我有一个 surfaceview 和一个 gameThread 类。 gameThread 在 SurfaceView 类上不断更新和绘制。

现在，当我退出应用程序时(通过按主页或后退按钮)，我收到一条消息，提示应用程序强制关闭。那是因为 GameThread 仍然试图在删除的表面 View 上绘制...

那么如何在没有收到强制关闭通知的情况下正确结束应用程序呢？我希望 GameThread 类在按下后退按钮时停止。当按下主页并在后台运行时，它应该会暂停。当重新进入仍在运行的游戏时，它应该恢复....

有什么想法吗？

这是我的 GameThread 类:

public class GameThread extends Thread{

private GameView view;
public boolean isRunning = false;

public GameThread(GameView view) {
    this.view = view;
}

public void setRunning(boolean setRunning) {
    isRunning = setRunning;
}

public void run() {
    while(isRunning) {
        Canvas c = null;
        view.update();
        try {
            c = view.getHolder().lockCanvas();
            synchronized (view.getHolder()) {
                view.draw(c);
            }
        }finally {
            if(c != null) {
                view.getHolder().unlockCanvasAndPost(c);
            }
        }
    }
}

它不断更新我的 GameView 类:

公共(public)类 GameView 扩展了 SurfaceView{

private GameThread gameThread;

public GameView(Context context, Activity activity) {
    super(context);
    gameThread = new GameThread(this);
    init();
    holder = getHolder();
    holder.addCallback(new SurfaceHolder.Callback() {

        @Override
        public void surfaceDestroyed(SurfaceHolder holder) {

        }
        @Override
        public void surfaceCreated(SurfaceHolder holder) {
            gameThread.setRunning(true);
            gameThread.start();

        }
        @Override
        public void surfaceChanged(SurfaceHolder holder, int format, int width,
                int height) {
        }
    });
}


public void init() {

}

public void update() {

}

public void draw(Canvas canvas) {
    super.draw(canvas);

}
}

当按下主页时，我的 logcat 会显示:

02-24 18:24:59.336: E/SurfaceHolder(839): Exception locking surface
02-24 18:24:59.336: E/SurfaceHolder(839): java.lang.IllegalStateException: Surface has already been released.
02-24 18:24:59.336: E/SurfaceHolder(839):   at android.view.Surface.checkNotReleasedLocked(Surface.java:437)
02-24 18:24:59.336: E/SurfaceHolder(839):   at android.view.Surface.lockCanvas(Surface.java:245)
02-24 18:24:59.336: E/SurfaceHolder(839):   at android.view.SurfaceView$4.internalLockCanvas(SurfaceView.java:872)

主要 Activity :

public class MainActivity extends Activity {

private RelativeLayout relativeLayout;
private GameView gameView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    gameView = new GameView(this, this);
    setContentView(R.layout.activity_main);
    relativeLayout = (RelativeLayout)findViewById(R.id.mainView);
    relativeLayout.addView(gameView);
}

@Override
public void onBackPressed() {
    // TODO Auto-generated method stub
    super.onBackPressed();
    gameView.onBackPressed();
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

}

最佳答案

您可以像这样更改您的代码。

在 GameView

@Override
    public void surfaceCreated(SurfaceHolder holder) {
        MainActivity obj=new MainActivity();
        stop=obj.getBoolean(); //receive status of boolean from main activity

        //stop is boolean set if backPressed in main activity
        if(!stop){ 
        gameThread.setRunning(true);
        gameThread.start();
        }
        else
            gameThread.setRunning(false);
    }

在 MainActivity 中

public Boolean getBoolean(){
return stop;    
} 

public void setBoolean(Boolean bools){
stop=bools;
}

@Override
public void onBackPressed() {
// TODO Auto-generated method stub
super.onBackPressed();

stop=true;
setBoolean(stop);

try{
Thread.sleep(200); // Be safeside and wait for Game thread to finish
}
catch(Exception e){
e.printStackTrace();
}

MainActivity.finish();
}

在 backPress 之前调用 setBoolean 一次，否则会报错。根据您的需要修改代码。

希望对您有所帮助。干杯。 :)

关于android - 在退出应用程序时结束 SurfaceView 和 GameThread，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21994404/