Observe stream of translations in PagerActivity

This patch updates PagerActivity and the InlineTranslations
functionality to observe the list of translations as they are updated
from the database. This solves issues like translations not showing up
right when they are added without returning to the menu and coming back.
Fixes #2460.

app/src/main/java/com/quran/labs/androidquran/database/TranslationsDBAdapter.kt

@@ -8,6 +8,7 @@ import com.quran.labs.androidquran.util.QuranFileUtils
 import com.quran.mobile.di.qualifier.ApplicationContext
 import com.quran.mobile.translation.data.TranslationsDataSource
 import com.quran.mobile.translation.model.LocalTranslation
+import kotlinx.coroutines.MainScope
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.filterNotNull
 import kotlinx.coroutines.flow.first
@@ -22,6 +23,8 @@ class TranslationsDBAdapter @Inject constructor(
   private val dataSource: TranslationsDataSource,
   private val quranFileUtils: QuranFileUtils
 ) {
+  private val scope = MainScope()
+
   fun getTranslations(): Flow<List<LocalTranslation>> {
     return dataSource.translations()
       .filterNotNull()

app/src/main/java/com/quran/labs/androidquran/presenter/translation/BaseTranslationPresenter.kt

@@ -21,7 +21,7 @@ import io.reactivex.rxjava3.disposables.Disposable
 import io.reactivex.rxjava3.schedulers.Schedulers
 import java.util.Collections
 
-internal open class BaseTranslationPresenter<T : Any> internal constructor(
+open class BaseTranslationPresenter<T : Any> internal constructor(
     private val translationModel: TranslationModel,
     private val translationsAdapter: TranslationsDBAdapter,
     private val translationUtil: TranslationUtil,
@@ -189,8 +189,8 @@ internal open class BaseTranslationPresenter<T : Any> internal constructor(
     }
   }
 
-  internal class ResultHolder(val translations: Array<LocalTranslation>,
-                              val ayahInformation: List<QuranAyahInfo>)
+  class ResultHolder(val translations: Array<LocalTranslation>,
+                     val ayahInformation: List<QuranAyahInfo>)
 
   override fun bind(what: T) {
     translationScreen = what

app/src/main/java/com/quran/labs/androidquran/presenter/translation/InlineTranslationPresenter.kt

@@ -0,0 +1,66 @@
+package com.quran.labs.androidquran.presenter.translation
+
+import com.quran.data.core.QuranInfo
+import com.quran.data.model.VerseRange
+import com.quran.labs.androidquran.common.QuranAyahInfo
+import com.quran.labs.androidquran.database.TranslationsDBAdapter
+import com.quran.labs.androidquran.model.translation.TranslationModel
+import com.quran.labs.androidquran.presenter.translationlist.TranslationListPresenter
+import com.quran.labs.androidquran.util.QuranSettings
+import com.quran.labs.androidquran.util.TranslationUtil
+import com.quran.mobile.translation.model.LocalTranslation
+import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers
+import io.reactivex.rxjava3.observers.DisposableSingleObserver
+import kotlinx.coroutines.MainScope
+import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.flow.onEach
+import javax.inject.Inject
+
+class InlineTranslationPresenter @Inject constructor(
+  translationModel: TranslationModel,
+  dbAdapter: TranslationsDBAdapter,
+  translationUtil: TranslationUtil,
+  private val quranSettings: QuranSettings,
+  private val translationListPresenter: TranslationListPresenter,
+  quranInfo: QuranInfo
+) : BaseTranslationPresenter<InlineTranslationPresenter.TranslationScreen>(
+  translationModel, dbAdapter, translationUtil, quranInfo
+) {
+  private val scope = MainScope()
+  private var cachedTranslations = emptyList<LocalTranslation>()
+
+  init {
+    translationListPresenter.translations()
+      .onEach { translations ->
+        cachedTranslations = translations
+        translationScreen?.onTranslationsUpdated(translations)
+      }
+      .launchIn(scope)
+  }
+
+  fun refresh(verseRange: VerseRange) {
+    disposable?.dispose()
+    disposable = getVerses(false, getTranslations(quranSettings), verseRange)
+      .observeOn(AndroidSchedulers.mainThread())
+      .subscribeWith(object : DisposableSingleObserver<ResultHolder>() {
+        override fun onSuccess(result: ResultHolder) {
+          translationScreen?.setVerses(result.translations, result.ayahInformation)
+        }
+
+        override fun onError(e: Throwable) {}
+      })
+  }
+
+  override fun bind(what: TranslationScreen) {
+    super.bind(what)
+    val translations = cachedTranslations
+    if (translations.isNotEmpty()) {
+      what.onTranslationsUpdated(translations)
+    }
+  }
+
+  interface TranslationScreen {
+    fun setVerses(translations: Array<LocalTranslation>, verses: List<QuranAyahInfo>)
+    fun onTranslationsUpdated(translations: List<LocalTranslation>)
+  }
+}

app/src/main/java/com/quran/labs/androidquran/presenter/translationlist/TranslationListPresenter.kt

@@ -14,9 +14,22 @@ import javax.inject.Inject
 class TranslationListPresenter @Inject constructor(
   private val dataSource: TranslationsDataSource
 ) {
+  private val scope = MainScope()
+
   fun translations(): Flow<List<LocalTranslation>> {
     return dataSource.translations()
       .filterNotNull()
       .map { translations -> translations.sortedBy { it.displayOrder } }
   }
+
+  fun registerForTranslations(callback: TranslationListCallback): Job {
+    return translations()
+      .onEach { translations ->
+        callback.onTranslationsUpdated(
+          titles = translations.map { translation -> translation.resolveTranslatorName() }.toTypedArray(),
+          translations = translations
+        )
+      }
+      .launchIn(scope)
+  }
 }

app/src/main/java/com/quran/labs/androidquran/ui/PagerActivity.java

@@ -21,7 +21,6 @@
 import android.os.Handler;
 import android.os.Message;
 import android.preference.PreferenceManager;
-import android.text.TextUtils;
 import android.util.SparseBooleanArray;
 import android.view.HapticFeedbackConstants;
 import android.view.KeyEvent;
@@ -68,21 +67,20 @@
 import com.quran.labs.androidquran.SearchActivity;
 import com.quran.labs.androidquran.bridge.AudioEventPresenterBridge;
 import com.quran.labs.androidquran.bridge.ReadingEventPresenterBridge;
-import com.quran.labs.androidquran.common.LocalTranslationDisplaySort;
 import com.quran.labs.androidquran.common.QuranAyahInfo;
 import com.quran.labs.androidquran.common.audio.model.QariItem;
 import com.quran.labs.androidquran.dao.audio.AudioRequest;
 import com.quran.labs.androidquran.data.Constants;
 import com.quran.labs.androidquran.data.QuranDataProvider;
 import com.quran.labs.androidquran.data.QuranDisplayData;
-import com.quran.labs.androidquran.database.TranslationsDBAdapter;
 import com.quran.labs.androidquran.di.component.activity.PagerActivityComponent;
 import com.quran.labs.androidquran.model.bookmark.BookmarkModel;
 import com.quran.labs.androidquran.model.translation.ArabicDatabaseUtils;
 import com.quran.labs.androidquran.presenter.audio.AudioPresenter;
 import com.quran.labs.androidquran.presenter.bookmark.RecentPagePresenter;
 import com.quran.labs.androidquran.presenter.data.QuranEventLogger;
 import com.quran.labs.androidquran.presenter.recitation.PagerActivityRecitationPresenter;
+import com.quran.labs.androidquran.presenter.translationlist.TranslationListPresenter;
 import com.quran.labs.androidquran.service.AudioService;
 import com.quran.labs.androidquran.service.QuranDownloadService;
 import com.quran.labs.androidquran.service.util.DefaultDownloadReceiver;
@@ -130,23 +128,21 @@
 import com.quran.reading.common.ReadingEventPresenter;
 
 import java.lang.ref.WeakReference;
-import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.concurrent.CancellationException;
 import java.util.concurrent.TimeUnit;
 
 import javax.inject.Inject;
 
 import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
 import io.reactivex.rxjava3.core.Completable;
 import io.reactivex.rxjava3.core.Observable;
-import io.reactivex.rxjava3.core.Single;
 import io.reactivex.rxjava3.disposables.CompositeDisposable;
 import io.reactivex.rxjava3.observers.DisposableObserver;
 import io.reactivex.rxjava3.observers.DisposableSingleObserver;
-import io.reactivex.rxjava3.schedulers.Schedulers;
+import kotlinx.coroutines.Job;
 import timber.log.Timber;
 
 /**
@@ -233,7 +229,6 @@ public class PagerActivity extends AppCompatActivity implements
   @Inject QuranSettings quranSettings;
   @Inject QuranScreenInfo quranScreenInfo;
   @Inject ArabicDatabaseUtils arabicDatabaseUtils;
-  @Inject TranslationsDBAdapter translationsDBAdapter;
   @Inject QuranAppUtils quranAppUtils;
   @Inject ShareUtil shareUtil;
   @Inject AudioUtils audioUtils;
@@ -248,10 +243,12 @@ public class PagerActivity extends AppCompatActivity implements
   @Inject PageViewFactoryProvider pageProviderFactoryProvider;
   @Inject Set<AyahActionFragmentProvider> additionalAyahPanels;
   @Inject PagerActivityRecitationPresenter pagerActivityRecitationPresenter;
+  @Inject TranslationListPresenter translationListPresenter;
 
   private AudioEventPresenterBridge audioEventPresenterBridge;
   private ReadingEventPresenterBridge readingEventPresenterBridge;
 
