android-livedata

问题 Background: I have a simple application that fetches movie list using rests API call. The project structure is given below, Activity -> ViewModel -> Repository -> ApiService (Retrofit Interface) The activity subscribes to a LiveData and listens for events changes The ViewModel hosts the MediatorLiveData observed by the activity. Initially the ViewModel sets a Resource.loading(..) value in MediatorLiveData . The ViewModel then calls the repository to get the movie list from ApiService The

问题 I used MVVM architecture to build an Android application with a Repository as a mediation between the ViewModel and Room database. In one of the functions, I retrieve a list of objects from a table in the repository class so that I can call it from the ViewModel class. how to retrieve the first element in the list from the repository class instead of observing the LiveData in any one of the activities? here is my repository class: public class StudentRepository { private StudentDAO

问题 I used MVVM architecture to build an Android application with a Repository as a mediation between the ViewModel and Room database. In one of the functions, I retrieve a list of objects from a table in the repository class so that I can call it from the ViewModel class. how to retrieve the first element in the list from the repository class instead of observing the LiveData in any one of the activities? here is my repository class: public class StudentRepository { private StudentDAO

问题 Short question : What is the correct way to handle database + network on the Paging library from Architecture components, using an API that uses page + size to load a new page and the BoundaryCallback class? Research and explanation Currently the class BoundaryCallback used in the paging library for architecture components, receives as parameter the instance of an element in the list without actual context of where this element is at. It happens in onItemAtFrontLoaded and onItemAtEndLoaded .

问题 Short question : What is the correct way to handle database + network on the Paging library from Architecture components, using an API that uses page + size to load a new page and the BoundaryCallback class? Research and explanation Currently the class BoundaryCallback used in the paging library for architecture components, receives as parameter the instance of an element in the list without actual context of where this element is at. It happens in onItemAtFrontLoaded and onItemAtEndLoaded .

问题 I have an Activity, and it will turn to the fragment-A and then turn to the fragment-B like the following. Activity -> Fragment-A -> Fragment-B situation 1 These two fragment observe the same LiveData for showing snackBar like the following . viewModel.responseData.observe(this, Observer { it.getContentIfNotHandled()?.let { showSnackBar(it) } The livedata in viewModel: var responseData = MutableLiveData<Event<String>>() responseData.value = Event("$message") Error: When I use the above code.

问题 Im building an app following architecture guidelines.Implemented room db caching + network.Need to get latest page number from separate entity. My model: @Entity(tableName = "top_rated_movie_page") public class Top_Rated_Movies_Page { @PrimaryKey(autoGenerate = true) private int db_id; private Integer page; private Integer total_results; private Integer total_pages; @Ignore private List<Result> results; ... Result class contains data which i display in my paged list which observes changes

问题 I am writing unit tests for my viewModel, but having trouble executing the tests. The runBlocking { ... } block doesn't actually wait for the code inside to finish, which is surprising to me. The test fails because result is null . Why doesn't runBlocking { ... } run the launch block inside the ViewModel in blocking fashion? I know if I convert it to a async method that returns a Deferred object, then I can get the object by calling await() , or I can return a Job and call join() . But , I'd

问题 The bounty expires in 5 days . Answers to this question are eligible for a +50 reputation bounty. kgandroid wants to draw more attention to this question. I am updating a LiveData value from a DialogFragment in the ViewModel , but not able to get the value in Fragment. The ViewModel: class OtpViewModel(private val otpUseCase: OtpUseCase, analyticsModel: IAnalyticsModel) : BaseViewModel(analyticsModel) { override val globalNavModel = GlobalNavModel(titleId = R.string.otp_contact_title,

问题 I have following project in Github : https://github.com/Ali-Rezaei/TVMaze I have started to using Koin as dependency injection framework in a sample app : class TVMazeApplication : Application() { override fun onCreate() { super.onCreate() startKoin { androidContext(this@TVMazeApplication) modules(networkModule) modules(persistenceModule) modules(repositoryModule) modules(viewModelModule) } } } This is my repository class : class ShowRepository( private val dao: ShowDao, private val api: