我工作的一个应用程序，它使用许多网页刷卡通过，但是在一些网页，我想能够prevent滚动到下一个页面，直到他们已经选择了一些东西。

I'm working on an app which uses many pages to swipe through, however at some pages I would like to be able to prevent scrolling to the next page until they've selected something.

目前，我已经扩展ViewPager：

At the moment I've extended ViewPager:

/* (non-Javadoc)
 * @see android.support.v4.view.ViewPager#onInterceptTouchEvent(android.view.MotionEvent)
 */
@Override
public boolean onInterceptTouchEvent(MotionEvent event) {
    if (this.canGoLeft || this.canGoRight) {
        return super.onInterceptTouchEvent(event);
    }

    return false;
}

/* (non-Javadoc)
 * @see android.support.v4.view.ViewPager#onTouchEvent(android.view.MotionEvent)
 */
@Override
public boolean onTouchEvent(MotionEvent ev) {
    boolean lockScroll = false;
    switch (ev.getAction()) {
    case MotionEvent.ACTION_DOWN:
        lastX = ev.getX();
        lockScroll = false;
        return super.onTouchEvent(ev);
    case MotionEvent.ACTION_MOVE:
        if (canGoLeft && lastX < ev.getX()) {
            lockScroll = false;
        } else if (canGoRight && lastX > ev.getX()) {
            lockScroll = false;
        } else {
            lockScroll = true;
        }


        lastX = ev.getX();

        break;
    }

    lastX = ev.getX();

    if (lockScroll) {
        //make callback to prevent movement
        if (mOnPreventCallback != null) {
            mOnPreventCallback.onPreventMovement();
        }
        return false;
    } else {
        return super.onTouchEvent(ev);
    }
}

注：我试图实现prevent刷卡，以previous但我仍然可以刷卡，以previous但你需要在最远处左侧刷卡和刷了一下。它的喜怒无常，但它不prevent刷卡完全

Note: I've tried to implement prevent swiping to previous but I can still swipe to previous but you need to swipe from the uttermost left side and swipe a bit. It's temperamental but it does not prevent swiping completely.

3的事情我想在这里做的：

3 things I want to do here:

谁能帮我？

在此先感谢！

推荐答案

当我遇到了类似的问题，我做了我自己的监听器有gestureDetector，并使它不响应刷卡不惜一切，你可以很容易地调整到不响应只有在某些条件下刷卡的权利。这应该回答你的号码1和2。

When I faced a similar problem, I made my own Listener with a gestureDetector and made it not respond to swiping at all, you can easily adjust it to not respond to swiping to the right only under some condition. This should answer your numbers 1 and 2.

这是监听器：

public class OnSwipeTouchListener implements OnTouchListener {

@SuppressWarnings("deprecation")
private final GestureDetector gestureDetector = new GestureDetector(new GestureListener());

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

private final class GestureListener extends SimpleOnGestureListener {

    private static final int SWIPE_THRESHOLD = 100;
    private static final int SWIPE_VELOCITY_THRESHOLD = 100;

    @Override
    public boolean onDown(MotionEvent e) {
        return true;
    }
    @Override
    public boolean onSingleTapConfirmed(MotionEvent e) {
        onTouch(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();
                    }
                }
            } else {
               // onTouch(e);
            }
        } catch (Exception exception) {
            exception.printStackTrace();
        }
        return result;
    }
}
public void onTouch(MotionEvent e) {
}
public void onSwipeRight() {
//call this only if your condition was set
}

public void onSwipeLeft() {
//nothing, this means,swipes to left will be ignored
}

public void onSwipeTop() {
}

public void onSwipeBottom() {
}
}

这是使用的例子：

and this is an example of use :

viewPager.setOnTouchListener(new OnSwipeTouchListener() {
public void onSwipeRight() {
  if(your conditionIsMet){
// move your pager view to the right
     }
   }

});

有可能是一个更简单，更优雅的解决方案，但这个工作很适合我。

There might be a simpler and more elegant solution, but this worked well for me.