+  private Job translationJob;
   private CompositeDisposable compositeDisposable;
   private final CompositeDisposable foregroundDisposable = new CompositeDisposable();
 
@@ -543,6 +540,9 @@ public void onPageSelected(int position) {
         registerForActivityResult(new ActivityResultContracts.RequestPermission(), isGranted -> {
           audioPresenter.onPostNotificationsPermissionResponse(isGranted);
         });
+
+    // read the list of translations
+    requestTranslationsList();
   }
 
   @Override
@@ -761,9 +761,6 @@ public void onResume() {
     recentPagePresenter.bind(this);
     isInMultiWindowMode = Build.VERSION.SDK_INT >= Build.VERSION_CODES.N && isInMultiWindowMode();
 
-    // read the list of translations
-    requestTranslationsList();
-
     if (shouldReconnect) {
       foregroundDisposable.add(Completable.timer(500, TimeUnit.MILLISECONDS)
           .observeOn(AndroidSchedulers.mainThread())
@@ -971,6 +968,7 @@ public void onPause() {
     }
     recentPagePresenter.unbind(this);
     quranSettings.setWasShowingTranslation(pagerAdapter.isShowingTranslation());
+
     super.onPause();
   }
 
@@ -996,6 +994,9 @@ protected void onDestroy() {
       downloadReceiver = null;
     }
 
+    if (translationJob != null) {
+      translationJob.cancel(new CancellationException());
+    }
     currentQariBridge.unsubscribeAll();
     compositeDisposable.dispose();
     audioEventPresenterBridge.dispose();
@@ -1372,56 +1373,29 @@ private void ensurePage(int sura, int ayah) {
   }
 
   private void requestTranslationsList() {
-    compositeDisposable.add(
-        Single.fromCallable(() ->
-            translationsDBAdapter.legacyGetTranslations())
-            .subscribeOn(Schedulers.io())
-            .observeOn(AndroidSchedulers.mainThread())
-            .subscribeWith(new DisposableSingleObserver<List<LocalTranslation>>() {
-              @Override
-              public void onSuccess(@NonNull List<LocalTranslation> translationList) {
-                final List<LocalTranslation> sortedTranslations = new ArrayList<>(translationList);
-              Collections.sort(sortedTranslations, new LocalTranslationDisplaySort());
-
-              int items = sortedTranslations.size();
-                String[] titles = new String[items];
-                for (int i = 0; i < items; i++) {
-                  LocalTranslation item = sortedTranslations.get(i);
-                  if (!TextUtils.isEmpty(item.getTranslatorForeign())) {
-                    titles[i] = item.getTranslatorForeign();
-                  } else if (!TextUtils.isEmpty(item.getTranslator())) {
-                    titles[i] = item.getTranslator();
-                  } else {
-                    titles[i] = item.getName();
-                  }
-                }
-
-                Set<String> currentActiveTranslationsFilesNames = quranSettings.getActiveTranslations();
-                if (currentActiveTranslationsFilesNames.isEmpty() && items > 0) {
-                  currentActiveTranslationsFilesNames = new HashSet<>();
-                  for (int i = 0; i < items; i++) {
-                    currentActiveTranslationsFilesNames.add(sortedTranslations.get(i).getFilename());
-                  }
-                }
-                activeTranslationsFilesNames = currentActiveTranslationsFilesNames;
-
-                if (translationsSpinnerAdapter != null) {
-                  translationsSpinnerAdapter
-                      .updateItems(titles, sortedTranslations, activeTranslationsFilesNames);
-                }
-                translationNames = titles;
-                translations = sortedTranslations;
-
-                if (showingTranslation) {
-                  // Since translation items have changed, need to
-                  updateActionBarSpinner();
-                }
-              }
+    translationJob = translationListPresenter.registerForTranslations((titles, updatedTranslations) -> {
+      Set<String> currentActiveTranslationsFilesNames = quranSettings.getActiveTranslations();
+      if (currentActiveTranslationsFilesNames.isEmpty() && !updatedTranslations.isEmpty()) {
+        currentActiveTranslationsFilesNames = new HashSet<>();
+        final int items = updatedTranslations.size();
+        for (int i = 0; i < items; i++) {
+          currentActiveTranslationsFilesNames.add(updatedTranslations.get(i).getFilename());
+        }
+      }
+      activeTranslationsFilesNames = currentActiveTranslationsFilesNames;
 
-              @Override
-              public void onError(@NonNull Throwable e) {
-              }
-            }));
+      if (translationsSpinnerAdapter != null) {
+        translationsSpinnerAdapter
+            .updateItems(titles, updatedTranslations, activeTranslationsFilesNames);
+      }
+      translationNames = titles;
+      translations = updatedTranslations;
+
+      if (showingTranslation) {
+        // Since translation items have changed, need to
+        updateActionBarSpinner();
+      }
+    });
   }
 
   private void toggleBookmark(final Integer sura, final Integer ayah, final int page) {