通过拖动到角落或按钮来删除ImageView

Question

我有一个主要的大ImageView和4-5小ImageView。小ImageView可以使用zoom-in-out，drag to change place和rotate，全部来自我在自定义onTouchEvent中构建的ImageView。

自从使用onTouch事件进行拖动（移动）ImageView后，我无法使用OnDragListener删除小ImageView。我想通过移动到屏幕的一角或特定按钮来删除。

请帮我找一个解决方案。

public boolean onTouchEvent(MotionEvent event) {
    this.setScaleType(ImageView.ScaleType.MATRIX);
    float scale;

    switch (event.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN: //first finger down only
            savedMatrix.set(matrix);
            start.set(event.getX(), event.getY());

            Log.d("amin", "mode=DRAG");
            break;

        case MotionEvent.ACTION_POINTER_DOWN:
            oldDist = spacing(event);
            if (oldDist > 10f) {
                savedMatrix.set(matrix);
                midPoint(mid, event);
                mode = ZOOM;
            }
            lastEvent = new float[4];
            lastEvent[0] = event.getX(0);
            lastEvent[1] = event.getX(1);
            lastEvent[2] = event.getY(0);
            lastEvent[3] = event.getY(1);
             d = rotation(event);
            break;

        case MotionEvent.ACTION_UP: //first finger lifted

        case MotionEvent.ACTION_POINTER_UP: //second finger lifted
            mode = NONE;
            Log.d("amin", "mode=NONE" );
            break;


        case MotionEvent.ACTION_MOVE:
                if (mode == ZOOM && event.getPointerCount() == 2) {
                float newDist = spacing(event);
                matrix.set(savedMatrix);
                if (newDist > 10f) {
                    scale = newDist / oldDist;
                    matrix.postScale(scale, scale, mid.x, mid.y);
                }
                if (lastEvent != null) {
                     newRot = rotation(event);
                    float r = newRot - d;
                    matrix.postRotate(r, this.getMeasuredWidth() / 2,
                            this.getMeasuredHeight() / 2);
                }
            }else{
                 mode = DRAG;
                 // matrix.set(savedMatrix);
                  //matrix.postTranslate(event.getX() - start.x, event.getY()-start.y);
                 //this.layout((int)(start.x- (this.getWidth())),(int)(start.y- (this.getHeight())),(int) start.x, (int) start.y);
                 RelativeLayout.LayoutParams layoutPrarms = (RelativeLayout.LayoutParams)this.getLayoutParams();
                 int left = layoutPrarms.leftMargin + (int)(event.getX() - start.x);
                 int top = layoutPrarms.topMargin + (int)(event.getY() - start.y);
                 layoutPrarms.leftMargin = left;
                 layoutPrarms.topMargin = top;
                 this.setLayoutParams(layoutPrarms);
                 Log.d("amin", "mode=Drag" );


             }

            break;

    }
    // Perform the transformation
    this.setImageMatrix(matrix);

    return true;
 }