我第一次在GridView中拖放时丢失了ImageView

Question

我做了一个拖放GridView.除了第一次拖放外,一切都很完美.我无法找到它第一次发生的原因.

第一次将项目拖动到gridview中的其他项目时,项目的imageview源将丢失.当我放弃它时,源将被修复.之后,每件事都会正常工作.任何想法我如何解决这个或奇怪的行为的原因.欢迎各方面的帮助.

这是我的touchListener将处理拖放:

mGridView.setOnTouchListener(new View.OnTouchListener() {

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if (event.getAction() == MotionEvent.ACTION_DOWN) {
                GridView parent = (GridView) v;

                int x = (int) event.getX();
                int y = (int) event.getY();

                int position = parent.pointToPosition(x, y);
                if (position > AdapterView.INVALID_POSITION) {

                    int count = parent.getChildCount();
                    for (int i = 0; i < count; i++) {
                        View curr = parent.getChildAt(i);
                        curr.setOnDragListener(new View.OnDragListener() {

                            @Override
                            public boolean onDrag(View v, DragEvent event) {

                                boolean result = true;
                                int action = event.getAction();
                                switch (action) {
                                case DragEvent.ACTION_DRAG_STARTED:
                                    break;
                                case DragEvent.ACTION_DRAG_LOCATION:
                                    break;
                                case DragEvent.ACTION_DRAG_ENTERED:    
                                    setBlueFilterOnImageView((ImageView) v, getActivity());
                                    break;
                                case DragEvent.ACTION_DRAG_EXITED:
                                    clearColorFilterOnImageView((ImageView) v);
                                    break;
                                case DragEvent.ACTION_DROP:

                                    if (event.getLocalState() == v) {
                                        result = false;
                                    } else {

                                        View droped = (View) event.getLocalState();

                                        View target = v;

                                        app.myProfile().removeProfilePhotoAtIndex(((DragGridItemHolder) droped.getTag()).position);
                                        app.myProfile().insertProfilePhoto(((DragGridItemHolder) droped.getTag()).id, ((DragGridItemHolder) target.getTag()).position);


                                        mAdapter.notifyDataSetChanged();

                                    }
                                    break;
                                case DragEvent.ACTION_DRAG_ENDED:
                                    clearColorFilterOnImageView((ImageView) v);     
                                    break;
                                default:
                                    result = false;
                                    break;
                                }
                                return result;
                            }
                        });
                    }

                    int relativePosition = position - parent.getFirstVisiblePosition();


                    View target = (View) parent.getChildAt(relativePosition);

                    DragGridItemHolder holder = (DragGridItemHolder) target.getTag();
                    String text = holder.id;
                    ClipData data = ClipData.newPlainText("DragData", text);
                    target.startDrag(data, new View.DragShadowBuilder(target), target, 0);
                }
            }
            return false;
        }
    });

编辑

public static void setBlueFilterOnImageView(ImageView imageView, Context context){
    PorterDuffColorFilter blueFilter = new PorterDuffColorFilter(
            context.getResources().getColor(R.color.grid_state_focused),
            PorterDuff.Mode.SRC_ATOP);
    imageView.setColorFilter(blueFilter);
    imageView.setBackgroundColor(context.getResources().getColor(
            R.color.grid_state_pressed));
}

Answer 1

我终于找到了解决办法。所以问题是当我在 DragEvent.ACTION_DRAG_ENTERED 中设置颜色过滤器时，ImageView 源将会消失。为了避免这种情况，我在设置滤色器时重置了源。不是一个非常干净的解决方案，但它对我有用..感谢所有帮助