Fix crash(es) caused by failing to dispose Rx observables

app/src/main/java/fr/free/nrw/commons/CommonsApplication.java

@@ -44,6 +44,8 @@
 import fr.free.nrw.commons.upload.FileUtils;
 import fr.free.nrw.commons.utils.ConfigUtils;
 import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.internal.functions.Functions;
+import io.reactivex.plugins.RxJavaPlugins;
 import io.reactivex.schedulers.Schedulers;
 import timber.log.Timber;
 
@@ -128,6 +130,9 @@ public void onCreate() {
 
         createNotificationChannel(this);
 
+        // This handler will catch exceptions thrown from Observables after they are disposed,
+        // or from Observables that are (deliberately or not) missing an onError handler.
+        RxJavaPlugins.setErrorHandler(Functions.emptyConsumer());
 
         if (setupLeakCanary() == RefWatcher.DISABLED) {
             return;

app/src/main/java/fr/free/nrw/commons/achievements/AchievementsActivity.java

@@ -143,6 +143,12 @@ protected void onCreate(Bundle savedInstanceState) {
         initDrawer();
     }
 
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        compositeDisposable.clear();
+    }
+
     /**
      * To invoke the AlertDialog on clicking info button
      */
@@ -239,12 +245,12 @@ private void setWikidataEditCount() {
         if (StringUtils.isNullOrWhiteSpace(userName)) {
             return;
         }
-        okHttpJsonApiClient.getWikidataEdits(userName)
+        compositeDisposable.add(okHttpJsonApiClient.getWikidataEdits(userName)
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(edits -> wikidataEditsText.setText(String.valueOf(edits)), e -> {
                     Timber.e("Error:" + e);
-                });
+                }));
     }
 
     private void showSnackBarWithRetry() {

app/src/main/java/fr/free/nrw/commons/auth/AuthenticatedActivity.java

@@ -58,13 +58,12 @@ protected void onSaveInstanceState(Bundle outState) {
      * Makes API call to check if user is blocked from Commons. If the user is blocked, a snackbar
      * is created to notify the user
      */
-    protected void showBlockStatus()
-    {
-        Observable.fromCallable(() -> mediaWikiApi.isUserBlockedFromCommons())
+    protected void showBlockStatus() {
+        compositeDisposable.add(Observable.fromCallable(() -> mediaWikiApi.isUserBlockedFromCommons())
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .filter(result -> result)
                 .subscribe(result -> ViewUtil.showShortSnackbar(findViewById(android.R.id.content), R.string.block_notification)
-                );
+                ));
     }
 }

app/src/main/java/fr/free/nrw/commons/auth/LoginActivity.java

@@ -52,6 +52,7 @@
 import fr.free.nrw.commons.utils.ViewUtil;
 import io.reactivex.Observable;
 import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.disposables.CompositeDisposable;
 import io.reactivex.schedulers.Schedulers;
 import timber.log.Timber;
 
@@ -83,6 +84,7 @@ public class LoginActivity extends AccountAuthenticatorActivity {
     ProgressDialog progressDialog;
     private AppCompatDelegate delegate;
     private LoginTextWatcher textWatcher = new LoginTextWatcher();
+    private CompositeDisposable compositeDisposable = new CompositeDisposable();
 
     private Boolean loginCurrentlyInProgress = false;
     private Boolean errorMessageShown = false;
@@ -195,6 +197,7 @@ protected void onResume() {
 
     @Override
     protected void onDestroy() {
+        compositeDisposable.clear();
         try {
             // To prevent leaked window when finish() is called, see http://stackoverflow.com/questions/32065854/activity-has-leaked-window-at-alertdialog-show-method
             if (progressDialog != null && progressDialog.isShowing()) {
@@ -219,10 +222,10 @@ private void performLogin() {
         String twoFactorCode = twoFactorEdit.getText().toString();
 
         showLoggingProgressBar();
-        Observable.fromCallable(() -> login(username, password, twoFactorCode))
+        compositeDisposable.add(Observable.fromCallable(() -> login(username, password, twoFactorCode))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
-                .subscribe(result -> handleLogin(username, rawUsername, password, result));
+                .subscribe(result -> handleLogin(username, rawUsername, password, result)));
     }
 
     private String login(String username, String password, String twoFactorCode) {

app/src/main/java/fr/free/nrw/commons/bookmarks/pictures/BookmarkPicturesFragment.java

@@ -30,6 +30,7 @@
 import fr.free.nrw.commons.utils.ViewUtil;
 import io.reactivex.Observable;
 import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.disposables.CompositeDisposable;
 import io.reactivex.schedulers.Schedulers;
 import timber.log.Timber;
 
@@ -41,6 +42,7 @@ public class BookmarkPicturesFragment extends DaggerFragment {
     private static final int TIMEOUT_SECONDS = 15;
 
     private GridViewAdapter gridAdapter;
+    private CompositeDisposable compositeDisposable = new CompositeDisposable();
 
