Home | History | Annotate | Download | only in app 
      1 /*
      2  * Copyright (C) 2010 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.example.android.apis.app;
     18 
     19 import com.example.android.apis.R;
     20 
     21 import android.app.Activity;
     22 import android.app.Fragment;
     23 import android.app.FragmentManager;
     24 import android.app.FragmentTransaction;
     25 import android.os.Bundle;
     26 import android.view.Menu;
     27 import android.view.MenuInflater;
     28 import android.view.MenuItem;
     29 import android.view.View;
     30 import android.view.View.OnClickListener;
     31 import android.widget.CheckBox;
     32 
     33 /**
     34  * Demonstrates how fragments can participate in the options menu.
     35  */
     36 public class FragmentMenu extends Activity {
     37     Fragment mFragment1;
     38     Fragment mFragment2;
     39     CheckBox mCheckBox1;
     40     CheckBox mCheckBox2;
     41 
     42     // Update fragment visibility when check boxes are changed.
     43     final OnClickListener mClickListener = new OnClickListener() {
     44         public void onClick(View v) {
     45             updateFragmentVisibility();
     46         }
     47     };
     48 
     49     @Override
     50     protected void onCreate(Bundle savedInstanceState) {
     51         super.onCreate(savedInstanceState);
     52         setContentView(R.layout.fragment_menu);
     53 
     54         // Make sure the two menu fragments are created.
     55         FragmentManager fm = getFragmentManager();
     56         FragmentTransaction ft = fm.beginTransaction();
     57         mFragment1 = fm.findFragmentByTag("f1");
     58         if (mFragment1 == null) {
     59             mFragment1 = new MenuFragment();
     60             ft.add(mFragment1, "f1");
     61         }
     62         mFragment2 = fm.findFragmentByTag("f2");
     63         if (mFragment2 == null) {
     64             mFragment2 = new Menu2Fragment();
     65             ft.add(mFragment2, "f2");
     66         }
     67         ft.commit();
     68 
     69         // Watch check box clicks.
     70         mCheckBox1 = (CheckBox)findViewById(R.id.menu1);
     71         mCheckBox1.setOnClickListener(mClickListener);
     72         mCheckBox2 = (CheckBox)findViewById(R.id.menu2);
     73         mCheckBox2.setOnClickListener(mClickListener);
     74 
     75         // Make sure fragments start out with correct visibility.
     76         updateFragmentVisibility();
     77     }
     78 
     79     @Override
     80     protected void onRestoreInstanceState(Bundle savedInstanceState) {
     81         super.onRestoreInstanceState(savedInstanceState);
     82         // Make sure fragments are updated after check box view state is restored.
     83         updateFragmentVisibility();
     84     }
     85 
     86     // Update fragment visibility based on current check box state.
     87     void updateFragmentVisibility() {
     88         FragmentTransaction ft = getFragmentManager().beginTransaction();
     89         if (mCheckBox1.isChecked()) ft.show(mFragment1);
     90         else ft.hide(mFragment1);
     91         if (mCheckBox2.isChecked()) ft.show(mFragment2);
     92         else ft.hide(mFragment2);
     93         ft.commit();
     94     }
     95 
     96     /**
     97      * A fragment that displays a menu.  This fragment happens to not
     98      * have a UI (it does not implement onCreateView), but it could also
     99      * have one if it wanted.
    100      */
    101     public static class MenuFragment extends Fragment {
    102 
    103         @Override
    104         public void onCreate(Bundle savedInstanceState) {
    105             super.onCreate(savedInstanceState);
    106             setHasOptionsMenu(true);
    107         }
    108 
    109         @Override
    110         public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
    111             menu.add("Menu 1a").setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM);
    112             menu.add("Menu 1b").setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM);
    113         }
    114     }
    115 
    116     /**
    117      * Second fragment with a menu.
    118      */
    119     public static class Menu2Fragment extends Fragment {
    120 
    121         @Override
    122         public void onCreate(Bundle savedInstanceState) {
    123             super.onCreate(savedInstanceState);
    124             setHasOptionsMenu(true);
    125         }
    126 
    127         @Override
    128         public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
    129             menu.add("Menu 2").setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM);
    130         }
    131     }
    132 }
    133