MultiChoiceModeListener永远不会调用

Question

我想选择多个项目并使用操作栏进行操作。我尝试了以下代码，但它无法正常工作

        listView = (ListView) findViewById(R.id.conversationList);
        ((ConversationsAdapter) conversationsAdapter).updateConversations(conversationsList);

        listView.setChoiceMode(AbsListView.CHOICE_MODE_MULTIPLE_MODAL);

        choiceModeListener = new AbsListView.MultiChoiceModeListener() {
            @Override
            public void onItemCheckedStateChanged(ActionMode actionMode, int i, long l, boolean b) {
                Toast.makeText(context,listView.getCheckedItemCount() ,Toast.LENGTH_SHORT).show();
            }

            @Override
            public boolean onCreateActionMode(ActionMode actionMode, Menu menu) {
                MenuInflater menuInflater = actionMode.getMenuInflater();
                menuInflater.inflate(R.menu.contextual_menu,menu);
                return false;
            }

            @Override
            public boolean onPrepareActionMode(ActionMode actionMode, Menu menu) {
                return false;
            }

            @Override
            public boolean onActionItemClicked(ActionMode actionMode, MenuItem menuItem) {
                return false;
            }

            @Override
            public void onDestroyActionMode(ActionMode actionMode) {

            }
        };
        listView.setMultiChoiceModeListener(choiceModeListener);



        listView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {
                Conversation item = (Conversation) conversationsAdapter.getItem(position);
                startChat(item, false);
            }
        });

不知道为什么，MultiChoiceModeListener永远不会打电话。问题是什么？ OnItemClickListener工作得非常好。