That's how your code looks.viewModel.priceList.observe(lcowner, { Scaffold( content = { CryptoContent(it) }) }) You can't show data that's not yet available.

Don't do that.LiveData has his address. And listeners are signing up on this address. You've got a new LiveData coming back from the D.O.R. with a new address, and listeners don't know it.Try changing your code to the next.val currentGoal: LiveData<Goal> = MutableLiveData() // LiveData лучше делать VAL // когда приходит ответ из БД, вам надо только поменять значение в LD, а не всю ее целиком (проблема с новым "адресом") fun initGoal(id: Long) { currentGoal.value = goalDao.getLiveById(id) } @Query("SELECT * FROM goal WHERE id = :id") fun getLiveById(id: Long): Goal

It's a work code. WeatherResponse was wrong.

Like the way it is.sealed class Response<out R> { data class Success<out T>(val data: T) : Response<T>() data class Error(val exception: Exception) : Response<Nothing>() object Loading : Response<Nothing>() } // ViewModel val data: LiveData<Response<List<Share>>> = loadData() private fun loadData(): LiveData<Response<List<Share>>> = liveData(viewModelScope.coroutineContext + Dispatchers.IO) { emit(Response.Loading) try { emit(repository.fetch) } catch (exception: Exception) { emit(Response.Error(exception)) } } // View (Fragment) viewModel.data.observe(viewLifecycleOwner, { response -> when (response) { is Response.Loading -> { } is Response.Success -> { } is Response.Error -> { } } }) The mistake arises because fetch You. LiveData<List<Share>>♪ Try your example:private fun fetch(): LiveData<List<Share>> { val liveData: LiveData<List<String>> loadingStateLiveData.value = LoadingState.LOADING viewModelScope.launch(Dispatchers.IO) { try { liveData = repository.fetch loadingStateLiveData .postValue(LoadingState.LOADED) } catch (e: Exception) { } } return liveData }

I am. The postValue() method is operated from the background flow, so the value comes there with a delay. You can use the setValue(s) working from the main flow, then all active observers will instantly get a new meaning. For all the details of mercy, please contact the documentation: https://developer.android.com/reference/androidx/lifecycle/LiveData#postValue(T)

You have different ViewModel installations.Use the fragment in another fragment. childFragmentManagerCategoryDialog().show(childFragmentManager, CategoryDialog.TAG) And if you want to get in the subsidiary of ViewModel from the parent fragment, use it. by viewModels({ requireParentFragment() }) or by activityViewModels()

The solution was thatprivate val favouriteFactory by lazy { object : DataSource.Factory<Int, Movie>() { override fun create(): DataSource<Int, Movie> = dao.getMovieListPagingFavoriteSearch("%${query.value!!}%").map { it as Movie }.create() } } val liveDataFavorite: LiveData&lt;PagedList&lt;Movie&gt;&gt; by lazy { favouriteFactory.toLiveData(config = config) } And it's just that you change the invalidate.

In response to the second question, I would advise you to use the library. Moxy (sighs) https://github.com/Arello-Mobile/Moxy ) She's very comfortable working with her. Representative Pattern design MVPand automatically retains your activism/fragment. There's a few videos on the utubus for this library. Personally, when I wrote my project from MVM to MVP, I used this library and this video. https://www.youtube.com/watch?v=OHzTBEBYNAM&t=2645s And it worked well. Good luck!

LiveData Focused on immutable facilities. I mean, if your object has changed, you have to provide a completely new facility, in your case, just once again. setData(...)may have pre-tested whether real changes have been made.Talking about it. RecyclerViewthe same story.Used DiffUtil You'll get a modified object, compare it to the old one, make payload with changes, it'll be in. public void onBindViewHolder(@NonNull VH holder, int position, @NonNull List<Object> payloads) in the adapter, and you'll be able to make the necessary changes, but only those that really changed. And notifyDataSetChanged You don't have to use it, even if you want to.

Replace.this.employeeList = data♪this.employeeList.clear(); this.employeeList.addAll(data); DoataSetChanged doesn't work, because you don't change the data already available but replace them with new ones.

