Java Android中的游戏线程执行未正确恢复

我正在开发一个简单的游戏，它运行在自己的线程中。当我启动应用程序时，一切都很好。线程被初始化，更新和渲染函数从线程执行，这很好

如果退出应用程序，线程将暂停。当我再次启动应用程序时，线程恢复正常。执行更新和渲染功能。再说一次，这太棒了

问题是，我按下电源按钮使设备休眠。当我从该状态恢复应用程序时，渲染功能似乎工作正常；它将所有元素背景、精灵等精确地绘制在我按下按钮之前的位置。但是：精灵不再是动画！经过一点跟踪和故障排除，我发现尽管running标志设置为TRUE，但RUN函数似乎不再运行了！另一方面，我不明白为什么渲染函数可以工作，但更新函数不能，除非应用程序从其他方法渲染对象？不顾一切的

我从两个可能的角度研究这个问题；我要么在Android操作线程的方式上遗漏了什么，要么这与对象中的成员变量被重置的事实有关

有人能回顾一下我在下面发布的基本代码，并就如何改进线程操作提出建议吗？我是一个聪明的人，我读过很多关于这个问题的不同来源的文章，现在比以往任何时候都更加困惑！我在这条路上走对了吗，还是有更聪明的方法？我真的需要一个单独的游戏线程，还是可以用设备的主线程来运行它

谢谢你的反馈

public class GameThread extends Thread {
    private boolean running=false;
    private SurfaceHolder surfaceHolder;
    private GameView gameView;

    public GameThread(SurfaceHolder surfaceHolder, GameView gameView){
        super();
        this.surfaceHolder = surfaceHolder;
        this.gameView = gameView;
    }

    @Override
    public void run(){
        Canvas canvas;

        //  THIS ONLY RUNS ONCE!
        //  WHEN I TURN THE POWER OFF AND BACK ON, THE RUN() METHOD DOES NOT RUN!
        //  ODDLY ENOUGH, IF I WERE TO EXIT THE APP, AND GO BACK IN, IT WORKS FINE!
        //  THE running FLAG SEEMS TO CHANGE PROPERLY WHEN PAUSING OR RESUMING (SEE gameView, BELOW).
        while (running){
            canvas = null;
            try {
                canvas = this.surfaceHolder.lockCanvas();
                synchronized (surfaceHolder){
                    gameView.update();
                    gameView.render(canvas);
                }
            } finally {
                if (canvas!=null)
                    surfaceHolder.unlockCanvasAndPost(canvas);
            }
        }
    }
    public void setRunning(boolean running){
        this.running = running;
    }
}

public class GameView extends SurfaceView implements SurfaceHolder.Callback {
    private GameThread thread;
    private GameScreen gameScreen;

    public GameView(Context context) {
        super(context);
        gameScreen = new GameScreen(context);
        setFocusable(true);
        thread = new GameThread(getHolder(), this);
        getHolder().addCallback(this);
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        thread = new GameThread(getHolder(), this);
        thread.setRunning(true);
        thread.start();
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        boolean retry = true;
        while (retry){
            try {
                thread.join();
                retry = false;
            } catch (InterruptedException e){
                // Do nothing; continue trying
            }
        }
    }

    public void render(Canvas canvas){
        gameScreen.draw(canvas);
    }   

    public void update(){   
        gameScreen.update();
    }

    @Override
    public boolean onTouchEvent(MotionEvent event){
        gameScreen.touch(event);
    }

    public void resume(){
        // TODO: Resume events go here
        thread.setRunning(true);
    }

    public void pause(){
        // TODO: Pause events go here
        thread.setRunning(false);
    }
}

public class GameScreen {
    public GameScreen(Context context){
        // Initialize private variables here
    }

    public void draw(Canvas canvas){
        // Draw events go here
    }

    public void update(){
        // Update events go here
    }

    public void touch(MotionEvent event){
        // Touch events go here
    }
}

---

在尝试发布画布之前，需要执行update方法。仍然不确定这是为什么，但它现在按预期工作

    Canvas canvas = null;
    while (running){
        gameView.update();

        try {
            canvas = this.surfaceHolder.lockCanvas();
            synchronized (surfaceHolder){

                gameView.render(canvas);
            }
        } finally {
            if (canvas!=null)
                surfaceHolder.unlockCanvasAndPost(canvas);
        }
    }
}