How to inject on the ui-thread and wait for the injection to finish before continue?

Question

In Dagger you have to inject on the UI-thread. When running JUnit you are not running on the UI-thread. In order to make it work we have to post a Runnable on the UI-thread and wait for it to finish inject.

My code looks like this:

    public void inject(final Object object) {
        // We always has to inject on the main thread.
        final CountDownLatch latch = new CountDownLatch(1);
        Handler mainHandler = new Handler(FodoApplication.getAppContext().getMainLooper());
        Runnable myRunnable = new Runnable() {
            public void run() {
                objectGraph.inject(object);
            latch.countDown();
            }
        };
        mainHandler.post(myRunnable);
        try {
            latch.await();
        } catch (InterruptedException e) {
            Log.e(TAG, "", e);
        }
    }

The problem is that myRunnable do not start when whe call latch.await(). What is the best way to make Dagger to inject when running the JUnit?

Answer 1

you could use this method from AndroidTestCase : http://developer.android.com/reference/android/app/Instrumentation.html#runOnMainSync(java.lang.Runnable)

This one is also useful : http://developer.android.com/reference/android/test/InstrumentationTestCase.html#runTestOnUiThread(java.lang.Runnable)