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 
17 package com.example.android.apis.app;
18 
19 import com.example.android.apis.R;
20 
21 import android.app.Fragment;
22 import android.app.FragmentTransaction;
23 import android.os.Bundle;
24 import android.view.LayoutInflater;
25 import android.view.View;
26 import android.view.ViewGroup;
27 import android.view.View.OnClickListener;
28 import android.widget.Button;
29 
30 public class FragmentStackFragment extends Fragment {
31     int mStackLevel = 1;
32 
33     @Override
onCreate(Bundle savedInstanceState)34     public void onCreate(Bundle savedInstanceState) {
35         super.onCreate(savedInstanceState);
36 
37         if (savedInstanceState == null) {
38             // Do first time initialization -- add initial fragment.
39             Fragment newFragment = FragmentStack.CountingFragment.newInstance(mStackLevel);
40             FragmentTransaction ft = getChildFragmentManager().beginTransaction();
41             ft.add(R.id.simple_fragment, newFragment).commit();
42         } else {
43             mStackLevel = savedInstanceState.getInt("level");
44         }
45     }
46 
47     @Override
onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)48     public View onCreateView(LayoutInflater inflater, ViewGroup container,
49             Bundle savedInstanceState) {
50         View v = inflater.inflate(R.layout.fragment_stack, container, false);
51 
52         // Watch for button clicks.
53         Button button = (Button)v.findViewById(R.id.new_fragment);
54         button.setOnClickListener(new OnClickListener() {
55             public void onClick(View v) {
56                 addFragmentToStack();
57             }
58         });
59         button = (Button)v.findViewById(R.id.delete_fragment);
60         button.setOnClickListener(new OnClickListener() {
61             public void onClick(View v) {
62                 getChildFragmentManager().popBackStack();
63             }
64         });
65 
66         return v;
67     }
68 
69     @Override
onSaveInstanceState(Bundle outState)70     public void onSaveInstanceState(Bundle outState) {
71         super.onSaveInstanceState(outState);
72         outState.putInt("level", mStackLevel);
73     }
74 
addFragmentToStack()75     void addFragmentToStack() {
76         mStackLevel++;
77 
78         // Instantiate a new fragment.
79         Fragment newFragment = FragmentStack.CountingFragment.newInstance(mStackLevel);
80 
81         // Add the fragment to the activity, pushing this transaction
82         // on to the back stack.
83         FragmentTransaction ft = getChildFragmentManager().beginTransaction();
84         ft.replace(R.id.simple_fragment, newFragment);
85         ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
86         ft.addToBackStack(null);
87         ft.commit();
88     }
89 }
90