Android OnCreateOptionsMenu() 未在 Fragment 中调用

OnCreateOptionsMenu() not called in Fragment

提问by Android_programmer_office

I have an app which got one activity with 2 fragments placed horizontally.

我有一个应用程序，它有一个活动，其中 2 个片段水平放置。

In my activity I inflated menu using onCreateOptionsMenu()using which I am able to display actionbar options menu. But when I try to update the action bar menu items from one of my fragment, the onCreateoptionsmenu()is not called. So, I'm not able to update the action bar options menu.

在我的活动中，我onCreateOptionsMenu()使用它来膨胀菜单，我可以使用它来显示操作栏选项菜单。但是，当我尝试从我的片段之一更新操作栏菜单项时，onCreateoptionsmenu()不会调用 。所以，我无法更新操作栏选项菜单。

The code in my activity is as below:

我的活动中的代码如下：

myActivity.java

我的活动.java

package com.andr.androidtablelist;

import java.io.IOException;

import android.app.ActionBar;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.Toast;

import com.andr.fragments.ListLeftFragment;
import com.andr.utils.DBHelper;

      public class TabletActivity extends Activity {
    ActionBar actionBar = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        DBHelper dbhelper;
        dbhelper = new DBHelper(this);
        try {
            dbhelper.createDatabase();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        setContentView(R.layout.activity_tablet);
        actionBar = getActionBar();
        actionBar.setDisplayHomeAsUpEnabled(false);
        getFragmentManager().beginTransaction()
                .replace(R.id.master, ListLeftFragment.newInstance()).commit();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.tablet, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case android.R.id.home:
            Toast.makeText(
                    getApplicationContext(),
                    "Back Stack Count::"
                            + getFragmentManager().getBackStackEntryCount(),
                    Toast.LENGTH_LONG).show();
            if (getFragmentManager().getBackStackEntryCount() == 1) {
                actionBar.setDisplayHomeAsUpEnabled(false);
            }
            if (getFragmentManager().getBackStackEntryCount() > 1) {
                getFragmentManager().popBackStack();

            }
            return true;

        }
        return super.onOptionsItemSelected(item);
    }

}
      // http://www.vogella.com/articles/AndroidListView/article.html

myFragment.java

myFragment.java

      package com.andr.fragments;


import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import android.app.Fragment;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.TextView;

import com.andr.androidtablelist.R;
import com.andr.helper.LazyHelper;

   public class ListLeftFragment extends Fragment{
    private static ListLeftFragment listFragment = null;

    public static ListLeftFragment newInstance(){
        listFragment = new ListLeftFragment();      
        return listFragment;
    }

     @Override
    public void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);


    }

     @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
         View v =  inflater.inflate(R.layout.fragment_listlayout, container,false);
         getActivity().invalidateOptionsMenu();
         ListView lv = (ListView)v.findViewById(R.id.lview);
         String[] values = new String[] { "Android", "iPhone", "WindowsMobile",
                    "Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X",
                    "Linux", "OS/2", "Ubuntu", "Windows7", "Max OS X", "Linux",
                    "OS/2", "Ubuntu", "Windows7", "Max OS X", "Linux", "OS/2",
                    "Android", "iPhone", "WindowsMobile" };
         getActivity().getActionBar().setTitle("LeftList");

          ArrayList<String> list = new ArrayList<String>();
         LazyHelper lHelper = new LazyHelper(getActivity());
         list = lHelper.getLazyDetials();

           /* for (int i = 0; i < values.length; ++i) {
              list.add(values[i]);
            }
            final StableArrayAdapter adapter = new StableArrayAdapter(getActivity(),
                android.R.layout.simple_list_item_1, list);*/
            LeftListAdapter lAdapter = new LeftListAdapter(getActivity(),list);
            lv.setAdapter(lAdapter);
            lv.setOnItemClickListener(new OnItemClickListener()
            {

                @Override
                public void onItemClick(AdapterView<?> arg0, View arg1,
                        int pos, long arg3) {
                    final String clickedData = (String)arg0.getItemAtPosition(pos);
                    Bundle bundle = new Bundle();
                    bundle.putString("clickedItemName", clickedData);
                    Fragment detailFragment = DetailFormRightFragment.newInstance();
                    detailFragment.setArguments(bundle);
                    getActivity().getFragmentManager().beginTransaction().replace(R.id.details, detailFragment).addToBackStack(null).commit();
                }

            }
                    );
         return v;
    }


     @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        super.onCreateOptionsMenu(menu, inflater);
        getActivity().getMenuInflater().inflate(R.menu.search, menu);
        SearchView searchView=(SearchView)menu.findItem(R.id.search);
        searchView.setIconifiedByDefault(true);
    } 

     @Override
    public boolean onOptionsItemSelected(MenuItem item) {

         super.onOptionsItemSelected(item);
         return false;
    }


     @Override
    public void onPrepareOptionsMenu(Menu menu) {
         super.onPrepareOptionsMenu(menu);
        /*MenuItem item;
        menu.clear();
        getActivity().getMenuInflater().inflate(R.menu.search, menu);
        SearchView searchView=(SearchView)menu.findItem(R.id.search);
        searchView.setIconifiedByDefault(true);*/
    }

     private class StableArrayAdapter extends ArrayAdapter<String> {

            HashMap<String, Integer> mIdMap = new HashMap<String, Integer>();

            public StableArrayAdapter(Context context, int textViewResourceId,
                List<String> objects) {
              super(context, textViewResourceId, objects);
              for (int i = 0; i < objects.size(); ++i) {
                mIdMap.put(objects.get(i), i);
              }
            }

