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 static androidx.lifecycle.Lifecycle.Event.ON_DESTROY;
20import static androidx.lifecycle.Lifecycle.Event.ON_RESUME;
21
22import static org.hamcrest.CoreMatchers.is;
23import static org.hamcrest.CoreMatchers.not;
24import static org.hamcrest.CoreMatchers.notNullValue;
25import static org.hamcrest.MatcherAssert.assertThat;
26
27import android.app.Instrumentation;
28import android.support.test.InstrumentationRegistry;
29import android.support.test.annotation.UiThreadTest;
30import android.support.test.filters.MediumTest;
31import android.support.test.rule.ActivityTestRule;
32import android.support.test.runner.AndroidJUnit4;
33
34import androidx.fragment.app.test.TestViewModel;
35import androidx.fragment.app.test.ViewModelActivity;
36import androidx.fragment.app.test.ViewModelActivity.ViewModelFragment;
37import androidx.lifecycle.LifecycleObserver;
38import androidx.lifecycle.OnLifecycleEvent;
39import androidx.lifecycle.ViewModelProvider;
40
41import org.junit.Rule;
42import org.junit.Test;
43import org.junit.runner.RunWith;
44
45import java.util.concurrent.CountDownLatch;
46import java.util.concurrent.TimeUnit;
47
48@MediumTest
49@RunWith(AndroidJUnit4.class)
50public class ViewModelTest {
51    private static final int TIMEOUT = 2; // secs
52
53    @Rule
54    public ActivityTestRule<ViewModelActivity> mActivityRule =
55            new ActivityTestRule<>(ViewModelActivity.class);
56
57    @Test(expected = IllegalStateException.class)
58    @UiThreadTest
59    public void testNotAttachedActivity() {
60        // This is similar to calling getViewModelStore in Activity's constructor
61        new FragmentActivity().getViewModelStore();
62    }
63
64    @Test(expected = IllegalStateException.class)
65    @UiThreadTest
66    public void testNotAttachedFragment() {
67        // This is similar to calling getViewModelStore in Fragment's constructor
68        new Fragment().getViewModelStore();
69    }
70
71    @Test
72    public void testSameActivityViewModels() throws Throwable {
73        final TestViewModel[] activityModel = new TestViewModel[1];
74        final TestViewModel[] defaultActivityModel = new TestViewModel[1];
75        final ViewModelActivity[] viewModelActivity = new ViewModelActivity[1];
76        viewModelActivity[0] = mActivityRule.getActivity();
77        mActivityRule.runOnUiThread(new Runnable() {
78            @Override
79            public void run() {
80                activityModel[0] = viewModelActivity[0].activityModel;
81                defaultActivityModel[0] = viewModelActivity[0].defaultActivityModel;
82                assertThat(defaultActivityModel[0], not(is(activityModel[0])));
83
84                ViewModelFragment fragment1 = getFragment(viewModelActivity[0],
85                        ViewModelActivity.FRAGMENT_TAG_1);
86                ViewModelFragment fragment2 = getFragment(viewModelActivity[0],
87                        ViewModelActivity.FRAGMENT_TAG_2);
88                assertThat(fragment1, notNullValue());
89                assertThat(fragment2, notNullValue());
90
91                assertThat(fragment1.activityModel, is(activityModel[0]));
92                assertThat(fragment2.activityModel, is(activityModel[0]));
93
94                assertThat(fragment1.defaultActivityModel, is(defaultActivityModel[0]));
95                assertThat(fragment2.defaultActivityModel, is(defaultActivityModel[0]));
96            }
97        });
98        viewModelActivity[0] = recreateActivity();
99        mActivityRule.runOnUiThread(new Runnable() {
100            @Override
101            public void run() {
102                assertThat(viewModelActivity[0].activityModel, is(activityModel[0]));
103                assertThat(viewModelActivity[0].defaultActivityModel,
104                        is(defaultActivityModel[0]));
105
106                ViewModelFragment fragment1 = getFragment(viewModelActivity[0],
107                        ViewModelActivity.FRAGMENT_TAG_1);
108                ViewModelFragment fragment2 = getFragment(viewModelActivity[0],
109                        ViewModelActivity.FRAGMENT_TAG_2);
110                assertThat(fragment1, notNullValue());
