Changing toolbar title in each fragment using MVVM and Databinding - android

I am looking to change the toolbar title,which is in my main activity, in my fragments page. My project is based on MVVM Architecture, with databinding.
This is my main_activity.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="viewModel"
type="com.lalsoft.toolbar_mvvm_databinding.viewmodel.MainViewModel" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".view.MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:elevation="0dp"
android:theme="#style/AppTheme.AppBarOverlay">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:minHeight="?attr/actionBarSize"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:titleTextColor="#android:color/white"
app:navigationIcon="#drawable/ic_arrow_back"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay"
app:navigationOnClickListener="#{()->viewModel.navBackClicked()}"
app:title="#{viewModel.toolbarTitle}"/>
</com.google.android.material.appbar.AppBarLayout>
<FrameLayout
android:id="#+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
This is my mainActivity.kt
private const val TAG = "MainActivity"
class MainActivity : AppCompatActivity() {
private lateinit var viewModel: MainViewModel
private lateinit var dataBinding: ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
dataBinding = DataBindingUtil.setContentView(this, R.layout.activity_main)
viewModel = ViewModelProvider(this).get(MainViewModel::class.java)
//setSupportActionBar(dataBinding.toolbar)
//dataBinding.toolbar.setNavigationIcon(R.drawable.ic_arrow_back)
viewModel.navClicked.observe(this, navClickObserver)
viewModel.toolbarTitle.observe(this, toolbarTitleObserver)
dataBinding.viewModel = viewModel
if (savedInstanceState == null) {
supportFragmentManager.beginTransaction().replace(
R.id.fragment_container,
FirstFragment()
).commit()
}
}
private val navClickObserver = Observer<Boolean> {
supportFragmentManager.popBackStack()
Log.e(TAG, "Nav Back clicked")
}
private val toolbarTitleObserver = Observer<String> {
Log.e(TAG, "Title set : $it")
}
}
And this is my MainViewModel
private const val TAG = "MainViewModel"
open class MainViewModel : ViewModel() {
val toolbarTitle: MutableLiveData<String> = MutableLiveData()
private val _navClicked: MutableLiveData<Boolean> = MutableLiveData()
val navClicked: LiveData<Boolean> = _navClicked
init {
Log.e(TAG, "Inside Init")
//toolbarTitle.value ="Main Activity"
}
fun navBackClicked() {
_navClicked.value = true
}
}
Now i am trying to change the toolbar title in FragmentViewModel by changing the mutable toolbarTitle of my mainActivityViewModel.
private const val TAG = "FirstViewModel"
class FirstViewModel : MainViewModel() {
private val _navigateToDetails = MutableLiveData<Event<String>>()
val navigateToFragment: LiveData<Event<String>>
get() = _navigateToDetails
init {
Log.e(TAG, "Inside Init")
toolbarTitle.value="First Fragment"
}
fun onBtnClick() {
_navigateToDetails.value = Event("Second Fragment")
}
}
This is my fragment class
private const val TAG = "FirstFragment"
class FirstFragment : Fragment() {
private lateinit var viewModel: FirstViewModel
private lateinit var dataBinding: FirstFragmentBinding
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
dataBinding = DataBindingUtil.inflate(inflater, R.layout.first_fragment, container, false)
return dataBinding.root
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
viewModel = ViewModelProvider(this).get(FirstViewModel::class.java)
viewModel.toolbarTitle.observe(viewLifecycleOwner, toolbarTitleObserver)
viewModel.navigateToFragment.observe(viewLifecycleOwner, navigateToFragmentObserver)
//(activity as MainActivity?)!!.toolbar.title = "Check"
dataBinding.viewModel = viewModel
}
private val toolbarTitleObserver = Observer<String> {
Log.e(TAG, "Title set : $it")
//(activity as MainActivity?)!!.toolbar.title = "Check"
//Log.e(TAG, "Title set : Check")
}
private val navigateToFragmentObserver = Observer<Event<String>> { it ->
it.getContentIfNotHandled()?.let { // Only proceed if the event has never been handled
Log.i(TAG, "checkIt string $it")
parentFragmentManager.beginTransaction().replace(
R.id.fragment_container,
SecondFragment()
).addToBackStack(null).commit()
}
}
}
Eventhough its observing the toolbarTitle correctly,the Title in my program is not changing..
Hope to get some help to get out of this issue.
This is my sample git project where i am trying to do this : github

I struggle with the same!
I think the problem is the lifecycleowner. But could not find an answer.
Currently I observe the values from the the ViewModel and assign the values inside the observer.
But I think there is a better way!