            @Override
            public long getItemId(int position) {
              String item = getItem(position);
              return mIdMap.get(item);
            }

            @Override
            public boolean hasStableIds() {
              return true;
            }

          }

     private class LeftListAdapter extends BaseAdapter implements OnClickListener {
         private Context mcontext;
         ArrayList<String> listData;
         private  LayoutInflater inflater=null;
         public LeftListAdapter(Context context, ArrayList<String> listItems) {
              mcontext=context;
              listData=listItems;
              inflater = (LayoutInflater)mcontext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
         }

        @Override
        public int getCount() {
            return listData.size();
        }

        @Override
        public Object getItem(int arg0) {
            return null;
        }

        @Override
        public long getItemId(int arg0) {
            // TODO Auto-generated method stub
            return 0;
        }

        @Override
        public View getView(int position, View view, ViewGroup arg2) {
            // create a ViewHolder reference
            View vi=view;
            if(vi==null){
                vi = inflater.inflate(R.layout.item, null);
            }
            TextView text=(TextView)vi.findViewById(R.id.text);
            text.setText(listData.get(position));
            vi.setOnClickListener(this);
            return vi;
        }

        @Override
        public void onClick(View vi) {
            TextView text=(TextView)vi.findViewById(R.id.text);
            Bundle bundle = new Bundle();
            bundle.putString("clickedItemName", text.getText().toString());
            Fragment detailFragment = DetailFormRightFragment.newInstance();
            detailFragment.setArguments(bundle);
            getActivity().getFragmentManager().beginTransaction().replace(R.id.details, detailFragment).addToBackStack(null).commit();          
        }

     }
   }

回答by dangVarmit

In your fragment's onCreateView()method, you need to call setHasOptionsMenu(true)to tell the host activity that your fragment has menu options that it wants to add.

在您的片段的onCreateView()方法中，您需要调用setHasOptionsMenu(true)以告诉宿主活动您的片段具有要添加的菜单选项。

回答by animalize

If you are using a themethat does notsupport ActionBar, then OnCreateOptionsMenu() will not be called automatically, even you wrote all Java codes properly.

如果您使用的主题，它不支持动作条，然后OnCreateOptionsMenu（）将不会被自动调用，即使你正确地写所有的Java代码。

You can open AndroidManifest.xml, change the value of android:themeto "@android:style/Theme.Holo.Light.DarkActionBar", or any other themes that support ActionBar.

您可以打开 AndroidManifest.xml，将android:theme的值更改为“@android:style/Theme.Holo.Light.DarkActionBar”，或任何其他支持 ActionBar 的主题。

回答by Anisetti Nagendra

this worked for me

这对我有用

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    setHasOptionsMenu(true);
    View view = inflater.inflate(R.layout.sample, null);
}

回答by Hyman's medulla oblongata

Also, make sure that the Toolbar instance you're passing to

另外，请确保您传递给的 Toolbar 实例

setSupportActionBar(toolbar);

in your Activity is not null, because you won't get an exception if it is indeed nulland you will lose a couple of hours like I did.

在您的 Activity is not null，因为如果确实如此null，您将不会得到异常，并且您将像我一样失去几个小时。

I used ButterKnifeto bind the views, but accidentally placed setSupportActionBar(toolbar)before I actually made the call to ButterKnife.bind()

我使用ButterKnife绑定视图，但setSupportActionBar(toolbar)在我实际调用之前不小心放置了ButterKnife.bind()

回答by Ken Ratanachai S.

Simply tell the host activity that your fragment has options menu in its constructor.

只需告诉宿主活动您的片段在其构造函数中有选项菜单。

public YourFragment() {setHasOptionsMenu(true);}

public YourFragment() {setHasOptionsMenu(true);}

Although it worked for me, it is discouraged as noted in comment from @aldorain

虽然它对我有用，但正如@aldorain 的评论中所指出的那样不鼓励

Applications should generally not implement a constructor. The first place application code can run where the fragment is ready to be used is in onAttach(Activity), the point where the fragment is actually associated with its activity.

应用程序通常不应实现构造函数。应用程序代码可以在准备使用片段的地方运行的第一个位置是 onAttach(Activity)，片段实际与其活动相关联的点。

So put setHasOptionsMenu(true) in onCreateView() or onAttach() instead.

所以将 setHasOptionsMenu(true) 放在 onCreateView() 或 onAttach() 中。

回答by Nimisha Patel

Set setHasOptionsMenu(true)in onCreateView()method in fragment.

设置setHasOptionsMenu(true)在onCreateView()在片段的方法。

@Override

 public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) 
 {
    Viewroot=inflater.inflate(R.layout.fragment_client_requestfragment,container,false);
  hideKeyboard();
    getemail = getArguments().getString("email_id");
    Log.e("email_id from activity",getemail);
    setHasOptionsMenu(true);
    return root;
}