Develop Reference

Multiple LiveData objects in single ViewModel

The structure of my application is as follows:
MainActivity(Activity) containing Bottom Navigation View with three fragments nested below
HomeFragment(Fragment) containing TabLayout with ViewPager with following two tabs
Journal(Fragment)
Bookmarks(Fragment)
Fragment B(Fragment)
Fragment C(Fragment)
I am using Room to maintain all the records of journals. I'm observing one LiveData object each in Journal and Bookmarks fragment. These LiveData objects are returned by my JournalViewModel class.
JournalDatabase.java
public abstract class JournalDatabase extends RoomDatabase {
private static final int NUMBER_OF_THREADS = 4;
static final ExecutorService dbWriteExecutor = Executors.newFixedThreadPool(NUMBER_OF_THREADS);
private static JournalDatabase INSTANCE;
static synchronized JournalDatabase getInstance(Context context) {
if (INSTANCE == null) {
INSTANCE = Room.databaseBuilder(context.getApplicationContext(), JournalDatabase.class, "main_database")
.fallbackToDestructiveMigration()
.build();
}
return INSTANCE;
}
public abstract JournalDao journalDao();
}
JournalRepository.java
public class JournalRepository {
private JournalDao journalDao;
private LiveData<List<Journal>> allJournals;
private LiveData<List<Journal>> bookmarkedJournals;
public JournalRepository(Application application) {
JournalDatabase journalDatabase = JournalDatabase.getInstance(application);
journalDao = journalDatabase.journalDao();
allJournals = journalDao.getJournalsByDate();
bookmarkedJournals = journalDao.getBookmarkedJournals();
}
public void insert(Journal journal) {
JournalDatabase.dbWriteExecutor.execute(() -> {
journalDao.insert(journal);
});
}
public void update(Journal journal) {
JournalDatabase.dbWriteExecutor.execute(() -> {
journalDao.update(journal);
});
}
public void delete(Journal journal) {
JournalDatabase.dbWriteExecutor.execute(() -> {
journalDao.delete(journal);
});
}
public void deleteAll() {
JournalDatabase.dbWriteExecutor.execute(() -> {
journalDao.deleteAll();
});
}
public LiveData<List<Journal>> getAllJournals() {
return allJournals;
}
public LiveData<List<Journal>> getBookmarkedJournals() {
return bookmarkedJournals;
}
}
JournalViewModel.java
public class JournalViewModel extends AndroidViewModel {
private JournalRepository repository;
private LiveData<List<Journal>> journals;
private LiveData<List<Journal>> bookmarkedJournals;
public JournalViewModel(#NonNull Application application) {
super(application);
repository = new JournalRepository(application);
journals = repository.getAllJournals();
bookmarkedJournals = repository.getBookmarkedJournals();
}
public void insert(Journal journal) {
repository.insert(journal);
}
public void update(Journal journal) {
repository.update(journal);
}
public void delete(Journal journal) {
repository.delete(journal);
}
public void deleteAll() {
repository.deleteAll();
}
public LiveData<List<Journal>> getAllJournals() {
return journals;
}
public LiveData<List<Journal>> getBookmarkedJournals() {
return bookmarkedJournals;
}
}
I'm instantiating this ViewModel inside onActivityCreated() method of both Fragments.
JournalFragment.java
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
JournalFactory factory = new JournalFactory(requireActivity().getApplication());
journalViewModel = new ViewModelProvider(requireActivity(), factory).get(JournalViewModel.class);
journalViewModel.getAllJournals().observe(getViewLifecycleOwner(), new Observer<List<Journal>>() {
#Override
public void onChanged(List<Journal> list) {
journalAdapter.submitList(list);
}
});
}
BookmarksFragment.java
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
JournalFactory factory = new JournalFactory(requireActivity().getApplication());
journalViewModel = new ViewModelProvider(requireActivity(), factory).get(JournalViewModel.class);
journalViewModel.getBookmarkedJournals().observe(getViewLifecycleOwner(), new Observer<List<Journal>>() {
#Override
public void onChanged(List<Journal> list) {
adapter.submitList(list);
}
});
}
However, the problem when I use this approach is as I delete make some changes in any of the Fragment like delete or update some Journal some other Journal's date field changes randomly.
I was able to solve this issue by using single LiveData object and observe it in both fragments. The changes I had to make in BookmarkFragment is as follows:
BookmarksFragment.java
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
JournalFactory factory = new JournalFactory(requireActivity().getApplication());
journalViewModel = new ViewModelProvider(requireActivity(), factory).get(JournalViewModel.class);
journalViewModel.getAllJournals().observe(getViewLifecycleOwner(), new Observer<List<Journal>>() {
#Override
public void onChanged(List<Journal> list) {
List<Journal> bookmarkedJournals = new ArrayList<>();
for (int i = 0; i < list.size(); i++) {
if (list.get(i).getBookmark() == 1)
bookmarkedJournals.add(list.get(i));
}
adapter.submitList(bookmarkedJournals);
}
});
}
It works properly now.
However, I want to know why it didn't work using my first approach which was to use two different LiveData objects and observe them in different fragments.
Are multiple LiveData objects not meant to be used in single ViewModel?
OR
Are two instances of same ViewModel not allowed to exist together while making changes and fetching different LiveData objects from the same table simultaneously?