If your Fragment is using a ViewModel should be scoped to a host Activity, use by activityViewModels() delegate:
#AndroidEntryPoint
class HomeFragment : Fragment() {
private val viewModel: SharedViewModel by activityViewModels()
}
I think also this answer will help.
https://stackoverflow.com/a/62560605
When you use by viewModels, you are creating a ViewModel scoped to that individual Fragment - this means each Fragment will have its own individual instance of that ViewModel class. If you want a single ViewModel instance scoped to the entire Activity, you'd want to use by activityViewModels

Related

Binding Adapter live data value is always null

For some reason, the second parameter value for both binding Adapters always returns null and I cannot figure out why. I am selecting a plantIndividual from a RecyclerView in the overview fragment and using it to navigate to a details page - individual fragment. Both Fragments share a viewModel.
Here are my BindingAdapters:
#BindingAdapter("listPhotoData")
fun bindPlantRecyclerView(recyclerView: RecyclerView,
data: List<PlantPhoto>?) {
val adapter = recyclerView.adapter as CollectionIndividualAdapter
adapter.submitList(data)
}
#BindingAdapter("singleImage")
fun loadImage(imgView: ImageView, imgUrl: File) {
imgUrl.let {
Glide.with(imgView.context)
.load(imgUrl)
.apply(
RequestOptions()
.placeholder(R.drawable.loading_animation)
.error(R.drawable.ic_broken_image))
.into(imgView)
}
}
My details fragment layout:
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="viewModel"
type="com.example.collection.presentation.overview.CollectionOverviewViewModel" />
<variable
name="plantPhoto"
type="com.example.storage.data.PlantPhoto" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true">
<ImageView
android:id="#+id/collection_individual_imageview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:singleImage="#={viewModel.plantPhotoDisplay.plantFilePath}"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.26999998"
tools:srcCompat="#tools:sample/avatars" />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/collection_individual_recyclerview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layoutManager="androidx.recyclerview.widget.GridLayoutManager"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/collection_individual_imageview"
app:layout_constraintVertical_bias="0.498"
app:listPhotoData="#={viewModel.listPlantPhoto}"
tools:listitem="#layout/image_plant_photo_view" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
ViewModel:
class CollectionOverviewViewModel(application: Application) : AndroidViewModel(application) {
lateinit var mediaPlantList: MutableList<File>
private var newPhotoList = mutableListOf<PlantPhoto>()
private val context = getApplication<Application>().applicationContext
private val _navigateToSelectedPlant = MutableLiveData<PlantIndividual>()
val navigateToSelectedPlant: LiveData<PlantIndividual>
get() = _navigateToSelectedPlant
private val _listPlantPhoto = MutableLiveData<MutableList<PlantPhoto>>()
val listPlantPhoto: LiveData<MutableList<PlantPhoto>>
get() = _listPlantPhoto
private val _plantPhotoDisplay = MutableLiveData<PlantPhoto>()
val plantPhotoDisplay: LiveData<PlantPhoto>
get() = _plantPhotoDisplay
fun displayPlantDetails(plantIndividual: PlantIndividual) {
_navigateToSelectedPlant.value = plantIndividual
}
fun displayPlantDetailsComplete() {
_navigateToSelectedPlant.value = null
}
fun retrievePlantList(plantIndividual: PlantIndividual) {
val dataClassNum = plantIndividual.plantId
viewModelScope.launch {
mediaPlantList = context?.getExternalFilesDir("planio/dataclasses/$dataClassNum")
?.listFiles()?.sortedDescending()?.toMutableList() ?: mutableListOf()
}
}
fun changeToPlantPhotos(plantList: MutableList<File>) {
plantList.map {
val file = FileInputStream(it)
val inStream = ObjectInputStream(file)
val item = inStream.readObject() as PlantPhoto
newPhotoList.add(item)
}
_plantPhotoDisplay.value = newPhotoList.last()
_listPlantPhoto.value = newPhotoList
}
}
OverView Fragment from which I am selecting a plantIndividual from a RecyclerView and navigating to a details page:
viewModel.navigateToSelectedPlant.observe(viewLifecycleOwner, {
if (null != it) {
viewModel.retrievePlantList(it)
viewModel.changeToPlantPhotos(viewModel.mediaPlantList)
this.findNavController().navigate(
CollectionOverviewFragmentDirections.
actionCollectionOverviewFragmentToCollectionIndividualFragment(it))
}
})
Details Fragment:
class CollectionIndividualFragment: Fragment() {
private lateinit var binding: FragmentCollectionIndividualBinding
private val viewModel: CollectionOverviewViewModel by viewModels()
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
binding = DataBindingUtil.inflate(inflater, R.layout.fragment_collection_individual, container,
false)
binding.toCollectionOverview.setOnClickListener {
this.findNavController().navigate(CollectionIndividualFragmentDirections.
actionCollectionIndividualFragmentToCollectionOverviewFragment())
viewModel.displayPlantDetailsComplete()
}
binding.viewModel = viewModel
binding.lifecycleOwner = this
binding.collectionIndividualRecyclerview.adapter = CollectionIndividualAdapter()
binding.plantPhoto = viewModel.plantPhotoDisplay.value
return binding.root
}
I guess you're setting the lifecycleOwner after setting the viewModel of your binding and as a result, after viewModel is set in binding, it cannot observe live data because the lifecycleOwner is null at that point. I suggest to set it after setting binding
binding = DataBindingUtil.inflate(inflater, R.layout.fragment_collection_individual, container,
false)
binding.lifecycleOwner = this
Edit:
Also don't forget to use by activityViewModels instead of by viewModels to share viewModel among your fragments

