如果在Webview中有触摸事件，防止ViewPager拦截触摸事件

Question

我有一个显示Fragment页面的ViewPager。每个Fragment都是一个WebView，它们显示离线网站。其中一些webview具有javascript滑动事件以使其正常工作。

如果webview没有滑动事件（在javascript中），则希望实现这样的功能，触摸事件将传递给ViewPager，否则将被webview消耗。

我尝试重写ViewPagers。

@Override
public boolean onInterceptTouchEvent(MotionEvent event)
{
    return (this.swipeable) ? super.onInterceptTouchEvent(event) : false;
}

然而，这样做阻止了ViewPager的可滑动（预期效果），但也阻止了滑动事件传递到webview，因此我得到了两个不希望看到的结果。

是否有办法先将触摸事件传递给webView，如果在fragment中未被使用，则将其传回ViewPager？

如果我在MyViewPager中出现错误，代码如下：

public class MyViewPager extends ViewPager implements   GestureDetector.OnGestureListener
{
private static final String TAG = MyViewPager.class.getSimpleName();
private boolean swipeable = true;
private float lastX   = 0;
private long lastTime = 0 ;
private GestureDetector mGestureDetector;
private boolean mScrolling = false;

public MyViewPager(Context context) {
    super(context);
    mGestureDetector = new GestureDetector(context, this);
}

public MyViewPager(Context context, AttributeSet attrs) {
    super(context, attrs);
    mGestureDetector = new GestureDetector(context, this);
}

public void setSwipeable(boolean swipeable) {
    this.swipeable = swipeable;
}

@Override
public boolean onInterceptTouchEvent(MotionEvent event)
{

   /* float speed = 0;
    if(event.getAction() == MotionEvent.ACTION_MOVE)
    {
        if(lastX!=0) {
            speed = (event.getRawX()- lastX) / (System.currentTimeMillis()-lastTime);
            if(speed < 0.0 ){speed *=-1;}
            Log.e(TAG, "Move at speed ->"+speed);
            if(speed >0.5){return false;}
        }
        lastX    = event.getRawX();
        lastTime = System.currentTimeMillis();
        return true;
    }*/
  // return true;

    return (this.swipeable) ? super.onInterceptTouchEvent(event) : false;
}

@Override
public boolean onTouchEvent(MotionEvent event)
{
    Log.i(TAG, "onTouch event");
  //  mGestureDetector.onTouchEvent(event);
    return false;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velX, float velY) {
    Log.i(TAG, "flinging");
    return false;
}

@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distX, float distY)
{
    float displacement = distX;
    return false;
}

// Unused Gesture Detector functions below

@Override
public boolean onDown(MotionEvent event) {
    return false;
}

@Override
public void onLongPress(MotionEvent event) {
    // we don't want to do anything on a long press, though you should probably feed this to the page being long-pressed.
}

@Override
public void onShowPress(MotionEvent event) {
    // we don't want to show any visual feedback
}

@Override
public boolean onSingleTapUp(MotionEvent event) {
    // we don't want to snap to the next page on a tap so ignore this
    return false;
}

}

- Mark Gilchrist

Answer 1

我现在有两种解决这个问题的方法：一种是扩展一个ViewPager类并覆盖其中的部分内容。

public boolean onInterceptTouchEvent(MotionEvent event)
{
   // code  
}

然而，一种更好的解决方案是覆盖原有的

标签。

protected boolean canScroll(View v, boolean checkV, int dx, int x, int y) {
  return true;
}

为了完整起见，这里是整个类：

public class ZoltansViewPager extends ViewPager {

 private static final String TAG = ZoltansViewPager.class.getSimpleName();
 private boolean swipeable = true;
 private float lastX   = 0;
 private long lastTime = 0 ;
 private GestureDetector mGestureDetector;
 private boolean mScrolling = false;


 public ZoltansViewPager(Context context) {
    super(context);
 }

 public ZoltansViewPager(Context context, AttributeSet attrs) {
    super(context, attrs);
 }


 public void setSwipeable(boolean swipeable) {
    this.swipeable = swipeable;
 }

 @Override
 protected boolean canScroll(View v, boolean checkV, int dx, int x, int y) {
     Log.i(TAG , " boolean checkV ->"+checkV + ", int dx-> "+dx+", int x->"+x+", int y->"+y);
     if(x <300 || x >1700 ){return true;}
     return false;
 }
}

希望这能帮助其他人

- Mark Gilchrist