As an option to take the Observer to and from the variable

Try xml.android:text="@{String.valueOf(viewmodel.item.name)}

If the data collection is null, it should be indicated that itemCount = 0. Either rFoodList should be NonNull. @Override public int getItemCount() { return rFoodList != null? rFoodList.size() : 0; } ♪ foodList We need to sign in the method onCreate Activity, but it is necessary to initialize foodList, foodList = new MutableLiveData<>()♪foodList.observe(this, new Observer<List<FoodData>>() { @Override public void onChanged(@Nullable List<FoodData> value) { productsRecycler.setAdapter(new ProductsAdapter(value)); } }); //задаем тестовые данные private void initTestList() { FoodData foodData1 = new FoodData("Name1", 2.0) ; FoodData foodData2 = new FoodData("Name2", 2.0) ; FoodData foodData3 = new FoodData("Name3", 2.0) ; testList = new ArrayList<>(); testList.add(foodData1) ; testList.add(foodData2) ; testList.add(foodData3) ; foodList.postValue(testList); } private void initRepo(final Context context) { Thread thread = new Thread(new Runnable() { @Override public void run() { fridgeRepository = new FridgeRepository(ProductsActivity.this) ; foodList.postValue(fridgeRepository.getFoodDataList());//если метод getFoodDataList возвращает List<FoodData>. //если getFoodDataList возвращает LiveData то нужно подписаваться на него напрямую, а не использовать локальный foodList } }); thread.start(); } Yeah, well, I'd rather start understanding LiveData's work. That's a simple lesson to understand: https://startandroid.ru/ru/courses/architecture-components/27-course/architecture-components/525-urok-2-livedata.html p.s. LayoutManager for RecyclerView needs to be indicated before the set Adapter.productsRecycler.setLayoutManager(linearLayoutManager); productsRecycler.setAdapter(new ProductsAdapter(testList));

Your function will return the object immediately. datathe programme will not await the outcome of the request. This data is LiveData, so you can just sign it and as soon as you get it. onResponse() All subscribers will be notified.

I think you've incorrectly built interaction with your adapter. Adapter shouldn't know anything about LiveData and other kitchens. The entire task of the adapter is to just decorate the list he was fed with. I'd recommend you take a signature on LiveData to View where the adapter is located and signed for it. And the method of adapter updateUi(s) leads to the kind of thing public void updateAdapter(List<Task> tasks){ this.tasks = tasks; notifyDataSetChanged(); } And by updating your OBD, you'll just update the list inside the adapter. What you don't have is probably because either the reference is lost on LiveData himself or on your list. There's got to be more detailed.

I think it should help: private fun madLiveData(): LiveData<Int> { return Transformations.map(dao.getLiveDataModel()) { model: Model -> doSomething(model) model.id } } private fun doSomething(Model: Model) { //do something } You can see more about LiveData. https://startandroid.ru/ru/courses/architecture-components/27-course/architecture-components/526-urok-3-livedata.html

Option one, and I think it's right. I'm gonna break the model. The signature receives data and gives them the adapter RecyclerView. The same adapter has display parameters that sort the data inside the adapter as you need. In selecting the user of another sorting, the parameters of the adapter shall be changed, but the subscription and observe shall not change.Option two, generated in early queries @Dao interface Dao { @RawQuery(observedEntities = MyEntry.class) LiveData<List<MyEntry>> getEntries(SupportSQLiteQuery query); } LiveData<List<User>> liveUsers = rawDao.getUsers(new SimpleSQLiteQuery("SELECT * FROM MyEntry ORDER BY name DESC"));

All magic happens at the coding stage. When you collect your project, you have classes that expand/realize Dao classes/interfees. Implementation generates a code that notifies the changes in OBD data of all interested. In the case of LiveData, the data change will be followed by a bulbeck of information where new data will come after the request is repeated due to the change room signal.The direct logic of all this can be seen in the IDE, starting with your Dao class.

RxJava has nothing to do with the life cycle of the components of the adroide of annexes. It's even made for Java in the first place, not for And, for example, AndroidSchedullers.mainThread() is not within the standard library.Anything can happen to the data, depending on how and what you do to them. You can get both memory leaks and re-established data.Usually, the challenge of re-establishing the activists is addressed through architectural libraries, where the results of the requests come into copies of special classes that do not die together with activism and re-established data when it is ready. It doesn't matter how you get the data. rxJavain AsyncTask, Thread, Retrofit, OkHtp.As a follower, you can look at RxPm or Moxy♪

Transformations.switchMap() https://developer.android.com/reference/androidx/lifecycle/Transformations