111                assertThat(fragment2, notNullValue());
112
113                assertThat(fragment1.activityModel, is(activityModel[0]));
114                assertThat(fragment2.activityModel, is(activityModel[0]));
115
116                assertThat(fragment1.defaultActivityModel, is(defaultActivityModel[0]));
117                assertThat(fragment2.defaultActivityModel, is(defaultActivityModel[0]));
118            }
119        });
120    }
121
122    @Test
123    public void testSameFragmentViewModels() throws Throwable {
124        final TestViewModel[] fragment1Model = new TestViewModel[1];
125        final TestViewModel[] fragment2Model = new TestViewModel[1];
126        final ViewModelActivity[] viewModelActivity = new ViewModelActivity[1];
127        viewModelActivity[0] = mActivityRule.getActivity();
128        mActivityRule.runOnUiThread(new Runnable() {
129            @Override
130            public void run() {
131                ViewModelFragment fragment1 = getFragment(viewModelActivity[0],
132                        ViewModelActivity.FRAGMENT_TAG_1);
133                ViewModelFragment fragment2 = getFragment(viewModelActivity[0],
134                        ViewModelActivity.FRAGMENT_TAG_2);
135                assertThat(fragment1, notNullValue());
136                assertThat(fragment2, notNullValue());
137
138                assertThat(fragment1.fragmentModel, not(is(fragment2.fragmentModel)));
139                fragment1Model[0] = fragment1.fragmentModel;
140                fragment2Model[0] = fragment2.fragmentModel;
141            }
142        });
143        viewModelActivity[0] = recreateActivity();
144        mActivityRule.runOnUiThread(new Runnable() {
145            @Override
146            public void run() {
147                ViewModelFragment fragment1 = getFragment(viewModelActivity[0],
148                        ViewModelActivity.FRAGMENT_TAG_1);
149                ViewModelFragment fragment2 = getFragment(viewModelActivity[0],
150                        ViewModelActivity.FRAGMENT_TAG_2);
151                assertThat(fragment1, notNullValue());
152                assertThat(fragment2, notNullValue());
153
154                assertThat(fragment1.fragmentModel, is(fragment1Model[0]));
155                assertThat(fragment2.fragmentModel, is(fragment2Model[0]));
156            }
157        });
158    }
159
160    @Test
161    public void testActivityOnCleared() throws Throwable {
162        final ViewModelActivity activity = mActivityRule.getActivity();
163        final CountDownLatch latch = new CountDownLatch(1);
164        final LifecycleObserver observer = new LifecycleObserver() {
165            @SuppressWarnings("unused")
166            @OnLifecycleEvent(ON_DESTROY)
167            void onDestroy() {
168                activity.getWindow().getDecorView().post(new Runnable() {
169                    @Override
170                    public void run() {
171                        try {
172                            assertThat(activity.activityModel.mCleared, is(true));
173                            assertThat(activity.defaultActivityModel.mCleared, is(true));
174                        } finally {
175                            latch.countDown();
176                        }
177                    }
178                });
179            }
180        };
181
182        mActivityRule.runOnUiThread(new Runnable() {
183            @Override
184            public void run() {
185                activity.getLifecycle().addObserver(observer);
186            }
187        });
188        activity.finish();
189        assertThat(latch.await(TIMEOUT, TimeUnit.SECONDS), is(true));
190    }
191
192    @Test
193    public void testFragmentOnClearedWhenFinished() throws Throwable {
194        final ViewModelActivity activity = mActivityRule.getActivity();
195        final ViewModelFragment fragment = getFragment(activity,
196                ViewModelActivity.FRAGMENT_TAG_1);
197        final CountDownLatch latch = new CountDownLatch(1);
198        final LifecycleObserver observer = new LifecycleObserver() {
199            @SuppressWarnings("unused")
200            @OnLifecycleEvent(ON_DESTROY)
201            void onDestroy() {
