Android中的垂直和水平手势

Question

我希望我的GestureOverlayView可以检测纯粹的水平和垂直手势.

来自http://android-developers.blogspot.com/2009/10/gestures-on-android-16.html

"orientation"表示下方视图的滚动方向.在这种情况下,列表垂直滚动,这意味着任何水平手势(如action_delete)都可以立即被识别为手势.以垂直笔划开头的手势必须至少包含一个要识别的水平分量.换句话说,简单的垂直线不能被识别为手势,因为它会与列表的滚动冲突.

看起来像一个catch-22,如果android:orientation设置为vertical,我只能进行水平滑动,如果android:orientation设置为水平,我只能进行垂直滑动.我怎样才能解决这个问题？

Answer 1

我在黑客马拉松遇到了这个问题.使用GestureOverlayView无法解决问题,因此您必须使用运动事件.然而,GestureOverlayView可以使用稍微更"详细"的手势,就像圆圈一样.我注意到的是,GestureOverlayView最适合封闭的数字.那么,它就是motionEvent传感器.我在这里找到了代码.我修改了Gav对垂直滑动的回答.虽然没有测试过,但积极的认为应该有效.

这是一个例子:

public class SelectFilterActivity extends Activity implements OnClickListener
{

private static final int SWIPE_MIN_DISTANCE = 120;
private static final int SWIPE_MAX_OFF_PATH = 250;
private static final int SWIPE_THRESHOLD_VELOCITY = 200;
private GestureDetector gestureDetector;
View.OnTouchListener gestureListener;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    /* ... */

    // Gesture detection
    gestureDetector = new GestureDetector(new MyGestureDetector());
    gestureListener = new View.OnTouchListener() {
        public boolean onTouch(View v, MotionEvent event) {
            return gestureDetector.onTouchEvent(event);
        }
    };

}

class MyGestureDetector extends SimpleOnGestureListener {
    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
        try {
            // downward swipe
            if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH && Math.abs(velocityY) > SWIPE_THRESHOLD_VELOCITY)
                Toast.makeText(SelectFilterActivity.this, "Downward Swipe", Toast.LENGTH_SHORT).show();
 else if (Math.abs(e2.getY() - e1.getY()) > SWIPE_MAX_OFF_PATH && Math.abs(velocityY) > SWIPE_THRESHOLD_VELOCITY)
                Toast.makeText(SelectFilterActivity.this, "Upward Swipe", Toast.LENGTH_SHORT).show();
            // right to left swipe
            else if(e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
                Toast.makeText(SelectFilterActivity.this, "Left Swipe", Toast.LENGTH_SHORT).show();
            }  else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
                Toast.makeText(SelectFilterActivity.this, "Right Swipe", Toast.LENGTH_SHORT).show();
            }
        } catch (Exception e) {
            // nothing
        }
        return false;
    }

}

现在将其添加到您想要手势检测的视图中,

// Do this for each view added to the grid
    imageView.setOnClickListener(SelectFilterActivity.this); 
    imageView.setOnTouchListener(gestureListener);

欢呼加密为代码!

Answer 2

所有你需要做的,是将GestureStrokeAngleThreshold设置为接近90的值(我使用90f)

角度threashold的默认值是40.0f,因为您将跳过简单的垂直手势