you can use the “Load” method in the DataServiceCollection. var order = new Order {   Id = 1 }; var collection = new DataServiceCollection<Order>(this.context); collection.Load(order); In this case, the order with Id = 1 must exist on the data source exposed by the Data service. Otherwise, you will get an error because the entity did not exist. These cool extensions methods discussed by Stuart Leeks in this post to replace all the magic strings in the “Expand” operation with Expression Trees represent another feature I am going to use to implement this generic repository. Thanks to these extension methods, you could replace the following query with magic strings by a piece of code that only uses expressions. Magic strings, var customers = dataContext.Customers .Expand("Orders")         .Expand("Orders/Items") Expressions, var customers = dataContext.Customers .Expand(c => c.Orders.SubExpand(o => o.Items)) That query basically returns all the customers with their orders and order items. Ok, now that we have the automatic change tracking support and the expression support for explicitly loading entity associations, we are ready to create the repository. The interface for this repository looks like this,public interface IRepository { T Create<T>() where T : new(); void Update<T>(T entity); void Delete<T>(T entity); IQueryable<T> RetrieveAll<T>(params Expression<Func<T, object>>[] eagerProperties); IQueryable<T> Retrieve<T>(Expression<Func<T, bool>> predicate, params Expression<Func<T, object>>[] eagerProperties); void Attach<T>(T entity); void SaveChanges(); } The Retrieve and RetrieveAll methods are used to execute queries against the data service context. While both methods receive an array of expressions to load associations explicitly, only the Retrieve method receives a predicate representing the “where” clause. The following code represents the final implementation of this repository.public class DataServiceRepository: IRepository { ResourceRepositoryContext context; public DataServiceRepository() : this (new DataServiceContext()) { } public DataServiceRepository(DataServiceContext context) { this.context = context; } private static string ResolveEntitySet(Type type) { var entitySetAttribute = (EntitySetAttribute)type.GetCustomAttributes(typeof(EntitySetAttribute), true).FirstOrDefault(); if (entitySetAttribute != null) return entitySetAttribute.EntitySet; return null; } public T Create<T>() where T : new() { var collection = new DataServiceCollection<T>(this.context); var entity = new T(); collection.Add(entity); return entity; } public void Update<T>(T entity) { this.context.UpdateObject(entity); } public void Delete<T>(T entity) { this.context.DeleteObject(entity); } public void Attach<T>(T entity) { var collection = new DataServiceCollection<T>(this.context); collection.Load(entity); } public IQueryable<T> Retrieve<T>(Expression<Func<T, bool>> predicate, params Expression<Func<T, object>>[] eagerProperties) { var entitySet = ResolveEntitySet(typeof(T)); var query = context.CreateQuery<T>(entitySet); foreach (var e in eagerProperties) { query = query.Expand(e); } return query.Where(predicate); } public IQueryable<T> RetrieveAll<T>(params Expression<Func<T, object>>[] eagerProperties) { var entitySet = ResolveEntitySet(typeof(T)); var query = context.CreateQuery<T>(entitySet); foreach (var e in eagerProperties) { query = query.Expand(e); } return query; } public void SaveChanges() { this.context.SaveChanges(SaveChangesOptions.Batch); } } For instance, you can use the following code to retrieve customers with First name equal to “John”, and all their orders in a single call. repository.Retrieve<Customer>(    c => c.FirstName == “John”, //Where    c => c.Orders.SubExpand(o => o.Items)); In case, you want to have some pre-defined queries that you are going to use across several places, you can put them in an specific class. public static class CustomerQueries {   public static Expression<Func<Customer, bool>> LastNameEqualsTo(string lastName)   {     return c => c.LastName == lastName;   } } And then, use it with the repository. repository.Retrieve<Customer>(    CustomerQueries.LastNameEqualsTo("foo"),    c => c.Orders.SubExpand(o => o.Items));