I found out the reason causing this problem.
As I was using LiveData with getViewLifecycleOwner() as the LifecycleOwner, the observer I passed as parameter was never getting removed. So, after switching to a different tab, there were two active observers observing different LiveData objects of same ViewModel.
The way this issue can be solved is by storing the LiveData object in a variable then removing the observer as you switch to different fragment.
In my scenario, I solved this issue by doing the following:
//store LiveData object in a variable
LiveData<List<Journal>> currentLiveData = journalViewModel.getAllJournals();
//observe this livedata object
currentLiveData.observer(observer);
Then remove this observer in a suitable Lifecycle method or anywhere that suits your needs like
#Override
public void onDestroyView() {
super.onDestroyView();
//if you want to remove all observers
currentLiveData.removeObservers(getViewLifecycleOwner());
//if you want to remove particular observers
currentLiveData.removeObserver(observer);
}

Recyclerview data disappears when device is rotated

Even though I am using ViewModel, whenever the device is rotated, the data in the Recyclerview disappears. I had to put the makeSearch() method inside the onClick() method because I need to get the text that the button grabs and use it as the search parameter. Is there a better way I can handle this to avoid this problem? My code is right here:
SearchActivity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_search);
// What happens when the search button is clicked
materialButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (Objects.requireNonNull(textInputEditText.getText()).toString().isEmpty()) {
textInputEditText.setError("Type a search query");
} else {
mSearchInput = Objects.requireNonNull(textInputEditText.getText()).toString();
textInputEditText.setText("");
makeSearch();
}
}
});
}
// Gets the ViewModel, Observes the Question LiveData and delivers it to the Recyclerview
private void makeSearch() {
final SearchAdapter searchAdapter = new SearchAdapter();
SearchViewModel mSearchViewModel = new ViewModelProvider(this,
new CustomSearchViewModelFactory(new SearchRepository())).get(SearchViewModel.class);
mSearchViewModel.setQuery(mSearchInput);
mSearchViewModel.getQuestionLiveData().observe(this, new Observer<List<Question>>() {
#Override
public void onChanged(List<Question> questions) {
mQuestions = questions;
searchAdapter.setQuestions(questions);
}
});
mRecyclerView.setAdapter(searchAdapter);
searchAdapter.setOnClickListener(mOnClickListener);
}
SearchViewModel:
public class SearchViewModel extends ViewModel {
private SearchRepository mSearchRepository;
private MutableLiveData<String> mSearchLiveData = new MutableLiveData<>();
private LiveData<List<Question>> mQuestionLiveData = Transformations.switchMap(mSearchLiveData, (query) -> {
return mSearchRepository.getQuestions(query);
});
SearchViewModel(SearchRepository searchRepository) {
this.mSearchRepository = searchRepository;
}
public LiveData<List<Question>> getQuestionLiveData() {
return mQuestionLiveData;
}
public void setQuery(String query) {
mSearchLiveData.setValue(query);
}
}
SearchRepository:
public class SearchRepository {
//private String inTitle;
private MutableLiveData<List<Question>> mQuestions = new MutableLiveData<>();
public SearchRepository() {
//getQuestionsWithTextInTitle();
}
private void getQuestionsWithTextInTitle(String inTitle) {
ApiService apiService = RestApiClient.getApiService(ApiService.class);
Call<QuestionsResponse> call = apiService.getQuestionsWithTextInTitle(inTitle);
call.enqueue(new Callback<QuestionsResponse>() {
#Override
public void onResponse(Call<QuestionsResponse> call, Response<QuestionsResponse> response) {
QuestionsResponse questionsResponse = response.body();
if (questionsResponse != null) {
mQuestions.postValue(questionsResponse.getItems());
//shouldShowData = true;
} else {
Log.d("SearchRepository", "No matching question");
//shouldShowData = false;
}
}
#Override
public void onFailure(Call<QuestionsResponse> call, Throwable t) {
//shouldShowData = false;
t.printStackTrace();
}
});
}
public LiveData<List<Question>> getQuestions(String inTitle) {
getQuestionsWithTextInTitle(inTitle);
return mQuestions;
}
}

