Android View onTouchEvent

重写onTouchEvent方法，将返回写成true消费掉触摸事件，
然后根据当前触摸的坐标点位移View

@Override
    public boolean onTouchEvent(MotionEvent event) {
        int rawX = (int)event.getRawX();
        int rawY = (int)event.getRawY();
        switch (event.getAction()){
            case MotionEvent.ACTION_DOWN:
                lastX = rawX;
                lastY = rawY;
                break;
            case MotionEvent.ACTION_MOVE:
                int offsetX = rawX - lastX;
                int offsetY = rawY - lastY;
                offsetLeftAndRight(offsetX);
                offsetTopAndBottom(offsetY);
                lastX = rawX;
                lastY = rawY;
                break;
            case MotionEvent.ACTION_UP:

                break;
        }
        return true;
    }

效果

TIM图片20190306171533.gif