1/* 2 * Copyright (C) 2011 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 17package com.example.android.supportv4.app; 18 19import android.os.Bundle; 20import android.view.Menu; 21import android.view.MenuInflater; 22import android.view.MenuItem; 23import android.view.View; 24import android.view.View.OnClickListener; 25import android.widget.CheckBox; 26 27import androidx.fragment.app.Fragment; 28import androidx.fragment.app.FragmentActivity; 29import androidx.fragment.app.FragmentManager; 30import androidx.fragment.app.FragmentTransaction; 31 32import com.example.android.supportv4.R; 33 34/** 35 * Demonstrates how fragments can participate in the options menu. 36 */ 37public class FragmentMenuSupport extends FragmentActivity { 38 Fragment mFragment1; 39 Fragment mFragment2; 40 CheckBox mCheckBox1; 41 CheckBox mCheckBox2; 42 43 // Update fragment visibility when check boxes are changed. 44 final OnClickListener mClickListener = new OnClickListener() { 45 @Override 46 public void onClick(View v) { 47 updateFragmentVisibility(); 48 } 49 }; 50 51 @Override 52 protected void onCreate(Bundle savedInstanceState) { 53 super.onCreate(savedInstanceState); 54 setContentView(R.layout.fragment_menu); 55 56 // Make sure the two menu fragments are created. 57 FragmentManager fm = getSupportFragmentManager(); 58 FragmentTransaction ft = fm.beginTransaction(); 59 mFragment1 = fm.findFragmentByTag("f1"); 60 if (mFragment1 == null) { 61 mFragment1 = new MenuFragment(); 62 ft.add(mFragment1, "f1"); 63 } 64 mFragment2 = fm.findFragmentByTag("f2"); 65 if (mFragment2 == null) { 66 mFragment2 = new Menu2Fragment(); 67 ft.add(mFragment2, "f2"); 68 } 69 ft.commit(); 70 71 // Watch check box clicks. 72 mCheckBox1 = (CheckBox)findViewById(R.id.menu1); 73 mCheckBox1.setOnClickListener(mClickListener); 74 mCheckBox2 = (CheckBox)findViewById(R.id.menu2); 75 mCheckBox2.setOnClickListener(mClickListener); 76 77 // Make sure fragments start out with correct visibility. 78 updateFragmentVisibility(); 79 } 80 81 @Override 82 protected void onRestoreInstanceState(Bundle savedInstanceState) { 83 super.onRestoreInstanceState(savedInstanceState); 84 // Make sure fragments are updated after check box view state is restored. 85 updateFragmentVisibility(); 86 } 87 88 // Update fragment visibility based on current check box state. 89 void updateFragmentVisibility() { 90 FragmentTransaction ft = getSupportFragmentManager().beginTransaction(); 91 if (mCheckBox1.isChecked()) ft.show(mFragment1); 92 else ft.hide(mFragment1); 93 if (mCheckBox2.isChecked()) ft.show(mFragment2); 94 else ft.hide(mFragment2); 95 ft.commit(); 96 } 97 98 /** 99 * A fragment that displays a menu. This fragment happens to not 100 * have a UI (it does not implement onCreateView), but it could also 101 * have one if it wanted. 102 */ 103 public static class MenuFragment extends Fragment { 104 105 @Override 106 public void onCreate(Bundle savedInstanceState) { 107 super.onCreate(savedInstanceState); 108 setHasOptionsMenu(true); 109 } 110 111 @Override 112 public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { 113 MenuItem item; 114 item = menu.add("Menu 1a"); 115 item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM); 116 item = menu.add("Menu 1b"); 117 item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM); 118 } 119 } 120 121 /** 122 * Second fragment with a menu. 123 */ 124 public static class Menu2Fragment extends Fragment { 125 126 @Override 127 public void onCreate(Bundle savedInstanceState) { 128 super.onCreate(savedInstanceState); 129 setHasOptionsMenu(true); 130 } 131 132 @Override 133 public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { 134 MenuItem item; 135 item = menu.add("Menu 2"); 136 item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM); 137 } 138 } 139} 140