202                activity.getWindow().getDecorView().post(new Runnable() {
203                    @Override
204                    public void run() {
205                        try {
206                            assertThat(fragment.fragmentModel.mCleared, is(true));
207                        } finally {
208                            latch.countDown();
209                        }
210                    }
211                });
212            }
213        };
214
215        mActivityRule.runOnUiThread(new Runnable() {
216            @Override
217            public void run() {
218                activity.getLifecycle().addObserver(observer);
219            }
220        });
221        activity.finish();
222        assertThat(latch.await(TIMEOUT, TimeUnit.SECONDS), is(true));
223    }
224
225    @Test
226    public void testFragmentOnCleared() throws Throwable {
227        final ViewModelActivity activity = mActivityRule.getActivity();
228        final CountDownLatch latch = new CountDownLatch(1);
229        final LifecycleObserver observer = new LifecycleObserver() {
230            @SuppressWarnings("unused")
231            @OnLifecycleEvent(ON_RESUME)
232            void onResume() {
233                try {
234                    final FragmentManager manager = activity.getSupportFragmentManager();
235                    Fragment fragment = new Fragment();
236                    manager.beginTransaction().add(fragment, "temp").commitNow();
237                    ViewModelProvider viewModelProvider = new ViewModelProvider(fragment,
238                            new ViewModelProvider.NewInstanceFactory());
239                    TestViewModel vm = viewModelProvider.get(TestViewModel.class);
240                    assertThat(vm.mCleared, is(false));
241                    manager.beginTransaction().remove(fragment).commitNow();
242                    assertThat(vm.mCleared, is(true));
243                } finally {
244                    latch.countDown();
245                }
246            }
247        };
248
249        mActivityRule.runOnUiThread(new Runnable() {
250            @Override
251            public void run() {
252                activity.getLifecycle().addObserver(observer);
253            }
254        });
255        assertThat(latch.await(TIMEOUT, TimeUnit.SECONDS), is(true));
256    }
257
258    private ViewModelFragment getFragment(FragmentActivity activity, String tag) {
259        return (ViewModelFragment) activity.getSupportFragmentManager()
260                .findFragmentByTag(tag);
261    }
262
263    private ViewModelActivity recreateActivity() throws Throwable {
264        Instrumentation.ActivityMonitor monitor = new Instrumentation.ActivityMonitor(
265                ViewModelActivity.class.getCanonicalName(), null, false);
266        Instrumentation instrumentation = InstrumentationRegistry.getInstrumentation();
267        instrumentation.addMonitor(monitor);
268        final ViewModelActivity previous = mActivityRule.getActivity();
269        mActivityRule.runOnUiThread(new Runnable() {
270            @Override
271            public void run() {
272                previous.recreate();
273            }
274        });
275        ViewModelActivity result;
276
277        // this guarantee that we will reinstall monitor between notifications about onDestroy
278        // and onCreate
279        //noinspection SynchronizationOnLocalVariableOrMethodParameter
280        synchronized (monitor) {
281            do {
282                // the documentation says "Block until an Activity is created
283                // that matches this monitor." This statement is true, but there are some other
284                // true statements like: "Block until an Activity is destroyed" or
285                // "Block until an Activity is resumed"...
286
287                // this call will release synchronization monitor's monitor
288                result = (ViewModelActivity) monitor.waitForActivityWithTimeout(4000);
289                if (result == null) {
290                    throw new RuntimeException("Timeout. Failed to recreate an activity");
291                }
292            } while (result == previous);
293        }
294        return result;
295    }
296}
297