Merge branch 'Replace_AsyncTask_with_RxJava_3' into 'master'

Replace AsyncTask implementations with RxJava 3.

See merge request fdroid/fdroidclient!947

app/build.gradle

@@ -162,9 +162,11 @@ dependencies {
     implementation 'commons-io:commons-io:2.6'
     implementation 'commons-net:commons-net:3.6'
     implementation 'ch.acra:acra:4.9.1'
-    implementation 'io.reactivex:rxjava:1.1.0'
     implementation 'com.hannesdorfmann:adapterdelegates3:3.0.1'
 
+    implementation 'io.reactivex.rxjava3:rxandroid:3.0.0'
+    implementation 'io.reactivex.rxjava3:rxjava:3.0.9'
+
     implementation 'com.fasterxml.jackson.core:jackson-core:2.11.1'
     implementation 'com.fasterxml.jackson.core:jackson-annotations:2.11.1'
     implementation 'com.fasterxml.jackson.core:jackson-databind:2.11.1'

app/proguard-rules.pro

@@ -31,13 +31,6 @@
     public *;
 }
 
-# The rxjava library depends on sun.misc.Unsafe, which is unavailable on Android
-# The rxjava team is aware of this, and mention in the docs that they only use
-# the unsafe functionality if the platform supports it.
-#  - https://github.com/ReactiveX/RxJava/issues/1415#issuecomment-48390883
-#  - https://github.com/ReactiveX/RxJava/blob/1.x/src/main/java/rx/internal/util/unsafe/UnsafeAccess.java#L23
--dontwarn rx.internal.util.**
-
 -keepattributes *Annotation*,EnclosingMethod,Signature
 -keepnames class com.fasterxml.jackson.** { *; }
 -dontwarn com.fasterxml.jackson.databind.ext.**

app/src/full/java/org/fdroid/fdroid/nearby/SwapService.java

@@ -1,6 +1,5 @@
 package org.fdroid.fdroid.nearby;
 
-import android.annotation.SuppressLint;
 import android.app.Notification;
 import android.app.PendingIntent;
 import android.app.Service;
@@ -13,11 +12,17 @@ import android.content.IntentFilter;
 import android.content.SharedPreferences;
 import android.net.Uri;
 import android.net.wifi.WifiManager;
-import android.os.AsyncTask;
 import android.os.IBinder;
 import android.text.TextUtils;
 import android.util.Log;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.core.app.NotificationCompat;
+import androidx.core.app.ServiceCompat;
+import androidx.core.content.ContextCompat;
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 import org.fdroid.fdroid.FDroidApp;
 import org.fdroid.fdroid.NotificationHelper;
 import org.fdroid.fdroid.Preferences;
@@ -30,7 +35,6 @@ import org.fdroid.fdroid.data.Schema;
 import org.fdroid.fdroid.nearby.peers.Peer;
 import org.fdroid.fdroid.net.Downloader;
 
-import java.io.IOException;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.net.HttpURLConnection;
@@ -41,13 +45,11 @@ import java.util.Set;
 import java.util.Timer;
 import java.util.TimerTask;
 
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.core.app.NotificationCompat;
-import androidx.core.app.ServiceCompat;
-import androidx.core.content.ContextCompat;
-import androidx.localbroadcastmanager.content.LocalBroadcastManager;
 import cc.mvdan.accesspoint.WifiApControl;
+import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
+import io.reactivex.rxjava3.core.Completable;
+import io.reactivex.rxjava3.disposables.CompositeDisposable;
+import io.reactivex.rxjava3.schedulers.Schedulers;
 
 /**
  * Central service which manages all of the different moving parts of swap which are required
@@ -109,46 +111,6 @@ public class SwapService extends Service {
         UpdateService.updateRepoNow(this, peer.getRepoAddress());
     }
 
-    @SuppressLint("StaticFieldLeak")
-    private void askServerToSwapWithUs(final Repo repo) {
-        new AsyncTask<Void, Void, Void>() {
-            @Override
-            protected Void doInBackground(Void... args) {
-                String swapBackUri = Utils.getLocalRepoUri(FDroidApp.repo).toString();
-                HttpURLConnection conn = null;
-                try {
-                    URL url = new URL(repo.address.replace("/fdroid/repo", "/request-swap"));
-                    conn = (HttpURLConnection) url.openConnection();
-                    conn.setRequestMethod("POST");
-                    conn.setDoInput(true);
-                    conn.setDoOutput(true);
-
-                    OutputStream outputStream = conn.getOutputStream();
-                    OutputStreamWriter writer = new OutputStreamWriter(outputStream);
-                    writer.write("repo=" + swapBackUri);
-                    writer.flush();
-                    writer.close();
-                    outputStream.close();
-
-                    int responseCode = conn.getResponseCode();
-                    Utils.debugLog(TAG, "Asking server at " + repo.address + " to swap with us in return (by " +
-                            "POSTing to \"/request-swap\" with repo \"" + swapBackUri + "\"): " + responseCode);
-                } catch (IOException e) {
-                    Log.e(TAG, "Error while asking server to swap with us", e);
-                    Intent intent = new Intent(Downloader.ACTION_INTERRUPTED);
-                    intent.setData(Uri.parse(repo.address));
-                    intent.putExtra(Downloader.EXTRA_ERROR_MESSAGE, e.getLocalizedMessage());
-                    LocalBroadcastManager.getInstance(getApplicationContext()).sendBroadcast(intent);
-                } finally {
-                    if (conn != null) {
-                        conn.disconnect();
-                    }
-                }
-                return null;
-            }
-        }.execute();
-    }
-
     private Repo ensureRepoExists(@NonNull Peer peer) {
         // TODO: newRepoConfig.getParsedUri() will include a fingerprint, which may not match with
         // the repos address in the database. Not sure on best behaviour in this situation.
@@ -342,12 +304,15 @@ public class SwapService extends Service {
     @Nullable
     private Timer timer;
 
+    private final CompositeDisposable compositeDisposable = new CompositeDisposable();
+
     public class Binder extends android.os.Binder {
         public SwapService getService() {
             return SwapService.this;
         }
     }
 
+    @Override
     public void onCreate() {
         super.onCreate();
         startForeground(NOTIFICATION, createNotification());
@@ -397,6 +362,45 @@ public class SwapService extends Service {
         BonjourManager.setVisible(this, getWifiVisibleUserPreference() || getHotspotActivatedUserPreference());
     }
 
+    private void askServerToSwapWithUs(final Repo repo) {
+        compositeDisposable.add(
+                Completable.fromAction(() -> {
+                    String swapBackUri = Utils.getLocalRepoUri(FDroidApp.repo).toString();
+                    HttpURLConnection conn = null;
+                    try {
+                        URL url = new URL(repo.address.replace("/fdroid/repo", "/request-swap"));
+                        conn = (HttpURLConnection) url.openConnection();
+                        conn.setRequestMethod("POST");
+                        conn.setDoInput(true);
+                        conn.setDoOutput(true);
+
+                        try (OutputStream outputStream = conn.getOutputStream();
+                             OutputStreamWriter writer = new OutputStreamWriter(outputStream)) {
+                            writer.write("repo=" + swapBackUri);
+                            writer.flush();
+                        }
+
+                        int responseCode = conn.getResponseCode();
+                        Utils.debugLog(TAG, "Asking server at " + repo.address + " to swap with us in return (by " +
+                                "POSTing to \"/request-swap\" with repo \"" + swapBackUri + "\"): " + responseCode);
+                    } finally {
+                        if (conn != null) {
+                            conn.disconnect();
+                        }
+                    }
+                })
+                        .subscribeOn(Schedulers.io())
+                        .observeOn(AndroidSchedulers.mainThread())
+                        .doOnError(e -> {
+                            Intent intent = new Intent(Downloader.ACTION_INTERRUPTED);
+                            intent.setData(Uri.parse(repo.address));
+                            intent.putExtra(Downloader.EXTRA_ERROR_MESSAGE, e.getLocalizedMessage());
+                            LocalBroadcastManager.getInstance(getApplicationContext()).sendBroadcast(intent);
+                        })
+                        .subscribe()
+        );
+    }
+
     /**
      * This is for setting things up for when the {@code SwapService} was
      * started by the user clicking on the initial start button. The things
@@ -420,6 +424,8 @@ public class SwapService extends Service {
 
     @Override
     public void onDestroy() {
+        compositeDisposable.dispose();
+
         Utils.debugLog(TAG, "Destroying service, will disable swapping if required, and unregister listeners.");
         Preferences.get().unregisterLocalRepoHttpsListeners(httpsEnabledListener);
         localBroadcastManager.unregisterReceiver(onWifiChange);

app/src/full/java/org/fdroid/fdroid/nearby/SwapWorkflowActivity.java

@@ -34,7 +34,18 @@ import android.widget.ProgressBar;
 import android.widget.TextView;
 import android.widget.Toast;
 
+import androidx.annotation.LayoutRes;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.annotation.StringRes;
+import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.appcompat.widget.SearchView;
+import androidx.core.content.ContextCompat;
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 import com.google.android.material.appbar.MaterialToolbar;
+import com.google.android.material.switchmaterial.SwitchMaterial;
 import com.google.zxing.integration.android.IntentIntegrator;
 import com.google.zxing.integration.android.IntentResult;
 
@@ -54,7 +65,6 @@ import org.fdroid.fdroid.net.BluetoothDownloader;
 import org.fdroid.fdroid.net.Downloader;
 import org.fdroid.fdroid.net.HttpDownloader;
 import org.fdroid.fdroid.qr.CameraCharacteristicsChecker;
-import org.fdroid.fdroid.qr.QrGenAsyncTask;
 import org.fdroid.fdroid.views.main.MainActivity;
 
 import java.util.Date;
@@ -65,17 +75,8 @@ import java.util.Set;
 import java.util.Timer;
 import java.util.TimerTask;
 
-import androidx.annotation.LayoutRes;
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.annotation.StringRes;
-import androidx.appcompat.app.AlertDialog;
-import androidx.appcompat.app.AppCompatActivity;
-import androidx.appcompat.widget.SearchView;
-import com.google.android.material.switchmaterial.SwitchMaterial;
-import androidx.core.content.ContextCompat;
-import androidx.localbroadcastmanager.content.LocalBroadcastManager;
 import cc.mvdan.accesspoint.WifiApControl;
+import io.reactivex.rxjava3.disposables.CompositeDisposable;
 
 import static org.fdroid.fdroid.views.main.MainActivity.ACTION_REQUEST_SWAP;
 
