Android firing onTouch event for multiple ImageVie

问题:

I have several ImageViews, and I want the onTouch event to fire for each of them when I drag my finger across multiple images. At present the onTouch event is only firing on the first ImageView (or actually on multiple ImageViews but only when multitouching the screen). Pseudo code:

            for(int i=0;i<5;i++){
              ImageView img=new ImageView(this);
              LinearLayout.LayoutParams layoutParams=new LinearLayout.LayoutParams(width,height);
              img.setImageResource(R.drawable.cell);
              img.setOnTouchListener(this);
              mainLayout.addView(img,layoutParams);
            }
            ...

            public boolean onTouch (View v, MotionEvent event){
              Log.d("MY_APP","View: " + v.getId());
              return false;
            }

Am I barking up completely the wrong tree?

Thanks for any help.

回答1:

I think you need to use move event rather than touch event and compare getX and getY with the location of your views.

     @Override
    public boolean onTouchEvent(MotionEvent ev) {

        final int action = ev.getAction();

        switch (action) {

            // MotionEvent class constant signifying a finger-down event

            case MotionEvent.ACTION_DOWN: {
                break;
            }

            // MotionEvent class constant signifying a finger-drag event  

            case MotionEvent.ACTION_MOVE: {

                    X = ev.getX();
                    Y = ev.getY();
                    //compare here using a loop of your views
                    break;

            }

            // MotionEvent class constant signifying a finger-up event

            case MotionEvent.ACTION_UP:

                break;

        }
        return true;
    }

回答2:

Yes, I had the same problem. The answer was to create a touch listener for the layout I embed my ImageViews in and then to calculate the X, Y position to know above which of my View am I. OnTouchListener is called only for the view it is connected to. I mean if it is called for an ImageView it won't fire until you start your motion onto that ImageView, as far as I know.