提问者:小点点

手势检测器检测GridView项上的双击


注:此具体问题已解决,但存在严重的后续问题。查看GestureDetector-在GridView项目中双击Detect,但在onTouchEvent()中返回false

我想检测图像的< code>GridView中不同项目的双击。因此,我为适配器的< code>getView()方法中的每个项目< code>imageView分配了一个单独的< code>OnTouchListener。< code>gestureDetector是adapter-class的成员变量。

private GestureDetectorCompat gestureDetector;

public ImageGridViewAdapter(Context c, ArrayList<UriWrapper> startUpImages)     {
    mContext = c;
    uriManager  = new UriManager(startUpImages);
    gestureDetector = new GestureDetectorCompat(mContext, new SingleTapConfirm());
}

public View getView(final int position, View recycled, ViewGroup parent) {

    ViewHolder holder;
    if (recycled == null) {
       ..... find items by id
    } else{
        holder = (ViewHolder) recycled.getTag();
    }

    // Set listener to item image
    holder.image.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            // Always returns false, the gestureDetector does not detect anything
            boolean ret = gestureDetector.onTouchEvent(event);
            // At least the onTouch-callback gets called with the correct position
            Log.e(TAG, "onTouch returned " + ret + " at position " + position);
            return true;
        }
    });

    // Use glide library to load images into the image views
    Glide.with(mContext)....into(holder.image);
    return recycled;
}

私有类SingleTapConfirm扩展了GestureDetector。SimpleOnGestureListener(简单手势侦听器){

    @Override
    public boolean onSingleTapConfirmed(MotionEvent event) {
        Log.e(TAG, "onSingleTapConfirmed"); // never called..
        return true;
    }

    @Override
    public boolean onDoubleTap(MotionEvent e) {
        Log.e(TAG, "onDoubleTap"); // never called..
        return super.onDoubleTap(e);
    }
}

< code>OnTouchListener的工作,并在正确的位置被调用。然而,无论我做什么,都不会调用< code>GestureDetector的方法。这段代码似乎有什么问题?

更新:onTouch回调需要返回true,现在至少GestureDetector可以工作了。但是,返回true会破坏其余功能,因为我的GridView有一个长单击选择模式和一个全局OnTouchListener。

第二次更新:合并特定于项目的OnTouchListener和全局OnTouchListener不能正常工作。(只在某些项目上识别滑动手势)我希望我可以通过创建一个扩展ImageView的自定义视图并将特定于项目的视图分配给TouchListener来解决这两个问题。


共1个答案

匿名用户

 private GestureDetectorCompat gestureDetector;

    // in your adapter constructor
    gestureDetector = new GestureDetector(context, new SingleTapConfirm());

    public View getView(final int position, View recycled, ViewGroup parent) {

        ViewHolder holder;
        if (recycled == null) {
            .....find items by id
        } else {
            holder = (ViewHolder) recycled.getTag();
        }

        // Set listener to item image
        holder.image.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                // Use lazy initialization for the gestureDetector
                gestureDetector.onTouchEvent(event);
                // At least the onTouch-callback gets called with the correct position
                return true;
            }
        });

        // Use glide library to load images into the image views
        Glide.with(mContext)....into(holder.image);
        return recycled;
    }

    private class SingleTapConfirm extends GestureDetector.SimpleOnGestureListener {

        @Override
        public boolean onSingleTapConfirmed(MotionEvent event) {
            Log.e(TAG, "onSingleTapConfirmed"); // never called..
            return true;
        }

        @Override
        public boolean onDoubleTap(MotionEvent e) {
            Log.e(TAG, "onDoubleTap"); // never called..
            return super.onDoubleTap(e);
        }
    }

更新:

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