  Read the article

• datagrid binding

  - by abcdd007

  using System; using System.Data; using System.Configuration; using System.Collections; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; using System.Data.SqlClient; public partial class OrderMaster : System.Web.UI.Page { BLLOrderMaster objMaster = new BLLOrderMaster(); protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { SetInitialRow(); string OrderNumber = objMaster.SelectDetails().ToString(); if (OrderNumber != "") { txtOrderNo.Text = OrderNumber.ToString(); txtOrderDate.Focus(); } } } private void InsertEmptyRow() { DataTable dt = new DataTable(); DataRow dr = null; dt.Columns.Add(new DataColumn("ItemCode", typeof(string))); dt.Columns.Add(new DataColumn("Description", typeof(string))); dt.Columns.Add(new DataColumn("Unit", typeof(string))); dt.Columns.Add(new DataColumn("Qty", typeof(string))); dt.Columns.Add(new DataColumn("Rate", typeof(string))); dt.Columns.Add(new DataColumn("Disc", typeof(string))); dt.Columns.Add(new DataColumn("Amount", typeof(string))); for (int i = 0; i < 5; i++) { dr = dt.NewRow(); dr["ItemCode"] = string.Empty; dr["Description"] = string.Empty; dr["Unit"] = string.Empty; dr["Qty"] = string.Empty; dr["Rate"] = string.Empty; dr["Disc"] = string.Empty; dr["Amount"] = string.Empty; dt.Rows.Add(dr); } //GridView1.DataSource = dt; //GridView1.DataBind(); } private void SetInitialRow() { DataTable dt = new DataTable(); DataRow dr = null; dt.Columns.Add(new DataColumn("RowNumber", typeof(string))); dt.Columns.Add(new DataColumn("ItemCode", typeof(string))); dt.Columns.Add(new DataColumn("Description", typeof(string))); dt.Columns.Add(new DataColumn("Unit", typeof(string))); dt.Columns.Add(new DataColumn("Qty", typeof(string))); dt.Columns.Add(new DataColumn("Rate", typeof(string))); dt.Columns.Add(new DataColumn("Disc", typeof(string))); dt.Columns.Add(new DataColumn("Amount", typeof(string))); dr = dt.NewRow(); dr["RowNumber"] = 1; dr["ItemCode"] = string.Empty; dr["Description"] = string.Empty; dr["Unit"] = string.Empty; dr["Qty"] = string.Empty; dr["Rate"] = string.Empty; dr["Disc"] = string.Empty; dr["Amount"] = string.Empty; dt.Rows.Add(dr); //Store DataTable ViewState["OrderDetails"] = dt; Gridview1.DataSource = dt; Gridview1.DataBind(); } protected void AddNewRowToGrid() { int rowIndex = 0; if (ViewState["OrderDetails"] != null) { DataTable dtCurrentTable = (DataTable)ViewState["OrderDetails"]; DataRow drCurrentRow = null; if (dtCurrentTable.Rows.Count > 0) { for (int i = 1; i <= dtCurrentTable.Rows.Count; i++) { //extract the TextBox values TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("txtItemCode"); TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("txtdescription"); TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("txtunit"); TextBox box4 = (TextBox)Gridview1.Rows[rowIndex].Cells[4].FindControl("txtqty"); TextBox box5 = (TextBox)Gridview1.Rows[rowIndex].Cells[5].FindControl("txtRate"); TextBox box6 = (TextBox)Gridview1.Rows[rowIndex].Cells[6].FindControl("txtdisc"); TextBox box7 = (TextBox)Gridview1.Rows[rowIndex].Cells[7].FindControl("txtamount"); drCurrentRow = dtCurrentTable.NewRow(); drCurrentRow["RowNumber"] = i + 1; drCurrentRow["ItemCode"] = box1.Text; drCurrentRow["Description"] = box2.Text; drCurrentRow["Unit"] = box3.Text; drCurrentRow["Qty"] = box4.Text; drCurrentRow["Rate"] = box5.Text; drCurrentRow["Disc"] = box6.Text; drCurrentRow["Amount"] = box7.Text; rowIndex++; } //add new row to DataTable dtCurrentTable.Rows.Add(drCurrentRow); //Store the current data to ViewState ViewState["OrderDetails"] = dtCurrentTable; //Rebind the Grid with the current data Gridview1.DataSource = dtCurrentTable; Gridview1.DataBind(); } } else { // } //Set Previous Data on Postbacks SetPreviousData(); } private void SetPreviousData() { int rowIndex = 0; if (ViewState["OrderDetails"] != null) { DataTable dt = (DataTable)ViewState["OrderDetails"]; if (dt.Rows.Count > 0) { for (int i = 1; i < dt.Rows.Count; i++) { TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("txtItemCode"); TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("txtdescription"); TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("txtunit"); TextBox box4 = (TextBox)Gridview1.Rows[rowIndex].Cells[4].FindControl("txtqty"); TextBox box5 = (TextBox)Gridview1.Rows[rowIndex].Cells[5].FindControl("txtRate"); TextBox box6 = (TextBox)Gridview1.Rows[rowIndex].Cells[6].FindControl("txtdisc"); TextBox box7 = (TextBox)Gridview1.Rows[rowIndex].Cells[7].FindControl("txtamount"); box1.Text = dt.Rows[i]["ItemCode"].ToString(); box2.Text = dt.Rows[i]["Description"].ToString(); box3.Text = dt.Rows[i]["Unit"].ToString(); box4.Text = dt.Rows[i]["Qty"].ToString(); box5.Text = dt.Rows[i]["Rate"].ToString(); box6.Text = dt.Rows[i]["Disc"].ToString(); box7.Text = dt.Rows[i]["Amount"].ToString(); rowIndex++; } dt.AcceptChanges(); } ViewState["OrderDetails"] = dt; } } protected void BindOrderDetails() { DataTable dtOrderDetails = new DataTable(); if (ViewState["OrderDetails"] != null) { dtOrderDetails = (DataTable)ViewState["OrderDetails"]; } else { dtOrderDetails.Columns.Add(""); dtOrderDetails.Columns.Add(""); dtOrderDetails.Columns.Add(""); dtOrderDetails.Columns.Add(""); dtOrderDetails.Columns.Add(""); dtOrderDetails.Columns.Add(""); dtOrderDetails.AcceptChanges(); DataRow dr = dtOrderDetails.NewRow(); dtOrderDetails.Rows.Add(dr); ViewState["OrderDetails"] = dtOrderDetails; } if (dtOrderDetails != null) { Gridview1.DataSource = dtOrderDetails; Gridview1.DataBind(); if (Gridview1.Rows.Count > 0) { ((LinkButton)Gridview1.Rows[Gridview1.Rows.Count - 1].FindControl("btnDelete")).Visible = false; } } } protected void btnSave_Click(object sender, EventArgs e) { if (txtOrderDate.Text != "" && txtOrderNo.Text != "" && txtPartyName.Text != "" && txttotalAmount.Text !="") { BLLOrderMaster bllobj = new BLLOrderMaster(); DataTable dtdetails = new DataTable(); UpdateItemDetailRow(); dtdetails = (DataTable)ViewState["OrderDetails"]; SetValues(bllobj); int k = 0; k = bllobj.Insert_Update_Delete(1, bllobj, dtdetails); if (k > 0) { ScriptManager.RegisterStartupScript(this, this.GetType(), "Login Denied", "<Script>alert('Order Code Alraddy Exist');</Script>", false); } else { ScriptManager.RegisterStartupScript(this, this.GetType(), "Login Denied", "<Script>alert('Record Saved Successfully');</Script>", false); } dtdetails.Clear(); SetInitialRow(); txttotalAmount.Text = ""; txtOrderNo.Text = ""; txtPartyName.Text = ""; txtOrderDate.Text = ""; txttotalQty.Text = ""; string OrderNumber = objMaster.SelectDetails().ToString(); if (OrderNumber != "") { txtOrderNo.Text = OrderNumber.ToString(); txtOrderDate.Focus(); } } else { txtOrderNo.Text = ""; } } public void SetValues(BLLOrderMaster bllobj) { if (txtOrderNo.Text != null && txtOrderNo.Text.ToString() != "") { bllobj.OrNumber = Convert.ToInt16(txtOrderNo.Text); } if (txtOrderDate.Text != null && txtOrderDate.Text.ToString() != "") { bllobj.Date = DateTime.Parse(txtOrderDate.Text.ToString()).ToString("dd/MM/yyyy"); } if (txtPartyName.Text != null && txtPartyName.Text.ToString() != "") { bllobj.PartyName = txtPartyName.Text; } bllobj.TotalBillAmount = txttotalAmount.Text == "" ? 0 : int.Parse(txttotalAmount.Text); bllobj.TotalQty = txttotalQty.Text == "" ? 0 : int.Parse(txttotalQty.Text); } protected void txtdisc_TextChanged(object sender, EventArgs e) { double total = 0; double totalqty = 0; foreach (GridViewRow dgvr in Gridview1.Rows) { TextBox tb = (TextBox)dgvr.Cells[7].FindControl("txtamount"); double sum; if (double.TryParse(tb.Text.Trim(), out sum)) { total += sum; } TextBox tb1 = (TextBox)dgvr.Cells[4].FindControl("txtqty"); double qtysum; if (double.TryParse(tb1.Text.Trim(), out qtysum)) { totalqty += qtysum; } } txttotalAmount.Text = total.ToString(); txttotalQty.Text = totalqty.ToString(); AddNewRowToGrid(); Gridview1.TabIndex = 1; } public void UpdateItemDetailRow() { DataTable dt = new DataTable(); if (ViewState["OrderDetails"] != null) { dt = (DataTable)ViewState["OrderDetails"]; } if (dt.Rows.Count > 0) { for (int i = 0; i < Gridview1.Rows.Count; i++) { dt.Rows[i]["ItemCode"] = (Gridview1.Rows[i].FindControl("txtItemCode") as TextBox).Text.ToString(); if (dt.Rows[i]["ItemCode"].ToString() == "") { dt.Rows[i].Delete(); break; } else { dt.Rows[i]["Description"] = (Gridview1.Rows[i].FindControl("txtdescription") as TextBox).Text.ToString(); dt.Rows[i]["Unit"] = (Gridview1.Rows[i].FindControl("txtunit") as TextBox).Text.ToString(); dt.Rows[i]["Qty"] = (Gridview1.Rows[i].FindControl("txtqty") as TextBox).Text.ToString(); dt.Rows[i]["Rate"] = (Gridview1.Rows[i].FindControl("txtRate") as TextBox).Text.ToString(); dt.Rows[i]["Disc"] = (Gridview1.Rows[i].FindControl("txtdisc") as TextBox).Text.ToString(); dt.Rows[i]["Amount"] = (Gridview1.Rows[i].FindControl("txtamount") as TextBox).Text.ToString(); } } dt.AcceptChanges(); } ViewState["OrderDetails"] = dt; } }