Android: LiveData postValue() getting null

I am trying to transfer a value from one LiveData (Repository.getMovieList(editTextContent.value.toString()).value) to another LiveData (this.movieList.postValue) using postValue().
I am observing the movieList and want to change it's value from the Repo depending on different buttons that were clicked but I when it runs, it only gets the null value and doesn't wait till the Repo's LiveData gets their value.
Fragment xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="viewmodel"
type="com.example.movieapp.ui.search.SearchMovieFragmentViewModel" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".ui.search.SearchMovieFragment">
<EditText
android:id="#+id/search_movie_edit_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#={viewmodel.editTextContent}"
android:inputType="text"
android:hint="Movie Name" />
<Button
android:id="#+id/search_fragment_search_btn"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Search"
android:onClick="#{() -> viewmodel.getMovieSearchList()}"/>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/search_movie_fragment_recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
</layout>
SearchMovieFragment
class SearchMovieFragment : Fragment(), MovieSearchItemViewModel {
companion object {
fun newInstance() = SearchMovieFragment()
}
private lateinit var searchMovieFragmentViewModel: SearchMovieFragmentViewModel
private lateinit var binding: SearchMovieFragmentBinding
private lateinit var movieRecyclerView: RecyclerView
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
binding = DataBindingUtil.inflate(inflater, R.layout.search_movie_fragment, container, false)
searchMovieFragmentViewModel = ViewModelProvider(this).get(SearchMovieFragmentViewModel::class.java)
binding.lifecycleOwner = this
binding.viewmodel = searchMovieFragmentViewModel
setUpRecyclerView(container!!.context)
return binding.root
}
private fun setUpRecyclerView(context: Context) {
movieRecyclerView = binding.searchMovieFragmentRecyclerView.apply {
this.layoutManager = LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false)
}
val adapter = MovieListAdapter()
adapter.setCallback(this)
binding.searchMovieFragmentRecyclerView.adapter = adapter
searchMovieFragmentViewModel.getMovieListLiveData().observe(viewLifecycleOwner, Observer {movieList ->
adapter.submitList(movieList)
})
}
}
SearchMovieViewModel
class SearchMovieFragmentViewModel : ViewModel() {
val editTextContent = MutableLiveData<String>()
var movieList: MutableLiveData<List<Movie>> = MutableLiveData()
fun getMovieSearchList(){
this.movieList.postValue(Repository.getMovieList(editTextContent.value.toString()).value)
}
fun getTrendingMovies() {
movieList.postValue(Repository.getTrendingMovies().value)
}
fun getMovieDetail(movieId: String): MutableLiveData<Movie> {
return Repository.getMovieDetail(movieId)
}
fun getMovieListLiveData() : LiveData<List<Movie>> {
return movieList
}
private fun getMovieList(movieSearch: String): MutableLiveData<List<Movie>> = Repository.getMovieList(movieSearch)
}
I think you are implementing it the wrong way, Instead, using the MediatorLiveData will be a good and practical solution as it allows you to observe multiple LiveData objects and select between them based on your preferences (a specific action for example).
This is an example of how to implement it in your case
val editTextContent = MutableLiveData<String>()
val finalList = MediatorLiveData<List<Movie>>()
// Here.. Define all of your LiveData objects
private val movieList = repository.getMovieList(editTextContent.value.toString())
private val trendingMovies = repository.getTrendingMovies()
private val movieDetail = repository.getMovieDetail()
fun setSelection(selection: String) {
finalList.addSource(movieList) { result ->
if (selection == "movieList") {
result?.let { finalList.value = it }
}
}
finalList.addSource(trendingMovies) { result ->
if (selection == "trendingMovies") {
result?.let { finalList.value = it }
}
}
finalList.addSource(movieDetail) { result ->
if (selection == "movieDetail") {
result?.let { finalList.value = it }
}
}
}
So what you have to do is to only observe the MediatorLiveData and then call the setSelection function and send the correspondent selection action to it as a parameter and it will switch the observation to another LiveData