Your approach of passing the search input in through your CustomSearchViewModelFactory and into the constructor for the ViewModel and into the constructor for your SearchRepository isn't going to work in any case. While the first time you search your CustomSearchViewModelFactory creates the ViewModel, the second time you hit search, your SearchViewModel is already created and your factory is not invoked a second time, meaning you never get the second query.
Instead, you should file the ViewModel Overview documentation, and use Transformations.switchMap() to convert your input (the search string) into a new LiveData<List<Question>> for that given query.
This means that your ViewModel would look something like
public class SearchViewModel extends ViewModel {
private SearchRepository mSearchRepository;
private MutableLiveData<String> mSearchLiveData = new MutableLiveData<String>();
private LiveData<List<Question>> mQuestionLiveData =
Transformations.switchMap(mSearchLiveData, (query) -> {
return mSearchRepository.getQuestions(query);
});
public SearchViewModel() {
mSearchRepository = new SearchRepository();
}
public void setQuery(String query) {
mSearchLiveData.setValue(query);
}
public LiveData<List<Question>> getQuestionLiveData() {
return mQuestionLiveData;
}
}
You'd then update your Activity to:
Always observe the getQuestionLiveData() (note that you won't get a callback to your Observer until you actually set the first query)
Call setQuery() on your SearchViewModel in your makeSearch()
Remove your CustomSearchViewModelFactory entirely (it would no longer be needed).

How to get Call Back from ViewModel to View in Android

I have ViewModel
class MyViewModel extends BaseViewModel{
public void foo(){
// some code or return some boolean
}
}
View Class
class MyView extends View{
private MyViewModel myviewmodel;
public void bindTo(MyViewModel viewModel) {
this.viewModel = viewModel;
context = viewModel.getContext();
validateView();
requestLayout();
}
private validateView(){
//some code
}
}
this bind view method bind with adapter
I want to get call back in Myview class when ever i will validateView will call please suggest me how get call back from Viewmodel method to View in android.

it is best practice to use live data for communicating from viewmodel to your view.
class MyViewModel {
private MutableLiveData<Boolean> state = new MutableLiveData<Boolean>;
public LiveData<Boolean> getState() {
return state;
}
public void foo() {
//bool = value returned of your work
state.setValue(bool);
} }
class Myview extends View {
public void onCreate() {
viewmodel.getState().observe(this, observer); // 'this' is life cycle owner
}
final Observer<Boolean> observer = new Observer<Boolean>() {
#Override
public void onChanged(#Nullable final Boolean state) {
// do your work with returned value
}
}; }
for more details refer to this

Correct Me if i wrong
first you need to make interface class
public interface ViewModelCallback {
void returnCallBack(Boolean mBoolean);
}
then your View class implements that interface class & Override that method
class MyView extends View implements ViewModelCallback
#Override
public void returnCallBack(Boolean mBoolean) {
//here you will retrieve callback
// Do Something
}
Next you just pass a value from your view model
class MyViewModel {
private ViewModelCallback myViewCallBack;
public void foo() {
Boolean yourReturnValue = false;
myViewCallBack.returnCallBack(yourReturnValue);
}
}

Espresso's IdlingResource with Retrofit 2

I am new to Espresso, and trying to write a test on a fragment that makes a Retrofit call when it is instantiated. When the call is received, I want to check the fragment to see if a view exists. I'm using an IdlingResource for the fragment and setting up a listener to be called that transitions the ResourceCallback to idle when the response is received (followed some steps in the implementation here: https://stackoverflow.com/a/30820189/4102823).
My fragment is instantiated when the user logs in and starts up MainActivity. The problem is that I just don't think my IdlingResource is set up correctly, and I don't know what's wrong with it. It is not even constructed until after the fragment is initiated and the call is made, even though I'm registering the IdlingResource in the test's setUp() method before everything else. So, I think the main issue here is how I get the IdlingResource instantiated alongside the fragment when I run the test, not after it. Could the problem be in the #Rule? Does it start MainActivity (which creates a NewsfeedFragment instance) before the test can run on the fragment? If so, how would I use a rule with my fragment instead?
Here is my fragment:
public ProgressListener mProgressListener;
public boolean mIsProgressShown = true;
public interface ProgressListener {
void onProgressShown();
void onProgressDismissed();
}
public void setProgressListener(ProgressListener progressListener) {
mProgressListener = progressListener;
}
public NewsfeedFragment() {
}
public static NewsfeedFragment newInstance() {
return new NewsfeedFragment();
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
OSUtil.setTranslucentStatusBar(getActivity().getWindow(), this.getContext());
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
mRootView = (SwipeRefreshLayout) inflater.inflate(R.layout.fragment_newsfeed, container, false);
mNewsfeedFramelayout = (FrameLayout) mRootView.findViewById(R.id.newsfeed_framelayout);
mProgressView = (ProgressBar) mRootView.findViewById(R.id.newsfeed_progress);
mPageIndictorView = (FrameLayout) mRootView.findViewById(R.id.page_indicator);
mPageIndicator = (TextView) mRootView.findViewById(R.id.page_indicator_text);
mRootView.setOnRefreshListener(this);
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) mRootView.findViewById(R.id.newsfeed_viewpager);
mPageChangeListener = this;
if (savedInstanceState != null) {
mTabPosition = savedInstanceState.getInt(EXTRA_TAB_POSITION);
mViewPager.setCurrentItem(mTabPosition);
}
fetchNewsFeed();
return mRootView;
}
private void fetchNewsFeed() {
if (NetworkUtils.isConnectedToInternet(getActivity())) {
if (NetworkUtils.getService() != null) {
if (mRootView.isRefreshing()) {
dismissProgress();
} else {
showProgress();
}
showProgress();
Call<Newsfeed> call = NetworkUtils.getService().getNewsfeed();
call.enqueue(new Callback<Newsfeed>() {
#Override
public void onResponse(Call<Newsfeed> call, Response<Newsfeed> response) {
if (response.isSuccessful()) {
dismissProgress();
mNewsfeed = response.body();
FragmentManager fragmentManager = getChildFragmentManager();
mNewsfeedPagerAdapter = new NewsfeedPagerAdapter(fragmentManager, mNewsfeed.getNewsfeedItems());
}
...
private void showProgress() {
// show the progress and notify the listener
if (mProgressListener != null){
setProgressIndicatorVisible(true);
notifyListener(mProgressListener);
}
}
public void dismissProgress() {
// hide the progress and notify the listener
if (mProgressListener != null){
setProgressIndicatorVisible(false);
mIsProgressShown = false;
notifyListener(mProgressListener);
}
}
public boolean isInProgress() {
return mIsProgressShown;
}
private void notifyListener(ProgressListener listener) {
if (listener == null){
return;
}
if (isInProgress()){
listener.onProgressShown();
}
else {
listener.onProgressDismissed();
}
}
Here is the IdlingResource:
public class ProgressIdlingResource implements IdlingResource, NewsfeedFragment.ProgressListener {
private ResourceCallback mResourceCallback;
private NewsfeedFragment mNewsfeedFragment;
public ProgressIdlingResource(NewsfeedFragment fragment) {
mNewsfeedFragment = fragment;
mNewsfeedFragment.setProgressListener(this);
}
#Override
public String getName() {
return "ProgressIdlingResource";
}
#Override
public boolean isIdleNow() {
return !mNewsfeedFragment.mIsProgressShown;
}
#Override
public void registerIdleTransitionCallback(ResourceCallback callback) {
mResourceCallback = callback;
}
#Override
public void onProgressShown() {
}
#Override
public void onProgressDismissed() {
if (mResourceCallback == null) {
return;
}
//Called when the resource goes from busy to idle.
mResourceCallback.onTransitionToIdle();
}
}
The fragment test:
public class NewsfeedFragmentTest {
#Before
public void setUp() throws Exception {
Espresso.registerIdlingResources(new ProgressIdlingResource((NewsfeedFragment) MainActivity.getCurrentFragment()));
}
#Rule
public ActivityTestRule<MainActivity> mActivityTestRule = new ActivityTestRule<>(MainActivity.class);
#Test
public void getViewPager() throws Exception {
onView(allOf(withEffectiveVisibility(ViewMatchers.Visibility.VISIBLE),
withId(R.id.newsfeed_viewpager))).check(matches(isDisplayed()));
}
#Test
public void getNewsfeedItems() throws Exception {
onView(withId(R.id.page_indicator)).check(matches(isDisplayed()));
}
}

Retrofit is using OkHttp, and there is a standard way to setup IdlingResource for that matter. Refer to OkHttp IdlingResource

Android unit testing fragment with roboletric in MPV application

I am reinventing my app using a classic MVP approach. In order to to this I read many many articles and tutorials, and what I came out with is that the best way is to :
create an interface for the presenter and one for the view
make fragments and activities implements view interfaces
create an implementation of the presenter interface, which takes in the constructor an instance of the the view it manages, and hold a reference to the presenter inside the view's implementation.
So I have created this classes
VIEW INTERFACE
public interface SignupEmailView extends BaseView {
void fillEmail(String email);
void onEmailInvalid(String error);
void onDataValidated();
}
PRESENTER INTERFACE
public interface SignupEmailPresenter {
void initData(Bundle bundle);
void validateData(String email);
}
VIEW IMPLEMENTATION
public class FrSignup_email extends BaseSignupFragmentMVP implements IBackHandler, SignupEmailView {
public static String PARAM_EMAIL = "param_email";
#Bind(R.id.signup_step2_new_scrollview)
ScrollView mScrollview;
#Bind(R.id.signup_step2_new_lblTitle)
SuperLabel mLblTitle;
#Bind(R.id.signup_step2_new_lblSubtitle)
TextView mLblSubtitle;
#Bind(R.id.signup_step2_new_txtEmail)
EditText mTxtEmail;
#Bind(R.id.signup_step2_new_btnNext)
Button mBtnNext;
protected SignupActivityView mActivity;
SignupEmailPresenter mPresenter;
public FrSignup_email() {
// Required empty public constructor
}
public static FrSignup_email newInstance(String email) {
FrSignup_email fragment = new FrSignup_email();
Bundle b = new Bundle();
b.putString(PARAM_EMAIL, email);
fragment.setArguments(b);
return fragment;
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mActivity = (SignupActivityView) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString()
+ " must implement IResetPasswordBridge");
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = loadView(inflater, container, savedInstanceState, R.layout.fragment_signup_email);
mPresenter = new SignupEmailPresenterImpl(this);
ButterKnife.bind(this, view);
return view;
}
#Override
public final void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
applyCircularReveal();
mPresenter.initData(this.getArguments());
mTxtEmail.setImeOptions(EditorInfo.IME_ACTION_NEXT);
mTxtEmail.setOnEditorActionListener(new TextView.OnEditorActionListener() {
#Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
if (actionId == EditorInfo.IME_ACTION_NEXT) {
mPresenter.validateData(mTxtEmail.getText().toString());
return true;
}
return false;
}
});
mTxtEmail.setOnTouchListener(new OnTouchCompoundDrawableListener_NEW(mTxtEmail, new OnTouchCompoundDrawableListener_NEW.OnTouchCompoundDrawable() {
#Override
public void onTouch() {
mTxtEmail.setText("");
}
}));
mBtnNext.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mPresenter.validateData(mTxtEmail.getText().toString());
}
});
}
#Override
public void fillEmail(String email) {
mTxtEmail.setText(email);
}
#Override
public void onEmailInvalid(String error) {
displayError(error);
}
#Override
public void onDataValidated() {
changeFieldToValid(mTxtEmail);
setEmail(mTxtEmail.getText().toString());
// the activity shows the next fragment
mActivity.onEmailValidated();
}
#Override
public boolean doBack() {
if (!isLoading()) {
mActivity.onEmailBack();
}
return true;
}
#Override
public void displayError(String error) {
changeFieldToInvalid(mTxtEmail);
mLblSubtitle.setText(error);
mLblSubtitle.setTextColor(ContextCompat.getColor(getActivity(), R.color.field_error));
}
}
PRESENTER IMPLEMENTATION
public class SignupEmailPresenterImpl implements SignupEmailPresenter {
private SignupEmailView mView;
public SignupEmailPresenterImpl(SignupEmailView view) {
mView = view;
}
#Override
public void initData(Bundle bundle) {
if (bundle != null) {
mView.fillEmail(bundle.getString(FrSignup_email.PARAM_EMAIL));
}
}
#Override
public void validateData(String password) {
ValidationUtils_NEW.EmailStatus status = ValidationUtils_NEW.validateEmail(password);
if (status != ValidationUtils_NEW.EmailStatus.VALID) {
mView.onEmailInvalid(ValidationUtils_NEW.getEmailErrorMessage(status));
} else {
mView.onDataValidated();
}
}
}
Now the fragment is held by an activity which implements this view interface and has its own presenter
public interface SignupActivityView extends BaseView {
void onEmailValidated();
void onPhoneNumberValidated();
void onPasswordValidated();
void onUnlockCodeValidated();
void onResendCodeClick();
void onEmailBack();
void onPhoneNumberBack();
void onPasswordBack();
void onConfirmCodeBack();
void onSignupRequestSuccess(boolean resendingCode);
void onSignupRequestFailed(String errorMessage);
void onTokenCreationFailed();
void onUnlockSuccess();
void onUnlockError(String errorMessage);
void showTermsAndConditions();
void hideTermsAndConditions();
}
My idea is to have a unit test for each project unit, so for each view and presenter implementation I want a unit test, so I want to unit test my fragment with roboletric, and for example I want to test that if I click the "NEXT" button and the email is correct, the hosting Activity's onEmailValidated()method is called. This is my test class
public class SignupEmailViewTest {
private SignupActivity_NEW mActivity;
private SignupActivity_NEW mSpyActivity;
private FrSignup_email mFragment;
private FrSignup_email mSpyFragment;
private Context mContext;
#Before
public void setUp() {
final Context context = RuntimeEnvironment.application.getApplicationContext();
this.mContext = context;
mActivity = Robolectric.buildActivity(SignupActivity_NEW.class).create().visible().get();
mSpyActivity = spy(mActivity);
mFragment = FrSignup_email.newInstance("");
mSpyFragment =spy(mFragment);
mSpyActivity.getFragmentManager()
.beginTransaction()
.replace(R.id.signupNew_fragmentHolder, mSpyFragment)
.commit();
mSpyActivity.getFragmentManager().executePendingTransactions();
}
#Test
public void testEmailValidation() {
assertTrue(mSpyActivity.findViewById(R.id.signup_step2_new_lblTitle).isShown());
assertTrue(mSpyActivity.findViewById(R.id.signup_step2_new_lblSubtitle).isShown());
mSpyActivity.findViewById(R.id.signup_step2_new_btnNext).performClick();
assertTrue(((SuperLabel) mSpyActivity.findViewById(R.id.signup_step2_new_lblSubtitle)).getText().equals(mContext.getString(R.string.email_empty)));
((EditText) mSpyActivity.findViewById(R.id.signup_step2_new_txtEmail)).setText("aaa#bbb.ccc");
mSpyActivity.findViewById(R.id.signup_step2_new_btnNext).performClick();
verify(mSpyFragment).onDataValidated();
verify(mSpyActivity).onEmailValidated();
}
}
everything works well, is just the last verify which doesn't work. Note that the previous verify works, so onEmailValidated is called for sure.
Aside from this specific case, I have some point to discuss:
If with roboeletric I am forced to use an activity to instantiate a fragment, how can I test the fragment in complete isolation (which would be the unit tests goal)? I mean, if I use Robolectric.setupActivity(MyActivity.class) and the activity instantiates somewhere a fragment, it will load the activity and the fragment, which is good, but what if the activity manages a flow of fragments? How can I test the second or third fragment without manually navigating to it? Someone can say to use a dummy activity and use FragmentTestUtil.startFragment, but what in the fragment's onAttach() method is implemented the bridging with the parent activity? Is it me going on the wrong way or are this problems still unsolved?
thanks

Actually you don't even require Roboelectric to do any of those tests.
If each fragment/activity implements a different view interface you could implement fake views and instantiate those instead of the activity/fragment. In this way you could have isolated tests.
If you don't want to implement all the methods of the view interface you could use Mockito and stub only the ones that your unit test requires.
Let me know if you need sample code.