java - recyclerview-selection 如何监听 onSelectionEnter 事件和 onSelectionExit 事件

Question

我使用以下方法来使用 recyclerview-selection:

selectionTracker = new SelectionTracker.Builder<>("lazy-load-img-list-selection", this.recyclerView, new KeyProvider(1), new Lookup(), StorageStrategy.createLongStorage()).build();

我期待

selectionTracker.setOnSelectionEnter
selectionTracker.setOnSelectionExit

切换按钮“删除选择”“清除选择”可见性

怎么办？

更新:

我可以检测选择状态回收器适配器#onBindViewHolder，但这不是好方法，当确定 onSelectionExit 时，我必须检测每个渲染每个项目的所有项目状态

Answer 1

我找到解决方案:

  selectionTracker.addObserver(new SelectionTracker.SelectionObserver() {
        @Override
        public void onItemStateChanged(@NonNull Object key, boolean selected) {
            super.onItemStateChanged(key, selected);
            Selection selection = selectionTracker.getSelection();
            if (selected && selection.size() == 1) {
                if (onSelectionEnter != null) {
                    onSelectionEnter.run();
                }
            } else if (!selected && selection.size() == 0) {
                if (onSelectionExit != null) {
                    onSelectionExit.run();
                }
            }
        }
    });