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public class MyGameView extends View implements OnTouchListener{

    static int x, y;
    final static int radius = 25;
    private int androidX;
    private int androidY;
    Paint paint;
    Bitmap android;
    boolean touch = false;
    Handler handler = new Handler();

    private Runnable r = new Runnable() {

        @Override
        public void run() {
            invalidate();

        }


    };

    private Runnable r2 = new Runnable() {

        @Override
        public void run() {
            androidX = (int) Math.ceil(Math.random() * (MyGameView.this.getWidth()-android.getWidth()));
            androidY = (int) Math.ceil(Math.random() * (MyGameView.this.getHeight()-android.getHeight()));
        }
    };

    public MyGameView(Context context) {
        super(context);
        paint = new Paint();
        paint.setAntiAlias(true); // smooth rendering
        android = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
        setFocusable(true);
        setOnTouchListener(this);

    }


    @Override
    protected void onDraw(Canvas canvas) {
        if(touch == true){
            paint.setARGB(255, 222, 78, 112);
            canvas.drawBitmap(android, androidX, androidY, null);
            canvas.drawCircle(x,y,radius,paint);
        }
        handler.postDelayed(r, 1000);
        handler.postDelayed(r2, 3000);
        super.onDraw(canvas);
    }


    @Override
    public boolean onTouch(View view, MotionEvent event) {
        x=(int)event.getX()-(radius/2);      
        y=(int)event.getY()-(radius/2);
        switch(event.getAction()){
        case MotionEvent.ACTION_DOWN:
                touch = true;
                break;

        case MotionEvent.ACTION_UP:
                touch = false;
                break;
        }
        invalidate();  
        return true;
    }

}

这是我的代码我想要的是当我握住手指时，位图开始在随机位置 x y 处每 3 秒绘制一次。一切正常，但问题图像疯狂地绘制到每个位置，我不知道该怎么做，我尝试在 ACTION_DOWN 上调用 invalidate() 但现在我的圆圈每 3 秒绘制一次到我触摸的位置。任何帮助表示赞赏。

4

1 回答 1

3

我不相信我完全理解你想要什么，但你的代码的问题如下：onDraw经常被调用。在每个调用中，您都会r2延迟 3 秒运行。如此有效，r2只是经常运行onDraw，但第一次延迟了 3 秒。

我认为你想要做的是r2在一个单独的线程中运行，并每 3 秒不断更新位置，如：

public class MyGameView extends View implements OnTouchListener{

    static int x, y;
    final static int radius = 25;
    private int androidX;
    private int androidY;
    Paint paint;
    Bitmap android;
    boolean touch = false;

    private Runnable r2 = new Runnable() {

        @Override
        public void run() {
            androidX = (int) Math.ceil(Math.random() * (MyGameView.this.getWidth()-android.getWidth()));
            androidY = (int) Math.ceil(Math.random() * (MyGameView.this.getHeight()-android.getHeight()));
        }
    };

    public MyGameView(Context context) {
        super(context);
        paint = new Paint();
        paint.setAntiAlias(true); // smooth rendering
        android = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
        setFocusable(true);
        setOnTouchListener(this);

        new Thread(r2).start(); // run r2 in a separate thread
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if(touch == true){
            paint.setARGB(255, 222, 78, 112);
            canvas.drawBitmap(android, androidX, androidY, null);
            canvas.drawCircle(x,y,radius,paint);
        }        
    }

    @Override
    public boolean onTouch(View view, MotionEvent event) {
        x=(int)event.getX()-(radius/2);      
        y=(int)event.getY()-(radius/2);
        switch(event.getAction()){
        case MotionEvent.ACTION_DOWN:
                touch = true;
                break;
        case MotionEvent.ACTION_UP:
                touch = false;
                break;
        }
        return true;
    }
}
于 2013-06-08T22:37:44.447 回答