android - 在 Android 中发生 OnClickEvent 时激活 CAB 菜单

Question

单击 ActionBar 中的 MenuItem 时尝试激活 CAB 菜单。下面是我如何设置 GridView 来收听 Multi Choice。当我长按 GridView 中的任何项目时，multiModeChoiceListener 工作正常。它工作正常。现在我需要在按下操作栏中的菜单项时激活 CAB 菜单。按下后，CAB 菜单应显示已选择 0 个项目。之后，它应该允许我通过单击从 GridView 中选择项目。我怎样才能实现这个功能？

GridView 设置监听器:

gv.setChoiceMode(GridView.CHOICE_MODE_MULTIPLE_MODAL); 
gv.setMultiChoiceModeListener(new MultiChoiceModeListener());

MultiChoiceModeListener.java

public class MultiChoiceModeListener implements
    GridView.MultiChoiceModeListener {  

public boolean onCreateActionMode(ActionMode mode, Menu menu) {
    mode.getMenuInflater().inflate(R.menu.featured_multiselect, menu);
    MenuItem mi = menu.findItem(R.id.close);
    mi.setIcon(R.drawable.cancel);
    mode.setTitle("Select Items");
    return true;
}

public boolean onPrepareActionMode(ActionMode mode, Menu menu) {    
    return true;
}

public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
    Toast.makeText(getApplicationContext(), item.getTitle(),
            Toast.LENGTH_SHORT).show();
    if (item.getTitle().toString().equalsIgnoreCase("Close")) {
        mode.finish();
    }
    return true;
}

public void onDestroyActionMode(ActionMode mode) {
    new ChangeNotifier().changeOnFavoriteStore = true;
    new AddFavorites().execute("add", device_id, dataArray);
    if (notify == true) {
        Toast.makeText(getApplicationContext(),
                "Selected items are added to Favorites",
                Toast.LENGTH_SHORT).show();
        notify = false;
    }
}

public void onItemCheckedStateChanged(ActionMode mode, int position,
        long id, boolean checked) {
    int selectCount = gridView.getCheckedItemCount();
    if (selectCount > 0) {
        notify = true;              
        dataArray.add(position);
        switch (selectCount) {
        case 1:
            mode.setSubtitle("One item added to favorites");
            break;
        default:
            mode.setSubtitle("" + selectCount
                    + " items added to favorites");
            break;
        }
    } 

   }

OnMenuItemClick 方法:

 public boolean onPrepareOptionsMenu(final Menu menu) {

    final MenuItem editItem = menu.findItem(R.id.editit);

    editItem.setOnMenuItemClickListener(new OnMenuItemClickListener() {

        @Override
        public boolean onMenuItemClick(MenuItem item) {
            //the CAB menu should be activated here. So that it reads that 0 items are selected in ActionBar

            return false;
        }

    });

Answer 1

根据您的问题，我了解到您正在尝试通过单击其中一个菜单项来启动与 GridView 关联的 CAB。我不知道你是否可以这样做(但我可能会弄错)，因为 MultiChoiceModeListener 需要检查一个项目才能开始。根据您的布局和 GridView 的整体外观，我认为您可以在 GridView(没有内容显示)并使用 setItemChecked(dummyItemPosition, true) 启动 GridView CAB。当然，您需要有额外的逻辑来处理 MultiChoiceModeListener 中的额外项目:

 public void onItemCheckedStateChanged(ActionMode mode, int position,
        long id, boolean checked) {
    if (position == theDummyPosition)
         return; // so we start the CAB but there aren't any items checked
    }
    int selectCount = gridView.getCheckedItemCount();
    if (selectCount > 0) {
        notify = true;              
        dataArray.add(position);
        // if you select another item you'll have two selected items(because of the dummy item) so you need to take care of it 
        switch (selectCount) {
        case 1:
            mode.setSubtitle("One item added to favorites");
            break;
        default:
            mode.setSubtitle("" + selectCount
                    + " items added to favorites");
            break;
        }
    } 

   }

上面的解决方案是一个 hack，很可能丢失 MultiChoiceModeListener 并简单地启动一个您可以在两种情况下都可以操作的 ActionMode 会容易得多。