android - 使用 Robolectric 测试该按钮启动 Activity

Question

您好，我有以下代码:

@RunWith(Test9Runner.class)
public class MainActivityTest 
{
    private MainActivity activity;
    private Button pressMeButton;

    @Before
    public void setUp() throws Exception 
    {
        activity = new MainActivity();
        activity.onCreate(null);
        pressMeButton = (Button) activity.findViewById(R.id.button1);
    }

    @Test
    public void shouldUpdateResultsWhenButtonIsClicked() throws Exception 
    {
        pressMeButton.performClick();
        ShadowActivity shadowActivity = shadowOf(activity);
        Intent intent = shadowActivity.getResultIntent();
        System.out.print(intent.toString());
    }
}

但我不知道如何测试按下 pressMeButton 会启动一个新 Activity。实际上确实如此，但是如何为这个事实编写正确的 Robolectric 单元测试呢？

Answer 1

在 Robolectric 2.1.1 中，您可以验证 Intent 启动新 Activity 是否以下列方式发出。

@RunWith(RobolectricTestRunner.class)
public class MyTest {
  private ShadowActivity shadowActivity;
  private MyActivity activity;

  @Before
  public void setup() {
    activity = new MyActivity();
    shadowActivity = Robolectric.shadowOf(activity);        
  }

  @Test
  public shouldStartNewActivityWhenSomething() {
    //Perform activity startup
    //Do some action which starts second activity, for example View::performClick()
    //...
    //Check Intent
    Intent intent = shadowActivity.peekNextStartedActivityForResult().intent;
    assertThat(intent.getStringExtra(MySecondActivity.EXTRA_MESSAGE)).isEqualTo("blebleble");
    assertThat(intent.getComponent()).isEqualTo(new ComponentName(activity, MySecondActivity.class));
  }
}

这与我正在做的类似。请注意，通过调用 new Activity() 创建 Activity 会使 Robolectric 打印有关不正确创建 Activity 的警告，这可能会做得更好...