我想为重新创建活动编写测试。执行旋转是可选的。
我希望测试用谷歌“祝福”的最新版本的测试框架编写。我是编写测试的新手，所以我想学习基本的、主流的、支持良好的工具。当我掌握基础知识时，任何第三方测试框架都可以。既然我想测试非常基本的、经常发生的场景，基本的工具就足够了，对吧？
最小测试代码：
public class MainActivity extends AppCompatActivity {
static int creationCounter = 0;
Integer instanceId;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
++creationCounter;
instanceId = new Integer(creationCounter);
Log.d("TEST", "creating activity " + this + ", has id " + instanceId);
}
}
和测试类：
@RunWith(AndroidJUnit4.class)
public class ExampleInstrumentedTest {
@Rule
public ActivityTestRule<MainActivity> mActivityTestRule = new ActivityTestRule<>(MainActivity.class);
@Test
public void useAppContext() throws Exception {
MainActivity activity1 = mActivityTestRule.getActivity();
int act1 = activity1.instanceId.intValue();
int counter1 = MainActivity.creationCounter;
assertEquals(1, counter1);
assertEquals(1, act1);
Log.d("TEST", "requesting rotation");
// method 1
activity1.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
// method 2 //https://gist.github.com/nbarraille/03e8910dc1d415ed9740#file-orientationchangeaction-java
// onView(isRoot()).perform(orientationLandscape());
getInstrumentation().waitForIdleSync(); // I thought this should suffice
// How to do this?
//somehowRefreshActivityInstanceInsideTestRule();
MainActivity activity2 = mActivityTestRule.getActivity();
int act2 = activity2.instanceId.intValue();
int counter2 = MainActivity.creationCounter;
Log.d("TEST", "newly acquired activity " + activity2 + " has id " + act2 + "/" + counter2);
assertEquals(2, counter2);
assertEquals(2, act2);
}
}
上面的代码（方法1或2）给出了logcat：
D/ActivityTestRule: Launching activity example.com.rotationtest.MainActivity
D/TEST: creating activity example.com.rotationtest.MainActivity@47404a3, has id 1
D/TEST: requesting rotation
D/TEST: creating activity example.com.rotationtest.MainActivity@169887e, has id 2
D/TEST: newly acquired activity example.com.rotationtest.MainActivity@47404a3 has id 1/2
I/TestRunner: failed: useAppContext(example.com.rotationtest.ExampleInstrumentedTest)
I/TestRunner: ----- begin exception -----
I/TestRunner: java.lang.AssertionError: expected:<2> but was:<1>
我的诊断，如果我错了，请纠正我：
- activity1.setRequestedOrientation 导致在其他线程中创建新活动。我希望它会收到适当的捆绑
- getInstrumentation().waitForIdleSync(); 导致测试等到新活动被创建
- mActivityTestRule.getActivity(); 仍然返回旧的活动实例。
- 我需要一些方法来刷新测试规则中保存的活动实例，释放以前保存的一个。
我找到了旧版本测试框架的答案：Android 仪器测试 - 如何在方向更改后接收新活动？
mActivity.setRequestedOrientation(
ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
mActivity.finish();
setActivity(null);
mActivity = getActivity();
getInstrumentation().waitForIdleSync();
但我不知道如何将其翻译成新版本。
编辑：
以上两种方法都使活动处于破坏状态： assertFalse(mActivityTestRule.getActivity().isDestroyed()); 失败。
我找到了另一种方法（Destroy and restart Activity with Testing Support Library），它重新创建活动实例，但不通过 onSaveInstanceState 保持其状态