如何处理Android WebView忽略的滑动?

时间:2015-05-13 00:14:46

标签: android webview gesturedetector

我有一个Android应用程序,它是Web视图中的全部。当用户在应用程序的背景上滑动而不是滑块或按钮时,我想抓住。

我尝试将GestureDetector附加到WebView,但是它捕获了所有滑动,包括WebView中控件的滑动。我怎样才能抓住背景滑动?

1 个答案:

答案 0 :(得分:0)

在阅读了许多答案之后,我终于想出了一个简单的解决方案。

1-为您的操作创建一个简单的界面:

public interface TouchListener  {
    default void onSwipeLeft() {
        Logger.d( "Swipe left");
    }
    default void onSwipeRight() {
        Logger.d( "Swipe right");
    }
}

2-创建一个简单的OnTouchListener:

public class OnSwipeWebviewTouchListener implements View.OnTouchListener {
    private final GestureDetector gestureDetector;
    public OnSwipeWebviewTouchListener(Context ctx, TouchListener touchListener) {
        gestureDetector = new GestureDetector(ctx, new GestureListener(touchListener));
    }
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return gestureDetector.onTouchEvent(event);
    }
    private final class GestureListener extends GestureDetector.SimpleOnGestureListener {
        private TouchListener touchListener;
        GestureListener(TouchListener touchListener) {
            super();
            this.touchListener = touchListener;
        }
        @Override
        public boolean onDown(MotionEvent e) {
            return false;  // THIS does the trick
        }
        @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)) {
                    // You can customize these settings, so 30 is an example
                    if (Math.abs(diffX) > 30 && Math.abs(velocityX) > 30) {
                        if (diffX > 0) {
                            touchListener.onSwipeRight();
                        } else {
                            touchListener.onSwipeLeft();
                        }
                        result = true;
                    }
                } else {
                    result = false;
                }
            } catch (Exception exception) {
                exception.printStackTrace();
            }
            return result;
        }
    }
}

3-将它们简单地连接在一起:

webView.setOnTouchListener( new OnSwipeWebviewTouchListener( getActivity(), this));