@@ -118,6 +119,8 @@ public class SwapWorkflowActivity extends AppCompatActivity {
     @LayoutRes
     private int currentSwapViewLayoutRes = STEP_INTRO;
 
+    private final CompositeDisposable compositeDisposable = new CompositeDisposable();
+
     public static void requestSwap(Context context, String repo) {
         requestSwap(context, Uri.parse(repo));
     }
@@ -235,6 +238,7 @@ public class SwapWorkflowActivity extends AppCompatActivity {
 
     @Override
     protected void onDestroy() {
+        compositeDisposable.dispose();
         localBroadcastManager.unregisterReceiver(downloaderInterruptedReceiver);
         unbindService(serviceConnection);
         super.onDestroy();
@@ -929,11 +933,14 @@ public class SwapWorkflowActivity extends AppCompatActivity {
         ImageView qrImage = container.findViewById(R.id.wifi_qr_code);
         if (qrUriString != null && qrImage != null) {
             Utils.debugLog(TAG, "Encoded swap URI in QR Code: " + qrUriString);
-            new QrGenAsyncTask(SwapWorkflowActivity.this, R.id.wifi_qr_code).execute(qrUriString);
+
+            compositeDisposable.add(Utils.generateQrBitmap(this, qrUriString)
+                    .subscribe(qrBitmap -> {
+                        qrImage.setImageBitmap(qrBitmap);
 
                         // Replace all blacks with the background blue.
-            qrImage.setColorFilter(new LightingColorFilter(0xffffffff, ContextCompat.getColor(this,
+                        qrImage.setColorFilter(new LightingColorFilter(0xffffffff,
-                    R.color.swap_blue)));
+                                ContextCompat.getColor(this, R.color.swap_blue)));
 
                         final View qrWarningMessage = container.findViewById(R.id.warning_qr_scanner);
                         if (CameraCharacteristicsChecker.getInstance(this).hasAutofocus()) {
@@ -941,6 +948,8 @@ public class SwapWorkflowActivity extends AppCompatActivity {
                         } else {
                             qrWarningMessage.setVisibility(View.VISIBLE);
                         }
+                    })
+            );
         }
     }
 

app/src/full/java/org/fdroid/fdroid/nearby/WifiStateChangeService.java

@@ -13,6 +13,10 @@ import android.os.Build;
 import android.text.TextUtils;
 import android.util.Log;
 
+import androidx.annotation.Nullable;
+import androidx.core.content.ContextCompat;
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 import org.apache.commons.net.util.SubnetUtils;
 import org.fdroid.fdroid.BuildConfig;
 import org.fdroid.fdroid.FDroidApp;
@@ -31,10 +35,8 @@ import java.security.cert.Certificate;
 import java.util.Enumeration;
 import java.util.Locale;
 
-import androidx.annotation.Nullable;
-import androidx.core.content.ContextCompat;
-import androidx.localbroadcastmanager.content.LocalBroadcastManager;
 import cc.mvdan.accesspoint.WifiApControl;
+import io.reactivex.rxjava3.disposables.CompositeDisposable;
 
 /**
  * Handle state changes to the device's wifi, storing the required bits.
@@ -70,6 +72,8 @@ public class WifiStateChangeService extends IntentService {
     private static int previousWifiState = Integer.MIN_VALUE;
     private static int wifiState;
 
+    private final CompositeDisposable compositeDisposable = new CompositeDisposable();
+
     public WifiStateChangeService() {
         super("WifiStateChangeService");
     }
@@ -82,6 +86,12 @@ public class WifiStateChangeService extends IntentService {
         context.startService(intent);
     }
 
+    @Override
+    public void onDestroy() {
+        compositeDisposable.dispose();
+        super.onDestroy();
+    }
+
     @Override
     protected void onHandleIntent(Intent intent) {
         android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_LOWEST);
@@ -109,7 +119,7 @@ public class WifiStateChangeService extends IntentService {
             }
 
             if (Build.VERSION.SDK_INT < 21 && wifiState == WifiManager.WIFI_STATE_ENABLED) {
-                UpdateService.scheduleIfStillOnWifi(this);
+                compositeDisposable.add(UpdateService.scheduleIfStillOnWifi(this).subscribe());
             }
         }
     }

app/src/main/java/org/fdroid/fdroid/UpdateService.java

@@ -30,7 +30,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.net.Uri;
-import android.os.AsyncTask;
 import android.os.Build;
 import android.os.Process;
 import android.os.SystemClock;
@@ -51,15 +50,18 @@ import org.fdroid.fdroid.installer.InstallManagerService;
 import org.fdroid.fdroid.net.BluetoothDownloader;
 import org.fdroid.fdroid.net.ConnectivityMonitorService;
 
