Refactor LiveData extensions

app/src/main/java/org/koitharu/kotatsu/details/ui/DetailsViewModel.kt

@@ -106,14 +106,14 @@ class DetailsViewModel(
 	val branches: LiveData<List<String?>> = delegate.manga.map {
 		val chapters = it?.chapters ?: return@map emptyList()
 		chapters.mapToSet { x -> x.branch }.sortedWith(BranchComparator())
-	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, emptyList())
 
 	val selectedBranchIndex = combine(
 		branches.asFlow(),
 		delegate.selectedBranch
 	) { branches, selected ->
 		branches.indexOf(selected)
-	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, -1)
 
 	val isChaptersEmpty: LiveData<Boolean> = combine(
 		delegate.manga,

app/src/main/java/org/koitharu/kotatsu/favourites/ui/categories/select/MangaCategoriesViewModel.kt

@@ -26,7 +26,7 @@ class MangaCategoriesViewModel(
 				isChecked = it.id in checked
 			)
 		}
-	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, emptyList())
 
 	fun setChecked(categoryId: Long, isChecked: Boolean) {
 		launchJob(Dispatchers.Default) {

app/src/main/java/org/koitharu/kotatsu/main/ui/MainViewModel.kt

@@ -2,9 +2,6 @@ package org.koitharu.kotatsu.main.ui
 
 import androidx.lifecycle.viewModelScope
 import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.flow.filter
-import kotlinx.coroutines.flow.map
-import kotlinx.coroutines.flow.onStart
 import org.koitharu.kotatsu.base.ui.BaseViewModel
 import org.koitharu.kotatsu.core.exceptions.EmptyHistoryException
 import org.koitharu.kotatsu.core.prefs.AppSection
@@ -41,13 +38,7 @@ class MainViewModel(
 
 	val isResumeEnabled = historyRepository
 		.observeHasItems()
-		.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+		.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, false)
-
-	val remoteSources = settings.observe()
-		.filter { it == AppSettings.KEY_SOURCES_ORDER || it == AppSettings.KEY_SOURCES_HIDDEN }
-		.onStart { emit("") }
-		.map { settings.getMangaSources(includeHidden = false) }
-		.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
 
 	fun openLastReader() {
 		launchLoadingJob {

app/src/main/java/org/koitharu/kotatsu/reader/ui/ReaderActivity.kt

@@ -347,8 +347,12 @@ class ReaderActivity :
 		menuItem.setIcon(if (isAdded) R.drawable.ic_bookmark_added else R.drawable.ic_bookmark)
 	}
 
-	private fun onUiStateChanged(uiState: ReaderUiState, previous: ReaderUiState?) {
+	private fun onUiStateChanged(uiState: ReaderUiState?, previous: ReaderUiState?) {
-		title = uiState.chapterName ?: uiState.mangaName ?: getString(R.string.loading_)
+		title = uiState?.chapterName ?: uiState?.mangaName ?: getString(R.string.loading_)
+		if (uiState == null) {
+			supportActionBar?.subtitle = null
+			return
+		}
 		supportActionBar?.subtitle = if (uiState.chapterNumber in 1..uiState.chaptersTotal) {
 			getString(R.string.chapter_d_of_d, uiState.chapterNumber, uiState.chaptersTotal)
 		} else {

app/src/main/java/org/koitharu/kotatsu/reader/ui/ReaderViewModel.kt

@@ -64,7 +64,7 @@ class ReaderViewModel(
 	val readerMode = MutableLiveData<ReaderMode>()
 	val onPageSaved = SingleLiveEvent<Uri?>()
 	val onShowToast = SingleLiveEvent<Int>()
-	val uiState = combine(
+	val uiState: LiveData<ReaderUiState?> = combine(
 		mangaData,
 		currentState,
 	) { manga, state ->
@@ -75,7 +75,7 @@ class ReaderViewModel(
 			chapterNumber = chapter?.number ?: 0,
 			chaptersTotal = chapters.size()
 		)
-	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, null)
 
 	val content = MutableLiveData(ReaderContent(emptyList(), null))
 	val manga: Manga?
@@ -93,7 +93,7 @@ class ReaderViewModel(
 	) { manga, policy ->
 		policy == ScreenshotsPolicy.BLOCK_ALL ||
 			(policy == ScreenshotsPolicy.BLOCK_NSFW && manga != null && manga.isNsfw)
-	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, false)
 
 	val onZoomChanged = SingleLiveEvent<Unit>()
 
@@ -105,7 +105,7 @@ class ReaderViewModel(
 			bookmarksRepository.observeBookmark(manga, state.chapterId, state.page)
 				.map { it != null }
 		}
-	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, false)
 
 	init {
 		loadImpl()

app/src/main/java/org/koitharu/kotatsu/settings/onboard/OnboardDialogFragment.kt

@@ -14,7 +14,6 @@ import org.koitharu.kotatsu.base.ui.list.OnListItemClickListener
 import org.koitharu.kotatsu.databinding.DialogOnboardBinding
 import org.koitharu.kotatsu.settings.onboard.adapter.SourceLocalesAdapter
 import org.koitharu.kotatsu.settings.onboard.model.SourceLocale
-import org.koitharu.kotatsu.utils.ext.observeNotNull
 import org.koitharu.kotatsu.utils.ext.showAllowStateLoss
 import org.koitharu.kotatsu.utils.ext.withArgs
 
