FragmentStackSupport.java revision c644c91b91b83a6b400a57b02671f4ef7b7a810b 
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 com.example.android.supportv4.R;
20
21import android.support.v4.app.Fragment;
22import android.support.v4.app.FragmentActivity;
23import android.support.v4.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.Button;
31import android.widget.TextView;
32
33public class FragmentStackSupport extends FragmentActivity {
34    int mStackLevel = 1;
35
36    @Override
37    protected void onCreate(Bundle savedInstanceState) {
38        super.onCreate(savedInstanceState);
39        setContentView(R.layout.fragment_stack);
40
41        // Watch for button clicks.
42        Button button = (Button)findViewById(R.id.new_fragment);
43        button.setOnClickListener(new OnClickListener() {
44            public void onClick(View v) {
45                addFragmentToStack();
46            }
47        });
48
49        if (savedInstanceState == null) {
50            // Do first time initialization -- add initial fragment.
51            Fragment newFragment = CountingFragment.newInstance(mStackLevel);
52            FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
53            ft.add(R.id.simple_fragment, newFragment).commit();
54        } else {
55            mStackLevel = savedInstanceState.getInt("level");
56        }
57    }
58
59    @Override
60    public void onSaveInstanceState(Bundle outState) {
61        super.onSaveInstanceState(outState);
62        outState.putInt("level", mStackLevel);
63    }
64
65//BEGIN_INCLUDE(add_stack)
66    void addFragmentToStack() {
67        mStackLevel++;
68
69        // Instantiate a new fragment.
70        Fragment newFragment = CountingFragment.newInstance(mStackLevel);
71
72        // Add the fragment to the activity, pushing this transaction
73        // on to the back stack.
74        FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
75        ft.replace(R.id.simple_fragment, newFragment);
76        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
77        ft.addToBackStack(null);
78        ft.commit();
79    }
80//END_INCLUDE(add_stack)
81
82//BEGIN_INCLUDE(fragment)
83    public static class CountingFragment extends Fragment {
84        int mNum;
85
86        /**
87         * Create a new instance of CountingFragment, providing "num"
88         * as an argument.
89         */
90        static CountingFragment newInstance(int num) {
91            CountingFragment f = new CountingFragment();
92
93            // Supply num input as an argument.
94            Bundle args = new Bundle();
95            args.putInt("num", num);
96            f.setArguments(args);
97
98            return f;
99        }
100
101        /**
102         * When creating, retrieve this instance's number from its arguments.
103         */
104        @Override
105        public void onCreate(Bundle savedInstanceState) {
106            super.onCreate(savedInstanceState);
107            mNum = getArguments() != null ? getArguments().getInt("num") : 1;
108        }
109
110        /**
111         * The Fragment's UI is just a simple text view showing its
112         * instance number.
113         */
114        @Override
115        public View onCreateView(LayoutInflater inflater, ViewGroup container,
116                Bundle savedInstanceState) {
117            View v = inflater.inflate(R.layout.hello_world, container, false);
118            View tv = v.findViewById(R.id.text);
119            ((TextView)tv).setText("Fragment #" + mNum);
120            tv.setBackgroundDrawable(getResources().getDrawable(android.R.drawable.gallery_thumb));
121            return v;
122        }
123    }
124//END_INCLUDE(fragment)
125}
126