-import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.TimeUnit;
 
 import androidx.annotation.NonNull;
 import androidx.core.app.JobIntentService;
 import androidx.core.app.NotificationCompat;
 import androidx.core.content.ContextCompat;
 import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
+import io.reactivex.rxjava3.core.Completable;
+import io.reactivex.rxjava3.schedulers.Schedulers;
 
 public class UpdateService extends JobIntentService {
 
@@ -215,42 +217,30 @@ public class UpdateService extends JobIntentService {
      * unlimited networks over metered networks for index updates and auto
      * downloads of app updates. Starting with {@code android-21}, this uses
      * {@link android.app.job.JobScheduler} instead.
+     *
+     * @return a {@link Completable} that schedules the update. If this process is already running,
+     * a {@code Completable} that completes immediately is returned.
      */
-    public static void scheduleIfStillOnWifi(Context context) {
+    @NonNull
+    public static Completable scheduleIfStillOnWifi(Context context) {
         if (Build.VERSION.SDK_INT >= 21) {
             throw new IllegalStateException("This should never be used on android-21 or newer!");
         }
         if (isScheduleIfStillOnWifiRunning || !Preferences.get().isBackgroundDownloadAllowed()) {
-            return;
+            return Completable.complete();
         }
         isScheduleIfStillOnWifiRunning = true;
-        new StillOnWifiAsyncTask(context).execute();
-    }
 
-    private static final class StillOnWifiAsyncTask extends AsyncTask<Void, Void, Void> {
+        return Completable.timer(2, TimeUnit.MINUTES)
-
+                .andThen(Completable.fromAction(() -> {
-        private final WeakReference<Context> contextWeakReference;
-
-        private StillOnWifiAsyncTask(Context context) {
-            this.contextWeakReference = new WeakReference<>(context);
-        }
-
-        @Override
-        protected Void doInBackground(Void... voids) {
-            Context context = contextWeakReference.get();
-            try {
-                Thread.sleep(120000);
                     if (Preferences.get().isBackgroundDownloadAllowed()) {
                         Utils.debugLog(TAG, "scheduling update because there is good internet");
                         schedule(context);
                     }
-            } catch (Throwable e) { // NOPMD
-                Utils.debugLog(TAG, e.getMessage());
-            }
                     isScheduleIfStillOnWifiRunning = false;
-            return null;
+                }))
-        }
+                .subscribeOn(Schedulers.computation())
-
+                .observeOn(AndroidSchedulers.mainThread());
     }
 
     public static void stopNow(Context context) {

app/src/main/java/org/fdroid/fdroid/Utils.java

@@ -27,6 +27,7 @@ import android.content.pm.Signature;
 import android.content.res.Resources;
 import android.database.Cursor;
 import android.graphics.Bitmap;
+import android.graphics.Point;
 import android.graphics.Rect;
 import android.net.Uri;
 import android.os.Build;
@@ -44,11 +45,15 @@ import android.text.style.TypefaceSpan;
 import android.util.DisplayMetrics;
 import android.util.Log;
 import android.util.TypedValue;
+import android.view.Display;
 import android.view.View;
 import android.view.ViewTreeObserver;
 import android.widget.ImageView;
 import android.widget.Toast;
 
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.encode.Contents;
+import com.google.zxing.encode.QRCodeEncoder;
 import com.nostra13.universalimageloader.core.DisplayImageOptions;
 import com.nostra13.universalimageloader.core.ImageLoader;
 import com.nostra13.universalimageloader.core.assist.ImageScaleType;
@@ -95,7 +100,11 @@ import java.util.regex.Pattern;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
+import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
+import io.reactivex.rxjava3.core.Single;
+import io.reactivex.rxjava3.schedulers.Schedulers;
 
 public final class Utils {
 
@@ -986,6 +995,27 @@ public final class Utils {
         }
     }
 
+    @NonNull
+    public static Single<Bitmap> generateQrBitmap(@NonNull final AppCompatActivity activity,
+                                                  @NonNull final String qrData) {
+        return Single.fromCallable(() -> {
+            Display display = activity.getWindowManager().getDefaultDisplay();
+            Point outSize = new Point();
+            display.getSize(outSize);
+            final int x = outSize.x;
+            final int y = outSize.y;
+            final int qrCodeDimension = Math.min(x, y);
+            debugLog(TAG, "generating QRCode Bitmap of " + qrCodeDimension + "x" + qrCodeDimension);
+            QRCodeEncoder qrCodeEncoder = new QRCodeEncoder(qrData, null,
+                    Contents.Type.TEXT, BarcodeFormat.QR_CODE.toString(), qrCodeDimension);
+
+            return qrCodeEncoder.encodeAsBitmap();
+        })
+                .subscribeOn(Schedulers.computation())
+                .observeOn(AndroidSchedulers.mainThread())
+                .doOnError(throwable -> Log.e(TAG, "Could not encode QR as bitmap", throwable));
+    }
+
     /**
      * Keep an instance of this class as an field in an AppCompatActivity for figuring out whether the on
      * screen keyboard is currently visible or not.

app/src/main/java/org/fdroid/fdroid/data/InstalledAppProviderService.java

@@ -31,9 +31,9 @@ import java.util.concurrent.TimeUnit;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.core.app.JobIntentService;
-import rx.functions.Action1;
+import io.reactivex.rxjava3.disposables.CompositeDisposable;
-import rx.schedulers.Schedulers;
+import io.reactivex.rxjava3.schedulers.Schedulers;
-import rx.subjects.PublishSubject;
+import io.reactivex.rxjava3.subjects.PublishSubject;
 
 /**
  * Handles all updates to {@link InstalledAppProvider}, whether checking the contents
@@ -65,13 +65,15 @@ public class InstalledAppProviderService extends JobIntentService {
     private static final String EXTRA_PACKAGE_INFO = "org.fdroid.fdroid.data.extra.PACKAGE_INFO";
 
