Question

我正在创建一个应用程序，其中在运行时给出的两个点之间生成一条线我看到的问题是，在我的模拟器上每次点击都会调用onTouch()两次。我知道检查了两个操作（ACTION_DOWN＆amp; ACTION_UP）。但我希望我的应用只需拨打onTouch()一次。请给我一些想法。这是我使用的代码：

SurfaceView surfaceview = new SurfaceView(getContext());
SurfaceHolder h = surfaceview.getHolder();
int action = event.getActionMasked();
synchronized(h) {
    if (action == MotionEvent.ACTION_DOWN && action!=MotionEvent.ACTION_CANCEL)// && flag==true)
    {
        Log.d("TouchView","ACTION_DOWN ");
        Point pointer = new Point();
        pointer.x = (int) event.getX();
        pointer.y = (int) event.getY();
        touchPoint.add(pointer);
        view.invalidate();
        Log.d("MotionEvent.ACTION_DOWN", "point: " + pointer);
        action = MotionEvent.ACTION_CANCEL;
        flag = false;
    }
    else if(action == MotionEvent.ACTION_UP && action!=MotionEvent.ACTION_CANCEL)// && flag==true)
    {
        Log.d("TouchView","ACTION_UP");
        Point pointer = new Point();
        pointer.x = (int) event.getX();
        pointer.y = (int) event.getY();
        touchPoint.add(pointer);
        view.invalidate();
        Log.d("MotionEvent.ACTION_UP", "point: " + pointer);
        action = MotionEvent.ACTION_CANCEL;
        flag = false;
    }
    else return false;
}

Answer 1

将为每个MotionEvent.ACTION_DOWN，MotionEvent.ACTION_UP和MotionEvent.ACTION_MOVE调用touchListener。所以如果你只想执行一次代码，即MotionEvent.ACTION_DOWN

onTouch()
 if (event.getAction() == MotionEvent.ACTION_DOWN) {
//your code 
}

Answer 2

或者只使用onClickListener：

        myButton.setOnClickListener(new Button.OnClickListener() {
            @Override
            public void onClick(View v) {
                //do what you gotta do
            }
        });

Answer 3

有时候在同一个父对象下处理多个视图会导致onTouch被调用很多次（如果它们位于彼此之上），对我而言，解决方案是

onTouch{ ...
        if(event.getAction() == MotionEvent.ACTION_DOWN && isTouchEnabled()){
            enableTouch(false);
            //add your code here 
            
            //then enableTouch at the end 
            this.postDelayed(new Runnable() {
                @Override
                public void run() {
                    enableTouch(true);

                }
            }, 500);
      }
      add static variable touch
    private static boolean enabled = true;
      
    private void enableTouch(boolean enabled){
        this.enabled = enabled;
    }

    private boolean isTouchEnabled(){
        return enabled;
    }

OnTouchListener的Ontouch事件在android中被调用两次

3 个答案: