Model View Presenter

Michael Cameron@Darxval

Getting Started - Name that Pattern!

Model - View - Controller

Pros and Cons?

• What are some pros and cons of MVC?

Name that Pattern!

Model - View - Presenter

Views• Not to be confused with widget.view

• The view is a tattle tale

• Rule your views with an Iron Fist

• Tell it what to do

• Let the view tell you of everything that happens.

View Interfaces• Don’t Trust any class, always have a contract

• Contract Details:

• View must let the presenter tell it what to do.

• View must let the presenter know of any events it has received

Presenter

• Tells the view and model objects what to do.

• Handles events

TaskIt!

• Add Tasks

• Have a list of Tasks

• Look at a task in detail

TaskIt MVP

TasksContractinterface View {

void setProgressIndicator(boolean active);

void showTasks(List<Task> tasks);

void showAddTask();

void showTaskDetailUi(String taskId);}

interface UserActionsListener {

void loadTasks(boolean forceUpdate);

void addNewTask();

void openTaskDetails(@NonNull Task requestedTask);}

So… How do you test this??

Inversion of Control

• All you have to do is inject a mock instead of a concrete object to test parts of the app.

Inversion of Controlpublic AddTaskPresenter(@NonNull TasksRepository tasksRepository, @NonNull AddTaskContract.View addTaskView, @NonNull ImageFile imageFile) { mTasksRepository = checkNotNull(tasksRepository); mAddTaskView = checkNotNull(addTaskView); addTaskView.setUserActionListener(this); mImageFile = imageFile;}

Mock vs Concrete/** Prod Debug**/

public class Injection {

public static ImageFile provideImageFile() { return new ImageFileImpl(); }

public static TasksRepository provideTasksRepository() { return TaskRepositories.getInMemoryRepoInstance(new TasksServiceApiImpl()); }}

/** Mock Debug**/

public class Injection {

public static ImageFile provideImageFile() { return new FakeImageFileImpl(); }

public static TasksRepository provideTasksRepository() { return TaskRepositories.getInMemoryRepoInstance(new FakeTasksServiceApiImpl()); }}

Unit Testingpublic class TaskDetailPresenterTest {

public static final String INVALID_ID = "INVALID_ID";

public static final String TITLE_TEST = "title";

public static final String DESCRIPTION_TEST = "description";

@Mock private TasksRepository mTasksRepository;

@Mock private TaskDetailContract.View mTaskDetailView;

/** * {@link ArgumentCaptor} is a powerful Mockito API to capture argument values and use them to * perform further actions or assertions on them. */ @Captor private ArgumentCaptor<TasksRepository.GetTaskCallback> mGetTaskCallbackCaptor;

private TaskDetailPresenter mTaskDetailsPresenter;

@Before public void setupNotesPresenter() { // Mockito has a very convenient way to inject mocks by using the @Mock annotation. To // inject the mocks in the test the initMocks method needs to be called. MockitoAnnotations.initMocks(this);

// Get a reference to the class under test mTasksDetailsPresenter = new TaskDetailPresenter(mTaskRepository, mTaskDetailView); }

Espresso Test@RunWith(AndroidJUnit4.class)@LargeTestpublic class TaskDetailScreenTest {

private static String TASK_TITLE = "TaskIt";

private static String TASK_DESCRIPTION = "Rocks";

private static String TASK_IMAGE = "file:///android_asset/atsl-logo.png";

/** * {@link Note} stub that is added to the fake service API layer. */private static Task TASK = new Task(TASK_TITLE, TASK_DESCRIPTION, TASK_IMAGE);

@Rulepublic ActivityTestRule<TaskDetailActivity> mTaskDetailActivityTestRule = new ActivityTestRule<>(TaskDetailActivity.class, true /* Initial touch mode */, false /* Lazily launch activity */);

@Testpublic void noteDetails_DisplayedInUi() throws Exception { // Check that the note title, description and image are displayed onView(withId(R.id.task_detail_title)).check(matches(withText(TASK_TITLE))); onView(withId(R.id.task_detail_description)).check(matches(withText(TASK_DESCRIPTION))); onView(withId(R.id.task_detail_image)).check(matches(allOf( hasDrawable(), isDisplayed()))); }}

Sources:MVP

https://github.com/konmik/nucleus

Google http://code-labs.io/codelabs/android-testing

J. Amourette -

https://plus.google.com/u/0/photos/102898026333733818285/albums/6081914916274644193/6081914917317951522?pid=6081914917317951522&oid=102898026333733818285

Thank You!