1/*
2 * Copyright 2018 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 androidx.fragment.app;
18
19import android.os.Bundle;
20
21public class ReentrantFragment extends StrictFragment {
22    private static final String FROM_STATE = "fromState";
23    private static final String TO_STATE = "toState";
24    int mFromState = 0;
25    int mToState = 0;
26    boolean mIsRestored;
27
28    public static ReentrantFragment create(int fromState, int toState) {
29        ReentrantFragment fragment = new ReentrantFragment();
30        fragment.mFromState = fromState;
31        fragment.mToState = toState;
32        fragment.mIsRestored = false;
33        return fragment;
34    }
35
36    @Override
37    public void onStateChanged(int fromState) {
38        super.onStateChanged(fromState);
39        // We execute the transaction when shutting down or after restoring
40        if (fromState == mFromState && mState == mToState
41                && (mToState < mFromState || mIsRestored)) {
42            executeTransaction();
43        }
44    }
45
46    private void executeTransaction() {
47        getFragmentManager().beginTransaction()
48                .add(new StrictFragment(), "should throw")
49                .commitNow();
50    }
51
52    @Override
53    public void onSaveInstanceState(Bundle outState) {
54        super.onSaveInstanceState(outState);
55        outState.putInt(FROM_STATE, mFromState);
56        outState.putInt(TO_STATE, mToState);
57    }
58
59    @Override
60    public void onCreate(Bundle savedInstanceState) {
61        if (savedInstanceState != null) {
62            mFromState = savedInstanceState.getInt(FROM_STATE);
63            mToState = savedInstanceState.getInt(TO_STATE);
64            mIsRestored = true;
65        }
66        super.onCreate(savedInstanceState);
67    }
68}
69
70