DialogFragment with view model not working with data binding

I've created one dialog fragemnt with view model (mvvm). Dialog consist of one button (custom view). when using view model with data binding, button click is not working when livedata change.I'm using boolean value to check if button is clicked or not. What is causing issue? Also suggest any other approach if needed.
profile_dialog_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="viewmodel"
type="com.test.ui.ProfileDialogViewModel" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.ProfileDialog">
<com.google.android.material.button.MaterialButton
android:id="#+id/login"
style="#style/TextAppearance.MaterialComponents.Button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login"
android:onClick="#{() -> viewmodel.onLoginButtonClick()}"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
ProfileDialog.kt
class ProfileDialog : DialogFragment() {
companion object {
fun newInstance() = ProfileDialog()
}
private val viewModel: ProfileDialogViewModel by viewModel()
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val binding = ProfileDialogFragmentBinding.inflate(inflater, container, false)
.apply {
this.lifecycleOwner = this#ProfileDialog
this.viewmodel = viewmodel
}
return binding.root
}
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
viewModel.startLogin.observe(viewLifecycleOwner, Observer {
Log.d("insta", "This is working")
if (it == null) return#Observer
if(it) {
Log.d("insta", "This is not working")
val loginIntent = Intent(this.context, LoginActivity::class.java)
this.context?.startActivity(loginIntent)
}
})
}
}
ProfileDialogViewModel.kt
class ProfileDialogViewModel : ViewModel() {
private val _startLogin = MutableLiveData<Boolean>(false)
val startLogin: LiveData<Boolean>
get() = _startLogin
fun onLoginButtonClick() {
Log.d("insta", "This ain't working")
_startLogin.postValue(true)
}
}
Your viewmodel is defined in
private val viewModel: ProfileDialogViewModel by viewModel()
So, pay attention to viewModel. The problem located in
this.viewmodel = viewmodel
where this points to ProfileDialogFragmentBinding. Here you assinging ProfileDialogFragmentBinding.viewmodel = ProfileDialogFragmentBinding.viewmodel - that's why it's not working.
To solve problem, properly assign it like that:
this.viewmodel = viewModel

Data binding returning null

I might be doing this all wrong, but I have the same exact implementation in another fragment/viewmodel with no problems. Maybe because it's a dialog? Every time I log message or message.messagebody it returns null. Can anyone maybe point out why? Currently learning mvvm.
xml: (the important bit since it's long)
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="user"
type="com.catbellystudio.knodee.models.Users" />
<variable
name="vm"
type="com.catbellystudio.knodee.ui.profile.ProfileViewModel" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="400dp"
android:layout_margin="10dp"
android:background="#drawable/custom_background_popup"
android:elevation="10dp"
android:orientation="vertical">
<ScrollView
android:id="#+id/popupTextLayout"
android:layout_width="match_parent"
android:layout_height="277dp"
android:layout_marginTop="8dp">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/colorPrimary"
android:hint="#string/your_message"
android:inputType="textMultiLine"
android:padding="10dp"
android:text="#{vm.message.messageBody}" />
</ScrollView>
</LinearLayout>
</layout>
viewmodel:
class ProfileViewModel(
private val userRepository: UserRepository,
private val messageRepository: MessageRepository
) : ViewModel() {
var message: Message = Message()
var sender: Users? = null
var receiver: Users? = null
var string:String?=null
fun getLoggedInUser() = runBlocking { userRepository.getUser() }
fun onBackPressed(view: View) {
Navigation.findNavController(view).navigateUp()
}
fun postMessage(view:View) {
Coroutines.main {
Log.e("messagevm", message.toString())
}
}
}
fragment:
class MessageFragment : Fragment(), KodeinAware {
private lateinit var viewModel: ProfileViewModel
private lateinit var profileBinding: FragmentProfileBinding
private lateinit var popupBinding: FragmentPopupBinding
override val kodein by kodein()
private val factory: ProfileViewModelFactory by instance()
private lateinit var dialog: Dialog
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
viewModel = ViewModelProviders.of(this, factory).get(ProfileViewModel::class.java)
profileBinding = DataBindingUtil.inflate(
inflater,
R.layout.fragment_profile,
container,
false
)
popupBinding = FragmentPopupBinding.inflate(LayoutInflater.from(context))
dialog = context?.let { Dialog(it) }!!
dialog.setContentView(popupBinding.root)
dialog.window?.setBackgroundDrawableResource(android.R.color.transparent)
profileBinding.viewModel = viewModel
popupBinding.vm = viewModel
getSender()
return profileBinding.root
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
settingsButtonProfile.visibility = View.GONE
messageButtonProfile.setOnClickListener {
showPopUp()
}
val receiver by lazy {
arguments?.let { fromBundle(it).user }
}
viewModel.receiver = receiver
}
private fun showPopUp() {
dialog.show()
val switch = dialog.visibilitySwitchPopup
val visibilityTextView = dialog.visibilityTextViewPopup
dialog.closeButtonPopUp?.setOnClickListener {
dialog.dismiss()
}
switch?.setOnClickListener {
val isIconEnabled = switch.isIconEnabled
if (isIconEnabled) {
visibilityTextView?.text = getString(R.string.anonymous_prompt)
} else {
visibilityTextView?.text = getString(R.string.anonymous_warning)
}
switch.switchState()
}
}
private fun getSender() {
viewModel.getLoggedInUser()?.let { viewModel.sender = it }
}
}
Any help would be appreciated!
move this "popupBinding.vm = viewModel" line to onViewCreated() method and also include this line "popupBinding.lifeCycleOwner=this" in same method
Solved by changing
android:text="#{vm.message.messageBody}
to
android:text="#={vm.message.messageBody}

Android View Model binding in kotlin

i am facing a strange issue. I am binding a viewModel to my layout by factory design patter. When ever i build that there is difference between inferred and expected view model.
My View Model Class
class SleepTrackerViewModel(
val database: SleepDatabaseDao,
application: Application) : AndroidViewModel(application) {
private var viewModelJob = Job()
private val uiScope = CoroutineScope(Dispatchers.Main + viewModelJob)
var alarmList = database.getAllAlarms()
override fun onCleared() {
super.onCleared()
viewModelJob.cancel()
}
fun onStartTracking() {
uiScope.launch {
val newNight = AlarmModel()
insert(newNight)
}
}
private suspend fun insert(night: AlarmModel) {
withContext(Dispatchers.IO) {
database.insert(night)
}
}
}
So when every i try to assign the view model in fragment, it shows error that expected and inferred view model are different
My XML file
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<data>
<variable
name="viewModel"
type="com.example.android.trackmysleepquality.Fragments.SleepTrackerViewModel" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- TODO: Update blank fragment layout -->
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
app:listData="#{viewModel.alarmList}" />
</LinearLayout>
</layout>
My Factory Class
class SleepTrackerViewModelFactory(
private val dataSource: SleepDatabaseDao,
private val application: Application) : ViewModelProvider.Factory {
#Suppress("unchecked_cast")
override fun <T : ViewModel?> create(modelClass: Class<T>): T {
if (modelClass.isAssignableFrom(SleepTrackerViewModel::class.java)) {
return SleepTrackerViewModel(dataSource, application) as T
}
throw IllegalArgumentException("Unknown ViewModel class")
}
}
Remove ViewModel from your XML file and try this one.
class AddMovieFragment : Fragment() {
private lateinit var viewModel: AddMovieViewModel
companion object {
const val SEARCH_QUERY = "SEARCH_QUERY"
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
viewModel = ViewModelProviders.of(this).get(AddMovieViewModel::class.java)
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?): View {
return inflater.inflate(R.layout.fragment_add_movie, container, false)
}

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