FragmentMenuFragmentSupport.java revision b31c3281d870e9abb673db239234d580dcc4feff
1/* 2 * Copyright (C) 2012 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 com.example.android.supportv4.R; 20 21import androidx.fragment.app.Fragment; 22import androidx.fragment.app.FragmentManager; 23import androidx.fragment.app.FragmentTransaction; 24 25import android.os.Bundle; 26import android.view.LayoutInflater; 27import android.view.View; 28import android.view.ViewGroup; 29import android.view.View.OnClickListener; 30import android.widget.CheckBox; 31 32/** 33 * Demonstrates how fragments can participate in the options menu. 34 */ 35public class FragmentMenuFragmentSupport extends Fragment { 36 Fragment mFragment1; 37 Fragment mFragment2; 38 CheckBox mCheckBox1; 39 CheckBox mCheckBox2; 40 41 // Update fragment visibility when check boxes are changed. 42 final OnClickListener mClickListener = new OnClickListener() { 43 @Override 44 public void onClick(View v) { 45 updateFragmentVisibility(); 46 } 47 }; 48 49 @Override 50 public View onCreateView(LayoutInflater inflater, ViewGroup container, 51 Bundle savedInstanceState) { 52 View v = inflater.inflate(R.layout.fragment_menu, container, false); 53 54 // Make sure the two menu fragments are created. 55 FragmentManager fm = getChildFragmentManager(); 56 FragmentTransaction ft = fm.beginTransaction(); 57 mFragment1 = fm.findFragmentByTag("f1"); 58 if (mFragment1 == null) { 59 mFragment1 = new FragmentMenuSupport.MenuFragment(); 60 ft.add(mFragment1, "f1"); 61 } 62 mFragment2 = fm.findFragmentByTag("f2"); 63 if (mFragment2 == null) { 64 mFragment2 = new FragmentMenuSupport.Menu2Fragment(); 65 ft.add(mFragment2, "f2"); 66 } 67 ft.commit(); 68 69 // Watch check box clicks. 70 mCheckBox1 = (CheckBox)v.findViewById(R.id.menu1); 71 mCheckBox1.setOnClickListener(mClickListener); 72 mCheckBox2 = (CheckBox)v.findViewById(R.id.menu2); 73 mCheckBox2.setOnClickListener(mClickListener); 74 75 // Make sure fragments start out with correct visibility. 76 updateFragmentVisibility(); 77 78 return v; 79 } 80 81 @Override 82 public void onViewStateRestored(Bundle savedInstanceState) { 83 super.onViewStateRestored(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 = getChildFragmentManager().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