@@ -56,8 +55,8 @@ class OnboardDialogFragment :
 		val adapter = SourceLocalesAdapter(this)
 		binding.recyclerView.adapter = adapter
 		binding.textViewTitle.setText(R.string.onboard_text)
-		viewModel.list.observeNotNull(viewLifecycleOwner) {
+		viewModel.list.observe(viewLifecycleOwner) {
-			adapter.items = it
+			adapter.items = it.orEmpty()
 		}
 	}
 

app/src/main/java/org/koitharu/kotatsu/settings/protect/ProtectSetupViewModel.kt

@@ -17,7 +17,7 @@ class ProtectSetupViewModel(
 
 	val isSecondStep = firstPassword.map {
 		it != null
-	}.asLiveDataDistinct(viewModelScope.coroutineContext)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext, false)
 	val onPasswordSet = SingleLiveEvent<Unit>()
 	val onPasswordMismatch = SingleLiveEvent<Unit>()
 	val onClearText = SingleLiveEvent<Unit>()

app/src/main/java/org/koitharu/kotatsu/utils/ext/LiveDataExt.kt

@@ -2,7 +2,6 @@ package org.koitharu.kotatsu.utils.ext
 
 import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.LiveData
-import androidx.lifecycle.Observer
 import androidx.lifecycle.liveData
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.StateFlow
@@ -10,14 +9,6 @@ import org.koitharu.kotatsu.utils.BufferedObserver
 import kotlin.coroutines.CoroutineContext
 import kotlin.coroutines.EmptyCoroutineContext
 
-fun <T> LiveData<T?>.observeNotNull(owner: LifecycleOwner, observer: Observer<T>) {
-	this.observe(owner) {
-		if (it != null) {
-			observer.onChanged(it)
-		}
-	}
-}
-
 fun <T> LiveData<T>.requireValue(): T = checkNotNull(value) {
 	"LiveData value is null"
 }
@@ -30,17 +21,6 @@ fun <T> LiveData<T>.observeWithPrevious(owner: LifecycleOwner, observer: Buffere
 	}
 }
 
-@Deprecated("Use variant with default value")
-fun <T> Flow<T>.asLiveDataDistinct(
-	context: CoroutineContext = EmptyCoroutineContext
-): LiveData<T> = liveData(context) {
-	collect {
-		if (it != latestValue) {
-			emit(it)
-		}
-	}
-}
-
 fun <T> StateFlow<T>.asLiveDataDistinct(
 	context: CoroutineContext = EmptyCoroutineContext
 ): LiveData<T> = asLiveDataDistinct(context, value)
@@ -48,7 +28,7 @@ fun <T> StateFlow<T>.asLiveDataDistinct(
 fun <T> Flow<T>.asLiveDataDistinct(
 	context: CoroutineContext = EmptyCoroutineContext,
 	defaultValue: T
-): LiveData<T> = liveData(context, 0L) {
+): LiveData<T> = liveData(context) {
 	if (latestValue == null) {
 		emit(defaultValue)
 	}
@@ -57,18 +37,4 @@ fun <T> Flow<T>.asLiveDataDistinct(
 			emit(it)
 		}
 	}
-}
-
-fun <T> Flow<T>.asLiveDataDistinct(
-	context: CoroutineContext = EmptyCoroutineContext,
-	defaultValue: suspend () -> T
-): LiveData<T> = liveData(context) {
-	if (latestValue == null) {
-		emit(defaultValue())
-	}
-	collect {
-		if (it != latestValue) {
-			emit(it)
-		}
-	}
 }

app/src/main/java/org/koitharu/kotatsu/widget/shelf/ShelfConfigViewModel.kt

@@ -1,5 +1,6 @@
 package org.koitharu.kotatsu.widget.shelf
 
+import androidx.lifecycle.LiveData
 import androidx.lifecycle.viewModelScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -8,7 +9,6 @@ import org.koitharu.kotatsu.base.ui.BaseViewModel
 import org.koitharu.kotatsu.favourites.domain.FavouritesRepository
 import org.koitharu.kotatsu.utils.ext.asLiveDataDistinct
 import org.koitharu.kotatsu.widget.shelf.model.CategoryItem
-import java.util.*
 
 class ShelfConfigViewModel(
 	favouritesRepository: FavouritesRepository
@@ -16,7 +16,7 @@ class ShelfConfigViewModel(
 
 	private val selectedCategoryId = MutableStateFlow(0L)
 
-	val content = combine(
+	val content: LiveData<List<CategoryItem>> = combine(
 		favouritesRepository.observeCategories(),
 		selectedCategoryId
 	) { categories, selectedId ->
@@ -26,7 +26,7 @@ class ShelfConfigViewModel(
 			CategoryItem(it.id, it.title, selectedId == it.id)
 		}
 		list
-	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default)
+	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, emptyList())
 
 	var checkedId: Long by selectedCategoryId::value
 }