Question

我正在尝试在recycleview上实现向左滑动和向内移动Pinch。在recycleview上实现（滑动和捏合）触摸侦听器之后。它表现得很奇怪。大多数时候onFling（）方法都有e1 = null。即便捏也不那么完美。在捏的时候，它主要是滚动和捏不起作用。这是我的代码：

   mScaleDetector = new ScaleGestureDetector(getActivity(), new ScaleListener());
    mGestureDetector = new GestureDetector(getActivity(), new GestureListener());

recycleview.setOnTouchListener((v, event) -> {

 if (mGestureDetector.onTouchEvent(event)) {

        return false;
 } else if (mScaleDetector.onTouchEvent(event)) {

        return false;
}
      return true;

    });

 private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
    private float mScaleFactor = 1.0f;

    @Override
    public boolean onScale(ScaleGestureDetector detector) {
      super.onScale(detector);
      mScaleFactor = detector.getScaleFactor();
      return true;
    }

    @Override
    public boolean onScaleBegin(ScaleGestureDetector detector) {
      super.onScaleBegin(detector);
      return true;
    }

    @Override
    public void onScaleEnd(ScaleGestureDetector detector) {
      super.onScaleEnd(detector);
      if (mScaleFactor > 1) {
        //Toast.makeText("Zooming Out");
      } else if (mScaleFactor < 1) {
        //((AllShowsFragmentView) mContext).pinchInward();
        //Toast.makeText("Zooming In");
        moveToHomeScreen();
      }

    }
  }

  private class GestureListener extends GestureDetector.SimpleOnGestureListener {

  private static final int SWIPE_THRESHOLD = 100;
  private static final int SWIPE_VELOCITY_THRESHOLD = 100;
  protected MotionEvent mLastOnDownEvent = null;

  /*  @Override
    public boolean onSingleTapUp(MotionEvent e)
    {
      //single tap returns true so we know to register it over a swipe
      //onSingleTap();
      return false;
    }*/


    @Override
    public boolean onSingleTapConfirmed(MotionEvent e) {
      //onSingleTap();
      return super.onSingleTapConfirmed(e);
    }

    @Override
    public boolean onDown(MotionEvent e) {
      mLastOnDownEvent = e;
      return true;
    }

    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
      boolean result = false;
      try {
        if (e1==null)
          e1 = mLastOnDownEvent;
        if (e1==null || e2==null)
          return false;
        float diffY = e2.getY() - e1.getY();
        float diffX = e2.getX() - e1.getX();
        if (Math.abs(diffX) > Math.abs(diffY)) {
          if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
            if (diffX > 0) {
              //onSwipeRight();
            } else {
              //onSwipeLeft();
              moveToHomeScreen();
            }
            result = false;
          }
        } else if (Math.abs(diffY) > SWIPE_THRESHOLD
            && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
          if (diffY > 0) {
            //onSwipeBottom();
          } else {
            //onSwipeTop();
          }
          result = false;
        }
      } catch (Exception exception) {
        exception.printStackTrace();
      }
      return result;
    }
  }

Answer 1

试试ItemTouchHelper。它运作顺畅。

向左滑动，在recycleview（gridview）上向内捏

1 个答案: