android - 如何使用 Robolectric 测试 IntentService？

Question

我正在尝试使用 Robolectric 测试 IntentService 的 onHandleIntent() 方法。

我开始使用以下服务:

Activity activity = new Activity();
Intent intent = new Intent(activity, MyService.class);
activity.startService(intent);

ShadowActivity shadowActivity = Robolectric.shadowOf(activity);
Intent startedIntent = shadowActivity.getNextStartedService();
assertNotNull(startedIntent);

似乎 startedIntent 不为空，但 onHandleIntent() 似乎没有被调用。

我应该如何测试它？

Answer 1

Robolectric 有一个 ServiceController它可以像 Activity 一样贯穿服务生命周期。该 Controller 提供了执行相应服务回调的所有方法(例如 controller.attach().create().startCommand(0, 0).destroy())。

理论上我们可以预期 IntentService.onStartCommand()将通过其内部 Handler 触发 IntentService.onHandleIntent(Intent)。然而，这个 Handler 使用了一个在后台线程上运行的 Looper，我不知道如何让这个线程进入下一个任务。一种解决方法是创建模拟相同行为的 TestService，但会在主线程(用于运行测试的线程)上触发 onHandleIntent(Intent)。

@RunWith(RobolectricGradleTestRunner.class)
public class MyIntentServiceTest {
    private TestService service;
    private ServiceController<TestService> controller;

    @Before
    public void setUp() {
        controller = Robolectric.buildService(TestService.class);
        service = controller.attach().create().get();
    }

    @Test
    public void testWithIntent() {
        Intent intent = new Intent(RuntimeEnvironment.application, TestService.class);
        // add extras to intent
        controller.withIntent(intent).startCommand(0, 0);
        // assert here
    }

    @After
    public void tearDown() {
        controller.destroy();
    }

    public static class TestService extends MyIntentService {
        public boolean enabled = true;

        @Override
        public void onStart(Intent intent, int startId) {
            // same logic as in internal ServiceHandler.handleMessage()
            // but runs on same thread as Service
            onHandleIntent(intent);
            stopSelf(startId);
        }
    }
}

---

更新:或者，为 IntentService 创建一个类似的 Controller 非常简单，如下所示:

public class IntentServiceController<T extends IntentService> extends ServiceController<T> {
    public static <T extends IntentService> IntentServiceController<T> buildIntentService(Class<T> serviceClass) {
        try {
            return new IntentServiceController<>(Robolectric.getShadowsAdapter(), serviceClass);
        } catch (IllegalAccessException | InstantiationException e) {
            throw new RuntimeException(e);
        }
    }

    private IntentServiceController(ShadowsAdapter shadowsAdapter, Class<T> serviceClass) throws IllegalAccessException, InstantiationException {
        super(shadowsAdapter, serviceClass);
    }

    @Override
    public IntentServiceController<T> withIntent(Intent intent) {
        super.withIntent(intent);
        return this;
    }

    @Override
    public IntentServiceController<T> attach() {
        super.attach();
        return this;
    }

    @Override
    public IntentServiceController<T> bind() {
        super.bind();
        return this;
    }

    @Override
    public IntentServiceController<T> create() {
        super.create();
        return this;
    }

    @Override
    public IntentServiceController<T> destroy() {
        super.destroy();
        return this;
    }

    @Override
    public IntentServiceController<T> rebind() {
        super.rebind();
        return this;
    }

    @Override
    public IntentServiceController<T> startCommand(int flags, int startId) {
        super.startCommand(flags, startId);
        return this;
    }

    @Override
    public IntentServiceController<T> unbind() {
        super.unbind();
        return this;
    }

    public IntentServiceController<T> handleIntent() {
        invokeWhilePaused("onHandleIntent", getIntent());
        return this;
    }
}