     @BindView(R.id.statusMessage) TextView statusTextView;
     @BindView(R.id.loadingImagesProgressBar) ProgressBar progressBar;
@@ -82,6 +84,12 @@ public void onStop() {
         controller.stop();
     }
 
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        compositeDisposable.clear();
+    }
+
     @Override
     public void onResume() {
         super.onResume();
@@ -113,11 +121,11 @@ private void initList() {
         progressBar.setVisibility(VISIBLE);
         statusTextView.setVisibility(GONE);
 
-        Observable.fromCallable(() -> controller.loadBookmarkedPictures())
+        compositeDisposable.add(Observable.fromCallable(() -> controller.loadBookmarkedPictures())
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
-                .subscribe(this::handleSuccess, this::handleError);
+                .subscribe(this::handleSuccess, this::handleError));
     }
 
     /**

app/src/main/java/fr/free/nrw/commons/category/CategoryImagesListFragment.java

@@ -31,6 +31,7 @@
 import fr.free.nrw.commons.utils.ViewUtil;
 import io.reactivex.Observable;
 import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.disposables.CompositeDisposable;
 import io.reactivex.schedulers.Schedulers;
 import timber.log.Timber;
 
@@ -51,6 +52,7 @@ public class CategoryImagesListFragment extends DaggerFragment {
     @BindView(R.id.loadingImagesProgressBar) ProgressBar progressBar;
     @BindView(R.id.categoryImagesList) GridView gridView;
     @BindView(R.id.parentLayout) RelativeLayout parentLayout;
+    private CompositeDisposable compositeDisposable = new CompositeDisposable();
     private boolean hasMoreImages = true;
     private boolean isLoading = true;
     private String categoryName = null;
@@ -74,6 +76,12 @@ public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
         initViews();
     }
 
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        compositeDisposable.clear();
+    }
+
     /**
      * Initializes the UI elements for the fragment
      * Setup the grid view to and scroll listener for it
@@ -109,11 +117,11 @@ private void initList() {
 
         isLoading = true;
         progressBar.setVisibility(VISIBLE);
-        Observable.fromCallable(() -> controller.getCategoryImages(categoryName))
+        compositeDisposable.add(Observable.fromCallable(() -> controller.getCategoryImages(categoryName))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
-                .subscribe(this::handleSuccess, this::handleError);
+                .subscribe(this::handleSuccess, this::handleError));
     }
 
     /**
@@ -215,11 +223,11 @@ private void fetchMoreImages() {
         }
 
         progressBar.setVisibility(VISIBLE);
-        Observable.fromCallable(() -> controller.getCategoryImages(categoryName))
+        compositeDisposable.add(Observable.fromCallable(() -> controller.getCategoryImages(categoryName))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
-                .subscribe(this::handleSuccess, this::handleError);
+                .subscribe(this::handleSuccess, this::handleError));
     }
 
     /**

app/src/main/java/fr/free/nrw/commons/category/SubCategoryListFragment.java

@@ -97,17 +97,17 @@ public void initSubCategoryList() {
         }
         progressBar.setVisibility(View.VISIBLE);
         if (!isParentCategory){
-            Observable.fromCallable(() -> mwApi.getSubCategoryList(categoryName))
+            compositeDisposable.add(Observable.fromCallable(() -> mwApi.getSubCategoryList(categoryName))
                     .subscribeOn(Schedulers.io())
                     .observeOn(AndroidSchedulers.mainThread())
                     .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
-                    .subscribe(this::handleSuccess, this::handleError);
+                    .subscribe(this::handleSuccess, this::handleError));
         }else {
-            Observable.fromCallable(() -> mwApi.getParentCategoryList(categoryName))
+            compositeDisposable.add(Observable.fromCallable(() -> mwApi.getParentCategoryList(categoryName))
                     .subscribeOn(Schedulers.io())
                     .observeOn(AndroidSchedulers.mainThread())
                     .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
-                    .subscribe(this::handleSuccess, this::handleError);
+                    .subscribe(this::handleSuccess, this::handleError));
         }
     }
 

app/src/main/java/fr/free/nrw/commons/contributions/ContributionsFragment.java

@@ -62,7 +62,6 @@
 import io.reactivex.Observable;
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.disposables.CompositeDisposable;
-import io.reactivex.disposables.Disposable;
 import io.reactivex.schedulers.Schedulers;
 import timber.log.Timber;
 
@@ -101,7 +100,6 @@ public class ContributionsFragment
     @BindView(R.id.card_view_nearby) public NearbyNotificationCardView nearbyNotificationCardView;
     @BindView(R.id.campaigns_view) CampaignView campaignView;
 
-    private Disposable placesDisposable;
     private LatLng curLatLng;
 
     private boolean firstLocationUpdate = true;
@@ -603,15 +601,15 @@ private void displayYouWontSeeNearbyMessage() {
     private void updateClosestNearbyCardViewInfo() {
         curLatLng = locationManager.getLastLocation();
 
-        placesDisposable = Observable.fromCallable(() -> nearbyController
+        compositeDisposable.add(Observable.fromCallable(() -> nearbyController
                 .loadAttractionsFromLocation(curLatLng, curLatLng, true, false)) // thanks to boolean, it will only return closest result
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(this::updateNearbyNotification,
                         throwable -> {
                             Timber.d(throwable);
                             updateNearbyNotification(null);
-                        });
+                        }));
     }
 
     private void updateNearbyNotification(@Nullable NearbyController.NearbyPlacesInfo nearbyPlacesInfo) {
@@ -648,10 +646,6 @@ public void onDestroy() {
                 isUploadServiceConnected = false;
             }
         }
-
-        if (placesDisposable != null) {
-            placesDisposable.dispose();
-        }
     }
 
     @Override

app/src/main/java/fr/free/nrw/commons/contributions/MainActivity.java

@@ -307,11 +307,11 @@ public boolean onCreateOptionsMenu(Menu menu) {
 
     @SuppressLint("CheckResult")
     private void setNotificationCount() {
-        Observable.fromCallable(() -> notificationController.getNotifications(false))
+        compositeDisposable.add(Observable.fromCallable(() -> notificationController.getNotifications(false))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(this::initNotificationViews,
-                        throwable -> Timber.e(throwable, "Error occurred while loading notifications"));
+                        throwable -> Timber.e(throwable, "Error occurred while loading notifications")));
     }
 
     private void initNotificationViews(List<Notification> notificationList) {

app/src/main/java/fr/free/nrw/commons/di/CommonsDaggerSupportFragment.java

@@ -9,18 +9,27 @@
 import dagger.android.AndroidInjector;
 import dagger.android.DispatchingAndroidInjector;
 import dagger.android.support.HasSupportFragmentInjector;
+import io.reactivex.disposables.CompositeDisposable;
 
 public abstract class CommonsDaggerSupportFragment extends Fragment implements HasSupportFragmentInjector {
 
     @Inject
     DispatchingAndroidInjector<Fragment> childFragmentInjector;
 
+    protected CompositeDisposable compositeDisposable = new CompositeDisposable();
+
     @Override
     public void onAttach(Context context) {
         inject();
         super.onAttach(context);
     }
 
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        compositeDisposable.clear();
+    }
+
     @Override
     public AndroidInjector<Fragment> supportFragmentInjector() {
         return childFragmentInjector;

app/src/main/java/fr/free/nrw/commons/explore/SearchActivity.java

@@ -98,7 +98,7 @@ public void setTabs() {
 
         viewPagerAdapter.setTabData(fragmentList, titleList);
         viewPagerAdapter.notifyDataSetChanged();
-        RxSearchView.queryTextChanges(searchView)
+        compositeDisposable.add(RxSearchView.queryTextChanges(searchView)
                 .takeUntil(RxView.detaches(searchView))
                 .debounce(500, TimeUnit.MILLISECONDS)
                 .observeOn(AndroidSchedulers.mainThread())
@@ -120,7 +120,7 @@ public void setTabs() {
                                 searchHistoryContainer.setVisibility(View.VISIBLE);
                             }
                         }
-                );
+                ));
     }
 
     /**

app/src/main/java/fr/free/nrw/commons/explore/categories/SearchCategoryFragment.java

@@ -3,7 +3,6 @@
 
 import android.content.res.Configuration;
 import android.os.Bundle;
-import android.os.Handler;
 import androidx.recyclerview.widget.GridLayoutManager;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
@@ -136,12 +135,12 @@ public void updateCategoryList(String query) {
         progressBar.setVisibility(GONE);
         queryList.clear();
         categoriesAdapter.clear();
-        Observable.fromCallable(() -> mwApi.searchCategory(query,queryList.size()))
+        compositeDisposable.add(Observable.fromCallable(() -> mwApi.searchCategory(query,queryList.size()))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
                 .doOnSubscribe(disposable -> saveQuery(query))
-                .subscribe(this::handleSuccess, this::handleError);
+                .subscribe(this::handleSuccess, this::handleError));
     }
 
 
@@ -152,11 +151,11 @@ public void addCategoriesToList(String query) {
         this.query = query;
         bottomProgressBar.setVisibility(View.VISIBLE);
         progressBar.setVisibility(GONE);
-        Observable.fromCallable(() -> mwApi.searchCategory(query,queryList.size()))
+        compositeDisposable.add(Observable.fromCallable(() -> mwApi.searchCategory(query,queryList.size()))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
-                .subscribe(this::handlePaginationSuccess, this::handleError);
+                .subscribe(this::handlePaginationSuccess, this::handleError));
     }
 
     /**