  Read the article

• Unity - Mecanim & Rigidbody on Third Person Controller - Gravity bug?

  - by Celtc

  I'm working on a third person controller which uses physX to interact with the other objects (using the Rigidbody component) and Mecanim to animate the character. All the animations used are baked to Y, and the movement on this axis is controlled by the gravity applied by the rigidbody component. The configuration of the falling animation: And the character components configuration: Since the falling animation doesn't have root motion on XZ, I move the character on XZ by code. Like this: // On the Ground if (IsGrounded()) { GroundedMovementMgm(); // Stores the velocity velocityPreFalling = rigidbody.velocity; } // Mid-Air else { // Continue the pre falling velocity rigidbody.velocity = new Vector3(velocityPreFalling.x, rigidbody.velocity.y, velocityPreFalling.z); } The problem is that when the chracter starts falling and hit against a wall in mid air, it gets stuck to the wall. Here are some pics which explains the problems: Hope someone can help me. Thanks and sory for my bad english! PD.: I was asked for the IsGrounded() function, so I'm adding it: void OnCollisionEnter(Collision collision) { if (!grounded) TrackGrounded(collision); } void OnCollisionStay(Collision collision) { TrackGrounded(collision); } void OnCollisionExit() { grounded = false; } public bool IsGrounded() { return grounded; } private void TrackGrounded(Collision collision) { var maxHeight = capCollider.bounds.min.y + capCollider.radius * .9f; foreach (var contact in collision.contacts) { if (contact.point.y < maxHeight && Vector3.Angle(contact.normal, Vector3.up) < maxSlopeAngle) { grounded = true; break; } } } I'll also add a LINK to download the project if someone wants it.

  Read the article

• Testing Routes in ASP.NET MVC with MvcContrib

  - by Guilherme Cardoso

  I've decide to write about unit testing in the next weeks. If we decide to develop with Test-Driven Developement pattern, it's important to not forget the routes. This article shows how to test routes. I'm importing my routes from my RegisterRoutes method from the Global.asax of Project.Web created by default (in SetUp). I'm using ShouldMapTp() from MvcContrib: http://mvccontrib.codeplex.com/ The controller is specified in the ShouldMapTo() signature, and we use lambda expressions for the action and parameters that are passed to that controller. [SetUp] public void Setup() { Project.Web.MvcApplication.RegisterRoutes(RouteTable.Routes); } [Test] public void Should_Route_HomeController() { "~/Home" .ShouldMapTo<HomeController>(action => action.Index()); } [Test] public void Should_Route_EventsController() { "~/Events" .ShouldMapTo<EventsController>(action => action.Index()); "~/Events/View/44/Concert-DevaMatri-22-January-" .ShouldMapTo<EventosController>(action => action.Read(1, "Title")); // In this example,44 is the Id for my Event and "Concert-DevaMatri-22-January" is the title for that Event } [TearDown] public void teardown() { RouteTable.Routes.Clear(); }

  Read the article

< Previous Page | 54 55 56 57 58 59 60 61 62 63 64 65  | Next Page >