android - 多次更新 SurfaceView 的更好方法？

Question

我正在使用 a SurfaceView，我必须尽快更新它。由于不会自动调用 onDraw 方法，因此我必须显式调用。所以我的第一次尝试是在线程上，但我有一些滞后。有更好的方法来做到这一点吗？如果有更好的解决方案，请您解释一下吗？我是 Android 世界的新手！

---

到目前为止我所拥有的

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

Answer 1

这是我用作渲染线程的代码。fps 取决于更新帧。我通常以 30 fps 运行我的游戏。（有些代码你不需要，但我很高兴你能找到你正在寻找的部分。）

public class RenderView extends SurfaceView implements Runnable {


    Game game;
    Bitmap gameScreen;
    Thread gameloop;
    SurfaceHolder holder;
    boolean running;

    int sleepTime;
    int numberOfFramesSkipped;
    int maxFrameSkips;
    long beginTime;
    long endTime;
    long lastTime;
    int differenceTime;
    int framePeriod;
    Canvas frameBuffer;
    int frameCount;

    public RenderView(int fps, int maxFrameSkips) {
        super(game);
        this.gameScreen = gameScreen;
        this.holder = getHolder();
        this.framePeriod = 1000/fps;
        this.maxFrameSkips = maxFrameSkips;
        lastTime = System.currentTimeMillis();
        beginTime = System.currentTimeMillis();
    }

    @Override
    public void run() {

        while(running == true) {
            if(holder.getSurface().isValid()) {

                beginTime = System.currentTimeMillis();

                    // call your update method here
                // render here
                    frameBuffer = holder.lockCanvas();
                    this.onDraw();
                    holder.unlockCanvasAndPost(frameBuffer);

                // Frame Per Second Count
                frameCount++;

                if(lastTime + 1000 < System.currentTimeMillis()) {
                    lastTime = System.currentTimeMillis();
                    frameCount = 0;
                }

                endTime = System.currentTimeMillis();;
                differenceTime = (int) (endTime - beginTime);
                sleepTime = (int) (framePeriod - differenceTime);

                if(sleepTime > 0) {
                    try {
                        Thread.sleep(sleepTime);
                    } catch (InterruptedException exception) {
                        exception.printStackTrace();
                    }
                }
                else {
                    while(sleepTime < 0 && numberOfFramesSkipped < this.maxFrameSkips) {
                        // Call your update method here
                        sleepTime += framePeriod;
                        numberOfFramesSkipped++;
                    }
                }


            }


        }

    }

    private void renderFrameBuffer() {
        // Update the current virtual screen image
        game.getCurrentScreen().render();
        // Render the current virtual screen to the real phone screen
        frameBuffer = holder.lockCanvas();
        if(frameBuffer != null) { // Fix for mysterious bug ( FATAL EXCEPTION: Thread)
            // The viewing area of our virtual screen on our real screen
            // Composition
            // First layer (bottom)
                frameBuffer.drawBitmap(this.gameScreen, null, game.getWSScreen().getGameScreendst(), null);
            // Second layer (top)
                frameBuffer.drawBitmap(this.gameScreenExtended, null, game.getWSScreen().getGameScreenextendeddst(), null);

            holder.unlockCanvasAndPost(frameBuffer);
        }
        else {
            gameEngineLog.e(classTAG, "Surface has not been created or otherwise cannot be edited");
        }
    }

    public void resume() { 
        this.running = true;
        gameloop = new Thread(this);
        gameloop.start();         
    }   

    public void pause() { 
        this.running = false;
        running = false;                        
        while(true) {
            try {
                gameloop.join();
                break;
            } catch (InterruptedException e) {
                // retry
            }
        }
    }

}

public void onDraw() {

}

我建议你看看这个链接或看看 http://code.google.com/p/beginning-android-games/ 或http://www.edu4java.com/en/androidgame/androidgame3.html