我正在尝试ShareActionProvider
在片段中的上下文操作栏中使用支持库来实现.我在正常的操作栏(onCreateOptionsMenu())中没有遇到任何问题,但是当我在CAB(MultiModeListener
接口中的onCreateActionMode())中尝试它时,我收到错误:
getActionProvider: item does not implement SupportMenuItem; returning null
通过https://cells-source.cs.columbia.edu/plugins/gitiles/platform/frameworks/support/+/30837f1095c803f332f4a1c3f0917c8afdd50156/v4/java/android/support/v4/view/MenuItemCompat.java查看Android源代码,问题似乎是因为我MenuItem
不是以下的实例SupportMenuItem
:
public static ActionProvider getActionProvider(MenuItem item) { if (item instanceof SupportMenuItem) { return ((SupportMenuItem) item).getSupportActionProvider(); } // TODO Wrap the framework ActionProvider and return it Log.w(TAG, "getActionProvider: item does not implement SupportMenuItem; returning null"); return null; }
关于如何解决这个问题的任何想法?
清单:
活动:
import android.os.Bundle; import android.support.v7.app.ActionBarActivity; public class myactivity_ActionBarActivity extends ActionBarActivity{ @Override public void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.actionbaractivity_layout); //loads a fragment } }
片段:
import android.support.v7.widget.ShareActionProvider; import android.support.v4.view.MenuItemCompat; import android.view.MenuItem; import android.view.Menu; import android.support.v4.app.Fragment; ... ... @Override public void onActivityCreated(Bundle savedInstanceState) { ... ... //Handle Action mode events myListView.setMultiChoiceModeListener(new MultiChoiceModeListener() { private ShareActionProvider mShareActonProvider; .... .... @Override public boolean onCreateActionMode(ActionMode mode, Menu menu) { MenuInflater inflater = mode.getMenuInflater(); inflater.inflate(R.menu.chatsession_contextmenu, menu); //get the ShareActionProvider from the menu item MenuItem item = menu.findItem(R.id.share_menu); mShareActonProvider = (ShareActionProvider) MenuItemCompat.getActionProvider(item); return true; } } ... ... }
菜单布局文件:
编辑1:
问题的根源似乎Menu
是作为参数传递给onCreateActionMode(ActionMode mode, Menu menu)
和的对象的差异onCreateOptionsMenu(Menu menu, MenuInflater inflater)
.只有一个人才onCreateOptionsMenu
有MenuWrapperICS
.以下是调试模式下两个对象的屏幕截图:
onCreateActionMode(ActionMode mode, Menu menu) :
onCreateOptionsMenu(Menu menu, MenuInflater inflater) :
问题是MultipleModeListener
界面扩展了android.view.ActionMode.Callback
,如http://androidxref.com/4.4.2_r2/xref/frameworks/base/core/java/android/widget/AbsListView.java#6301中的源代码所示.如果您使用ShareActionProvider
支持库,则需要使用支持库android.support.v7.view.ActionMode.Callback
.
解决方案是创建自己的ActionMode.CallBack实现,而不是使用框架MultipleModeListener
.这样,您可以确保在需要的地方使用支持库.
例如 :
导入的V7版本ActionMode
,并ActionBarActivity
在您的片段
import android.support.v7.view.ActionMode; import android.support.v7.app.ActionBarActivity;
onClickListener
为列表视图创建一个并用于startSupportActionMode
启动自定义ActionMode.CallBack
实现
myListView.setItemsCanFocus(false); myListView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE); actionMode = null; myListView.setOnItemClickListener(new OnItemClickListener(){ @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id){ if(myListView.getCheckedItemCount() == 0){ actionMode.finish(); return; } if(actionMode == null){ actionMode = ((ActionBarActivity)getActivity()).startSupportActionMode(new ContextualActionBar()); } } });
创建自定义ActionMode.Callback
实现
private class ContextualActionBar implements ActionMode.Callback{ private ShareActionProvider mShareActionProvider; @Override public boolean onActionItemClicked(ActionMode mode, MenuItem item) { switch(item.getItemId()){ case R.id.share_menu : mode.finish(); return true; default : return false; } } @Override public boolean onCreateActionMode(ActionMode mode, Menu menu) { MenuInflater inflater = mode.getMenuInflater(); inflater.inflate(R.menu.chatsession_contextmenu, menu); //Initialize the ShareActionProvider MenuItem shareMenuItem = menu.findItem(R.id.share_menu); mShareActionProvider = (ShareActionProvider) MenuItemCompat.getActionProvider(shareMenuItem); Intent shareIntent = new Intent(Intent.ACTION_SEND); shareIntent.setType("text/plain"); shareIntent.putExtra(Intent.EXTRA_TEXT, "test message"); mShareActionProvider.setShareIntent(shareIntent); return true; } @Override public void onDestroyActionMode(ActionMode mode) { //Nullify the actionMode object //so that the onClickListener can identify whether the ActionMode is ON actionMode = null; //Uncheck all checked messages SparseBooleanArray selectedItems = myListView.getCheckedItemPositions(); for(int i=0;i<selectedItems.size();i++){ myListView.setItemChecked(selectedItems.keyAt(i), false); } } @Override public boolean onPrepareActionMode(ActionMode arg0, Menu arg1) { // TODO Auto-generated method stub return false; } }