IdlingResource Espresso with RxJava

Question

I recently converted my application from using async tasks to rxjava. Now, my espresso tests no longer wait for my data calls to complete due to espresso not having an idling r

Answer 1

Here is how I solved the problem:

IdlingResource implementation:

public class IdlingApiServiceWrapper implements MyRestService, IdlingResource {

private final MyRestService           api;
private final AtomicInteger counter;
private final List callbacks;

public IdlingApiServiceWrapper(MyRestService api) {
    this.api = api;
    this.callbacks = new ArrayList<>();
    this.counter = new AtomicInteger(0);
}

public Observable loadData(){
    counter.incrementAndGet();
    return api.loadData().finallyDo(new Action0() {
        @Override
        public void call() {
            new Handler(Looper.getMainLooper()).post(new Runnable() {
                @Override
                public void run() {
                    counter.decrementAndGet();
                    notifyIdle();
                }
            });
        }
    });
}

@Override public String getName() {
    return this.getClass().getName();
}

@Override public boolean isIdleNow() {
    return counter.get() == 0;
}

@Override public void registerIdleTransitionCallback(ResourceCallback resourceCallback) {
    callbacks.add(resourceCallback);
}

private void notifyIdle() {
    if (counter.get() == 0) {
        for (ResourceCallback cb : callbacks) {
            cb.onTransitionToIdle();
        }
    }
   }
   }

and here is my test:

public class MyActivityTest extends ActivityInstrumentationTestCase2 {
@Inject
IdlingApiServiceWrapper idlingApiWrapper;

@Override
public void setUp() throws Exception {
    //object graph creation

    super.setUp();
    getActivity();
    Espresso.registerIdlingResources(idlingApiWrapper);
}

public void testClickOpenFirstSavedOffer() throws Exception {
    onData(is(instanceOf(DataItem.class)))
            .atPosition(0)
            .perform(click());
   }
  }

I used Dagger for dependency injection.