Refactor BasePresenter

app/src/main/java/org/koitharu/kotatsu/ui/common/BasePresenter.kt

@@ -1,7 +1,44 @@
 package org.koitharu.kotatsu.ui.common
 
+import kotlinx.coroutines.*
 import moxy.MvpPresenter
-import moxy.MvpView
+import moxy.presenterScope
 import org.koin.core.component.KoinComponent
+import org.koitharu.kotatsu.BuildConfig
+import kotlin.coroutines.CoroutineContext
+import kotlin.coroutines.EmptyCoroutineContext
 
-abstract class BasePresenter<V : MvpView> : MvpPresenter<V>(), KoinComponent
+abstract class BasePresenter<V : BaseMvpView> : MvpPresenter<V>(), KoinComponent {
+
+	protected fun launchJob(
+		context: CoroutineContext = EmptyCoroutineContext,
+		start: CoroutineStart = CoroutineStart.DEFAULT,
+		block: suspend CoroutineScope.() -> Unit
+	) {
+		presenterScope.launch(context + createErrorHandler(), start, block)
+	}
+
+	protected fun launchLoadingJob(
+		context: CoroutineContext = EmptyCoroutineContext,
+		start: CoroutineStart = CoroutineStart.DEFAULT,
+		block: suspend CoroutineScope.() -> Unit
+	) {
+		presenterScope.launch(context + createErrorHandler(), start) {
+			viewState.onLoadingStateChanged(isLoading = true)
+			try {
+				block()
+			} finally {
+				viewState.onLoadingStateChanged(isLoading = false)
+			}
+		}
+	}
+
+	private fun createErrorHandler() = CoroutineExceptionHandler { _, throwable ->
+		if (BuildConfig.DEBUG) {
+			throwable.printStackTrace()
+		}
+		if (throwable !is CancellationException) {
+			viewState.onError(throwable)
+		}
+	}
+}

app/src/main/java/org/koitharu/kotatsu/ui/list/favourites/categories/FavouriteCategoriesPresenter.kt

@@ -1,13 +1,8 @@
 package org.koitharu.kotatsu.ui.list.favourites.categories
 
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
-import kotlinx.coroutines.withContext
 import moxy.InjectViewState
-import moxy.presenterScope
-import org.koitharu.kotatsu.BuildConfig
 import org.koitharu.kotatsu.core.model.Manga
 import org.koitharu.kotatsu.domain.favourites.FavouritesRepository
 import org.koitharu.kotatsu.ui.common.BasePresenter
@@ -27,130 +22,59 @@ class FavouriteCategoriesPresenter : BasePresenter<FavouriteCategoriesView>() {
 	}
 
 	fun loadAllCategories() {
-		presenterScope.launch {
+		launchJob {
-			try {
+			val categories = repository.getAllCategories()
-				val categories = withContext(Dispatchers.IO) {
-					repository.getAllCategories()
-				}
 			viewState.onCategoriesChanged(categories)
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
 		}
 	}
 
 	fun loadMangaCategories(manga: Manga) {
-		presenterScope.launch {
+		launchJob {
-			try {
+			val categories = repository.getCategories(manga.id)
-				val categories = withContext(Dispatchers.IO) {
-					repository.getCategories(manga.id)
-				}
 			viewState.onCheckedCategoriesChanged(categories.map { it.id.toInt() }.toSet())
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
 		}
 	}
 
 	fun createCategory(name: String) {
-		presenterScope.launch {
+		launchJob {
-			try {
-				val categories = withContext(Dispatchers.IO) {
 			repository.addCategory(name)
-					repository.getAllCategories()
+			val categories = repository.getAllCategories()
-				}
 			viewState.onCategoriesChanged(categories)
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
 		}
 	}
 
 	fun renameCategory(id: Long, name: String) {
-		presenterScope.launch {
+		launchJob {
-			try {
-				val categories = withContext(Dispatchers.IO) {
 			repository.renameCategory(id, name)
-					repository.getAllCategories()
+
-				}
-				viewState.onCategoriesChanged(categories)
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
 		}
 	}
 
 	fun deleteCategory(id: Long) {
-		presenterScope.launch {
+		launchJob {
-			try {
-				val categories = withContext(Dispatchers.IO) {
 			repository.removeCategory(id)
-					repository.getAllCategories()
+			val categories = repository.getAllCategories()
-				}
 			viewState.onCategoriesChanged(categories)
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
 		}
 	}
 
 	fun storeCategoriesOrder(orderedIds: List<Long>) {
-		presenterScope.launch {
+		launchJob {
-			try {
 			reorderMutex.withLock {
 				repository.reorderCategories(orderedIds)
 			}
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
 		}
 	}
 
 	fun addToCategory(manga: Manga, categoryId: Long) {
-		presenterScope.launch {
+		launchJob {
-			try {
-				withContext(Dispatchers.IO) {
 			repository.addToCategory(manga, categoryId)
 		}
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
-		}
 	}
 
 	fun removeFromCategory(manga: Manga, categoryId: Long) {
-		presenterScope.launch {
+		launchJob {
-			try {
-				withContext(Dispatchers.IO) {
 			repository.removeFromCategory(manga, categoryId)
 		}
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				viewState.onError(e)
-			}
-		}
 	}
 }

app/src/main/java/org/koitharu/kotatsu/ui/list/favourites/categories/FavouriteCategoriesView.kt

@@ -1,12 +1,12 @@
 package org.koitharu.kotatsu.ui.list.favourites.categories
 
-import moxy.MvpView
 import moxy.viewstate.strategy.AddToEndSingleStrategy
-import moxy.viewstate.strategy.OneExecutionStateStrategy
 import moxy.viewstate.strategy.StateStrategyType
+import moxy.viewstate.strategy.alias.AddToEndSingle
 import org.koitharu.kotatsu.core.model.FavouriteCategory
+import org.koitharu.kotatsu.ui.common.BaseMvpView
 
-interface FavouriteCategoriesView : MvpView {
+interface FavouriteCategoriesView : BaseMvpView {
 
 	@StateStrategyType(AddToEndSingleStrategy::class)
 	fun onCategoriesChanged(categories: List<FavouriteCategory>)
@@ -14,6 +14,6 @@ interface FavouriteCategoriesView : MvpView {
 	@StateStrategyType(AddToEndSingleStrategy::class)
 	fun onCheckedCategoriesChanged(checkedIds: Set<Int>)
 
-	@StateStrategyType(OneExecutionStateStrategy::class)
+	@AddToEndSingle
-	fun onError(e: Throwable)
+	override fun onLoadingStateChanged(isLoading: Boolean) = Unit
 }

app/src/main/java/org/koitharu/kotatsu/ui/list/local/LocalListPresenter.kt

@@ -62,8 +62,8 @@ class LocalListPresenter : BasePresenter<MangaListView<File>>() {
 	}
 
 	fun importFile(context: Context, uri: Uri) {
-		presenterScope.launch(Dispatchers.IO) {
+		launchJob {
-			try {
+			val list = withContext(Dispatchers.IO) {
 				val name = MediaStoreCompat.getName(context, uri)
 					?: throw IOException("Cannot fetch name from uri: $uri")
 				if (!LocalMangaRepository.isFileSupported(name)) {
@@ -76,25 +76,14 @@ class LocalListPresenter : BasePresenter<MangaListView<File>>() {
 						source.copyTo(output)
 					}
 				} ?: throw IOException("Cannot open input stream: $uri")
-				val list = repository.getList(0)
+				repository.getList(0)
-				withContext(Dispatchers.Main) {
-					viewState.onListChanged(list)
-				}
-			} catch (e: CancellationException) {
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-				withContext(Dispatchers.Main) {
-					viewState.onError(e)
-				}
 			}
+			viewState.onListChanged(list)
 		}
 	}
 
 	fun delete(manga: Manga) {
-		presenterScope.launch {
+		launchJob {
-			try {
 			withContext(Dispatchers.IO) {
 				val original = repository.getRemoteManga(manga)
 				repository.delete(manga) || throw IOException("Unable to delete file")
@@ -106,12 +95,6 @@ class LocalListPresenter : BasePresenter<MangaListView<File>>() {
 				MangaShortcut(manga).removeAppShortcut(get())
 			}
 			viewState.onItemRemoved(manga)
-			} catch (e: CancellationException) {
-			} catch (e: Throwable) {
-				if (BuildConfig.DEBUG) {
-					e.printStackTrace()
-				}
-			}
 		}
 	}
 }