Question

我有一个gridview，其中包含与其他视图的相对布局。我想向其中添加滑动功能，如下所示：

scrollView.setOnTouchListener(new OnSwipeTouchListener(this) {
        public void onSwipeRight() {
            //some action
        }

        public void onSwipeLeft() {
           //some action
        }
    });

这是OnSwipeTouchListener类代码：

public class OnSwipeTouchListener implements View.OnTouchListener {

private final GestureDetector gestureDetector;

public OnSwipeTouchListener (Context ctx){
    gestureDetector = new GestureDetector(ctx, new GestureListener());
}

@Override
public boolean onTouch(View v, MotionEvent event) {
    return gestureDetector.onTouchEvent(event);
}

private final class GestureListener extends GestureDetector.SimpleOnGestureListener {

    private static final int SWIPE_THRESHOLD = 60;
    private static final int SWIPE_VELOCITY_THRESHOLD = 60;

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

    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
        boolean result = false;
        try {
            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();
                }
                result = true;
            }
            else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                if (diffY > 0) onSwipeBottom();
                else onSwipeTop();
            }
            result = true;

        }
        catch (Exception exception) {
            exception.printStackTrace();
        }
        return result;
    }
}

public void onSwipeRight() {}
public void onSwipeLeft() {}
public void onSwipeTop() {}
public void onSwipeBottom() {}
}

但我在android studio中收到此警告：

Custom view `ScrollView` has setOnTouchListener called on it but does not override performClick less... (Ctrl+F1)

如果覆盖onTouchEvent或使用OnTouchListener的View也未实现performClick并在检测到点击时调用它，则该View可能无法正确处理可访问性操作。理想情况下，应该将处理点击动作的逻辑放在View＃performClick中，因为某些可访问性服务会在发生点击动作时调用performClick。

运行该应用程序时，不会处理任何滑动事件。如何正确检测滑动并根据滑动方向执行操作？谢谢。

ScrollView没有使用自定义SwipeTouchListener

0 个答案: