invalidateOptionsMenu不会从片段调用

Question

我有一个片段,需要建立自己的操作栏:

public class CalendarFragment extends Fragment {

public CalendarFragment() {
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    getActivity().supportInvalidateOptionsMenu();
    setHasOptionsMenu(true);
}

@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
    inflater.inflate(R.menu.calendar_menu1, menu);
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    return super.onOptionsItemSelected(item);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    TextView textView = new TextView(getActivity());
    textView.setGravity(Gravity.CENTER);
    textView.setText("Calendar Fragment");
    return textView;
}

}

问题是它没有创建一个包含来自calendar_menu1的项目的新菜单,只是将其中的项目添加到旧菜单,就像invalidateOptionsMenu不起作用(我也试过getActivity().invalidateOptionsMenu())

Answer 1

你必须调用onCreate():

setHasOptionsMenu(true);

Answer 2

这是正常的，查看MenuInflater的 javadoc ，“项目和子菜单将添加到此菜单中”：

public void inflate (int menuRes, Menu menu) 
Inflate a menu hierarchy from the specified XML resource. Throws InflateException if there is an error.

Parameters
menuRes  Resource ID for an XML layout resource to load (e.g., R.menu.main_activity) 
menu  The Menu to inflate into. The items and submenus will be added to this Menu. 

您之前是否尝试过调用menu.clear()来膨胀您的片段菜单？

@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
    menu.clear();
    inflater.inflate(R.menu.calendar_menu1, menu);
}