     /**
-     * This is for notifing the users of this {@link android.content.ContentProvider}
+     * This is for notifying the users of this {@link android.content.ContentProvider}
-     * that the contents has changed.  Since {@link Intent}s can come in slow
+     * that the contents have changed. Since {@link Intent}s can come in slow
      * or fast, and this can trigger a lot of UI updates, the actual
      * notifications are rate limited to one per second.
      */
     private PublishSubject<String> packageChangeNotifier;
 
+    private final CompositeDisposable compositeDisposable = new CompositeDisposable();
+
     @Override
     public void onCreate() {
         super.onCreate();
@@ -81,17 +83,16 @@ public class InstalledAppProviderService extends JobIntentService {
         // only emit an event to the subscriber after it has not received any new events for one second.
         // This ensures that we don't constantly ask our lists of apps to update as we iterate over
         // the list of installed apps and insert them to the database...
+        compositeDisposable.add(
                 packageChangeNotifier
                         .subscribeOn(Schedulers.newThread())
                         .debounce(3, TimeUnit.SECONDS)
-                .subscribe(new Action1<String>() {
+                        .subscribe(packageName -> {
-                    @Override
+                            Utils.debugLog(TAG, "Notifying content providers to update relevant views.");
-                    public void call(String packageName) {
-                        Utils.debugLog(TAG, "Notifying content providers (so they can update the relevant views).");
                             getContentResolver().notifyChange(AppProvider.getContentUri(), null);
                             getContentResolver().notifyChange(ApkProvider.getContentUri(), null);
-                    }
+                        })
-                });
+        );
 
         // ...alternatively, this non-debounced version will instantly emit an event about the
         // particular package being updated. This is required so that our AppDetails view can update
@@ -100,14 +101,18 @@ public class InstalledAppProviderService extends JobIntentService {
         // only for changes to specific URIs in the AppProvider. These are triggered when a more
         // general notification (e.g. to AppProvider.getContentUri()) is fired, but not when a
         // sibling such as AppProvider.getHighestPriorityMetadataUri() is fired.
-        packageChangeNotifier.subscribeOn(Schedulers.newThread())
+        compositeDisposable.add(
-                .subscribe(new Action1<String>() {
+                packageChangeNotifier
-                    @Override
+                        .subscribeOn(Schedulers.newThread())
-                    public void call(String packageName) {
+                        .subscribe(packageName -> getContentResolver()
-                        getContentResolver()
+                                .notifyChange(AppProvider.getHighestPriorityMetadataUri(packageName), null))
-                                .notifyChange(AppProvider.getHighestPriorityMetadataUri(packageName), null);
+        );
     }
-                });
+
+    @Override
+    public void onDestroy() {
+        compositeDisposable.dispose();
+        super.onDestroy();
     }
 
     /**
@@ -243,12 +248,7 @@ public class InstalledAppProviderService extends JobIntentService {
     public static File getPathToInstalledApk(PackageInfo packageInfo) {
         File apk = new File(packageInfo.applicationInfo.publicSourceDir);
         if (apk.isDirectory()) {
-            FilenameFilter filter = new FilenameFilter() {
+            FilenameFilter filter = (dir, name) -> name.endsWith(".apk");
-                @Override
-                public boolean accept(File dir, String name) {
-                    return name.endsWith(".apk");
-                }
-            };
             File[] files = apk.listFiles(filter);
             if (files == null) {
                 String msg = packageInfo.packageName + " sourceDir has no APKs: " + apk.getAbsolutePath();

app/src/main/java/org/fdroid/fdroid/qr/QrGenAsyncTask.java

@@ -1,74 +0,0 @@
-package org.fdroid.fdroid.qr;
-
-import android.annotation.TargetApi;
-import android.graphics.Bitmap;
-import android.graphics.Point;
-import android.os.AsyncTask;
-import android.util.Log;
-import android.view.Display;
-import android.widget.ImageView;
-
-import com.google.zxing.BarcodeFormat;
-import com.google.zxing.WriterException;
-import com.google.zxing.encode.Contents;
-import com.google.zxing.encode.QRCodeEncoder;
-
-import org.fdroid.fdroid.Utils;
-
-import androidx.appcompat.app.AppCompatActivity;
-
-public class QrGenAsyncTask extends AsyncTask<String, Void, Void> {
-    private static final String TAG = "QrGenAsyncTask";
-
-    private final AppCompatActivity activity;
-    private final int viewId;
-    private Bitmap qrBitmap;
-
-    public QrGenAsyncTask(AppCompatActivity activity, int viewId) {
-        this.activity = activity;
-        this.viewId = viewId;
-    }
-
-    /*
-     * The method for getting screen dimens changed, so this uses both the
-     * deprecated one and the 13+ one, and supports all Android versions.
-     */
-    @SuppressWarnings("deprecation")
-    @TargetApi(13)
-    @Override
-    protected Void doInBackground(String... s) {
-        String qrData = s[0];
-        Display display = activity.getWindowManager().getDefaultDisplay();
-        Point outSize = new Point();
-        int x, y, qrCodeDimension;
-        display.getSize(outSize);
-        x = outSize.x;
-        y = outSize.y;
-        if (x < y) {
-            qrCodeDimension = x;
-        } else {
-            qrCodeDimension = y;
-        }
-        Utils.debugLog(TAG, "generating QRCode Bitmap of " + qrCodeDimension + "x" + qrCodeDimension);
-        QRCodeEncoder qrCodeEncoder = new QRCodeEncoder(qrData, null,
-                Contents.Type.TEXT, BarcodeFormat.QR_CODE.toString(), qrCodeDimension);
-
-        try {
-            qrBitmap = qrCodeEncoder.encodeAsBitmap();
-        } catch (WriterException e) {
-            Log.e(TAG, "Could not encode QR as bitmap", e);
-        }
-        return null;
-    }
-
-    @Override
-    protected void onPostExecute(Void v) {
-        ImageView qrCodeImageView = (ImageView) activity.findViewById(viewId);
-
-        // If the generation takes too long for whatever reason, then this view, and indeed the entire
-        // activity may not be around any more.
-        if (qrCodeImageView != null) {
-            qrCodeImageView.setImageBitmap(qrBitmap);
-        }
-    }
-}

app/src/main/java/org/fdroid/fdroid/views/ManageReposActivity.java

@@ -19,7 +19,6 @@
 
 package org.fdroid.fdroid.views;
 
-import android.annotation.SuppressLint;
 import android.content.ClipData;
 import android.content.ClipboardManager;
 import android.content.ContentResolver;
@@ -32,13 +31,13 @@ import android.database.Cursor;
 import android.net.Uri;
 import android.net.wifi.WifiInfo;
 import android.net.wifi.WifiManager;
-import android.os.AsyncTask;
 import android.os.Build;
 import android.os.Bundle;
 import android.text.Editable;
 import android.text.TextUtils;
 import android.text.TextWatcher;
 import android.util.Log;
+import android.util.Pair;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
@@ -50,17 +49,6 @@ import android.widget.ListView;
 import android.widget.TextView;
 import android.widget.Toast;
 
-import androidx.annotation.NonNull;
-import androidx.appcompat.app.AlertDialog;
-import androidx.appcompat.app.AppCompatActivity;
-import androidx.appcompat.widget.Toolbar;
-import androidx.core.app.NavUtils;
-import androidx.core.app.TaskStackBuilder;
-import androidx.core.content.ContextCompat;
-import androidx.loader.app.LoaderManager;
-import androidx.loader.content.CursorLoader;
-import androidx.loader.content.Loader;
-
 import com.google.android.material.appbar.MaterialToolbar;
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import com.google.android.material.textfield.TextInputLayout;
@@ -87,6 +75,22 @@ import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Locale;
 
+import androidx.annotation.NonNull;
+import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.appcompat.widget.Toolbar;
+import androidx.core.app.NavUtils;
+import androidx.core.app.TaskStackBuilder;
+import androidx.core.content.ContextCompat;
+import androidx.loader.app.LoaderManager;
+import androidx.loader.content.CursorLoader;
+import androidx.loader.content.Loader;
+import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
+import io.reactivex.rxjava3.core.Single;
+import io.reactivex.rxjava3.disposables.CompositeDisposable;
+import io.reactivex.rxjava3.disposables.Disposable;
+import io.reactivex.rxjava3.schedulers.Schedulers;
+
 public class ManageReposActivity extends AppCompatActivity
         implements LoaderManager.LoaderCallbacks<Cursor>, RepoAdapter.EnabledListener {
     private static final String TAG = "ManageReposActivity";
@@ -107,6 +111,8 @@ public class ManageReposActivity extends AppCompatActivity
      */
     private boolean finishAfterAddingRepo;
 
+    private final CompositeDisposable compositeDisposable = new CompositeDisposable();
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         FDroidApp fdroidApp = (FDroidApp) getApplication();
@@ -154,6 +160,12 @@ public class ManageReposActivity extends AppCompatActivity
         });
     }
 
+    @Override
+    protected void onDestroy() {
+        compositeDisposable.dispose();
+        super.onDestroy();
+    }
+
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         MenuInflater menuInflater = getMenuInflater();
@@ -571,10 +583,8 @@ public class ManageReposActivity extends AppCompatActivity
         /**
          * Adds a new repo to the database.
          */
-        @SuppressLint("StaticFieldLeak")
         private void prepareToCreateNewRepo(final String originalAddress, final String fingerprint,
                                             final String username, final String password) {
-
             final View addRepoForm = addRepoDialog.findViewById(R.id.add_repo_form);
             addRepoForm.setVisibility(View.GONE);
             final View positiveButton = addRepoDialog.getButton(AlertDialog.BUTTON_POSITIVE);
@@ -586,84 +596,65 @@ public class ManageReposActivity extends AppCompatActivity
             final Button skip = addRepoDialog.getButton(AlertDialog.BUTTON_NEGATIVE);
             skip.setText(R.string.skip);
 
-            final AsyncTask<String, String, String> checker = new AsyncTask<String, String, String>() {
+            final int refreshDialog = Integer.MAX_VALUE;
-
+            final Disposable disposable = Single.fromCallable(() -> {
-                private int statusCode = -1;
+                int statusCode = -1;
-                private static final int REFRESH_DIALOG = Integer.MAX_VALUE;
-
-                @Override
-                protected String doInBackground(String... params) {
-                    final String originalAddress = params[0];
 
                 if (fingerprintRepoMap.containsKey(fingerprint)) {
-                        statusCode = REFRESH_DIALOG;
+                    statusCode = refreshDialog;
-                        return originalAddress;
+                    return Pair.create(statusCode, originalAddress);
                 }
 
                 if (originalAddress.startsWith(ContentResolver.SCHEME_CONTENT)
                         || originalAddress.startsWith(ContentResolver.SCHEME_FILE)) {
                     // TODO check whether there is read access
-                        return originalAddress;
+                    return Pair.create(statusCode, originalAddress);
                 }
 
                 final String[] pathsToCheck = {"", "fdroid/repo", "repo"};
                 for (final String path : pathsToCheck) {
-
                     Utils.debugLog(TAG, "Check for repo at " + originalAddress + " with suffix '" + path + "'");
                     Uri.Builder builder = Uri.parse(originalAddress).buildUpon().appendEncodedPath(path);
                     final String addressWithoutIndex = builder.build().toString();
-                        publishProgress(addressWithoutIndex);
+                    runOnUiThread(() -> textSearching.setText(getString(R.string.repo_searching_address,
+                            addressWithoutIndex)));
 
                     if (urlRepoMap.containsKey(addressWithoutIndex)) {
-                            statusCode = REFRESH_DIALOG;
+                        statusCode = refreshDialog;
-                            return addressWithoutIndex;
+                        return Pair.create(statusCode, addressWithoutIndex);
                     }
 
                     final Uri uri = builder.appendPath(IndexUpdater.SIGNED_FILE_NAME).build();
 
                     try {
-                            if (checkForRepository(uri)) {
+                        final URL url = new URL(uri.toString());
-                                Utils.debugLog(TAG, "Found F-Droid repo at " + addressWithoutIndex);
-                                return addressWithoutIndex;
-                            }
-                        } catch (IOException e) {
-                            Log.e(TAG, "Error while searching for repo at " + addressWithoutIndex, e);
-                            return originalAddress;
-                        }
-
-                        if (isCancelled()) {
-                            Utils.debugLog(TAG, "Not checking more repo addresses, because process was skipped.");
-                            break;
-                        }
-                    }
-                    return originalAddress;
-
-                }
-
-                private boolean checkForRepository(Uri indexUri) throws IOException {
-                    final URL url = new URL(indexUri.toString());
                         final HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                         connection.setRequestMethod("HEAD");
 
                         statusCode = connection.getResponseCode();
 
-                    return statusCode == HttpURLConnection.HTTP_UNAUTHORIZED
+                        if (statusCode == HttpURLConnection.HTTP_UNAUTHORIZED
-                            || statusCode == HttpURLConnection.HTTP_OK;
+                                || statusCode == HttpURLConnection.HTTP_OK) {
+                            Utils.debugLog(TAG, "Found F-Droid repo at " + addressWithoutIndex);
+                            return Pair.create(statusCode, addressWithoutIndex);
                         }
-
+                    } catch (IOException e) {
-                @Override
+                        Log.e(TAG, "Error while searching for repo at " + addressWithoutIndex, e);
-                protected void onProgressUpdate(String... values) {
+                        return Pair.create(statusCode, originalAddress);
-                    String address = values[0];
-                    textSearching.setText(getString(R.string.repo_searching_address, address));
                     }
-
+                }
-                @Override
+                return Pair.create(statusCode, originalAddress);
-                protected void onPostExecute(final String newAddress) {
+            })
+                    .subscribeOn(Schedulers.io())
+                    .observeOn(AndroidSchedulers.mainThread())
+                    .doOnDispose(() -> Utils.debugLog(TAG,
+                            "Not checking more repo addresses, because process was skipped."))
+                    .subscribe(codeAddressPair -> {
+                        final int statusCode = codeAddressPair.first;
+                        final String newAddress = codeAddressPair.second;
 
                         if (addRepoDialog.isShowing()) {
-
                             if (statusCode == HttpURLConnection.HTTP_UNAUTHORIZED) {
-
                                 final View view = getLayoutInflater().inflate(R.layout.login, null);
                                 final AlertDialog credentialsDialog = new AlertDialog.Builder(context)
                                         .setView(view).create();
@@ -679,30 +670,20 @@ public class ManageReposActivity extends AppCompatActivity
 
                                 credentialsDialog.setTitle(R.string.login_title);
                                 credentialsDialog.setButton(DialogInterface.BUTTON_NEGATIVE,
-                                    getString(R.string.cancel),
+                                        getString(R.string.cancel), (dialog, which) -> {
-                                    new DialogInterface.OnClickListener() {
-                                        @Override
-                                        public void onClick(DialogInterface dialog, int which) {
                                             dialog.dismiss();
                                             // cancel parent dialog, don't add repo
                                             addRepoDialog.cancel();
-                                        }
                                         });
 
                                 credentialsDialog.setButton(DialogInterface.BUTTON_POSITIVE,
                                         getString(R.string.ok),
-                                    new DialogInterface.OnClickListener() {
+                                        (dialog, which) -> createNewRepo(newAddress, fingerprint,
-                                        @Override
-                                        public void onClick(DialogInterface dialog, int which) {
-                                            createNewRepo(newAddress, fingerprint,
                                                 nameInput.getText().toString(),
-                                                    passwordInput.getText().toString());
+                                                passwordInput.getText().toString()));
-                                        }
-                                    });
 
                                 credentialsDialog.show();
-
+                            } else if (statusCode == refreshDialog) {
-                        } else if (statusCode == REFRESH_DIALOG) {
                                 addRepoForm.setVisibility(View.VISIBLE);
                                 positiveButton.setVisibility(View.VISIBLE);
                                 textSearching.setText("");
@@ -710,29 +691,22 @@ public class ManageReposActivity extends AppCompatActivity
                                 skip.setOnClickListener(null);
                                 validateRepoDetails(newAddress, fingerprint);
                             } else {
-
                                 // create repo without username/password
                                 createNewRepo(newAddress, fingerprint);
                             }
                         }
-                }
+                    });
-            };
+            compositeDisposable.add(disposable);
 
-            skip.setOnClickListener(new View.OnClickListener() {
+            skip.setOnClickListener(v -> {
-                @Override
-                public void onClick(View v) {
                 // Still proceed with adding the repo, just don't bother searching for
                 // a better alternative than the one provided.
                 // The reason for this is that if they are not connected to the internet,
                 // or their internet is playing up, then you'd have to wait for several
                 // connection timeouts before being able to proceed.
-
                 createNewRepo(originalAddress, fingerprint);
-                    checker.cancel(false);
+                disposable.dispose();
-                }
             });
-
-            checker.execute(originalAddress);
         }
 
         /**

app/src/main/java/org/fdroid/fdroid/views/RepoDetailsActivity.java

@@ -23,6 +23,7 @@ import android.view.ViewGroup;
 import android.widget.Button;
 import android.widget.CompoundButton;
 import android.widget.EditText;
+import android.widget.ImageView;
 import android.widget.TextView;
 import android.widget.Toast;
 
@@ -38,7 +39,6 @@ import org.fdroid.fdroid.Utils;
 import org.fdroid.fdroid.data.Repo;
 import org.fdroid.fdroid.data.RepoProvider;
 import org.fdroid.fdroid.data.Schema.RepoTable;
-import org.fdroid.fdroid.qr.QrGenAsyncTask;
 
 import java.util.Arrays;
 import java.util.HashSet;
@@ -52,6 +52,7 @@ import androidx.core.content.ContextCompat;
 import androidx.localbroadcastmanager.content.LocalBroadcastManager;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
+import io.reactivex.rxjava3.disposables.Disposable;
 
 public class RepoDetailsActivity extends AppCompatActivity {
     private static final String TAG = "RepoDetailsActivity";
@@ -91,6 +92,8 @@ public class RepoDetailsActivity extends AppCompatActivity {
 
     private MirrorAdapter adapterToNotify;
 
+    private Disposable disposable;
+
     /**
      * Help function to make switching between two view states easier.
      * Perhaps there is a better way to do this. I recall that using Adobe
@@ -141,7 +144,19 @@ public class RepoDetailsActivity extends AppCompatActivity {
         Uri uri = Uri.parse(repo.address);
         uri = uri.buildUpon().appendQueryParameter("fingerprint", repo.fingerprint).build();
         String qrUriString = uri.toString();
-        new QrGenAsyncTask(this, R.id.qr_code).execute(qrUriString);
+        disposable = Utils.generateQrBitmap(this, qrUriString)
+                .subscribe(bitmap -> {
+                    final ImageView qrCode = findViewById(R.id.qr_code);
+                    if (qrCode != null) {
+                        qrCode.setImageBitmap(bitmap);
+                    }
+                });
+    }
+
+    @Override
+    protected void onDestroy() {
+        disposable.dispose();
+        super.onDestroy();
     }
 
     @TargetApi(14)

gradle/verification-metadata.xml

@@ -16,7 +16,10 @@
             <trusting group="commons-collections" name="commons-collections" version="3.2.2"/>
          </trusted-key>
          <trusted-key id="19beab2d799c020f17c69126b16698a4adf4d638" group="org.checkerframework" name="checker-qual" version="2.5.2"/>
-         <trusted-key id="1d9aa7f9e1e2824728b8cd1794b291aef984a085" group="io.reactivex" name="rxjava" version="1.1.0"/>
+         <trusted-key id="1d9aa7f9e1e2824728b8cd1794b291aef984a085">
+            <trusting group="io.reactivex" name="rxjava" version="1.1.0"/>
+            <trusting group="io.reactivex.rxjava3"/>
+         </trusted-key>
          <trusted-key id="280bcdfa20225ff340f9e3a2fb52acb341119b0a" group="com.nostra13.universalimageloader" name="universal-image-loader" version="1.9.5"/>
          <trusted-key id="2bab4466b44f54f8f99bbbdd5ed22f661bbf0acc" group="com.almworks.sqlite4java" name="sqlite4java" version="0.282"/>
          <trusted-key id="2db4f1ef0fa761ecc4ea935c86fdc7e2a11262cb">
@@ -2702,6 +2705,11 @@
             <sha256 value="207839ab1011448bae3886fc36b6cb9fff1f5b3fa5f10cc79d242cee9dc1c3de" origin="Generated by Gradle"/>
          </artifact>
       </component>
+      <component group="org.reactivestreams" name="reactive-streams" version="1.0.3">
+         <artifact name="reactive-streams-1.0.3.jar">
+            <pgp value="a33a0b49a4c1ab590b0a4ddc1364c5e2df3e99c5"/>
+         </artifact>
+      </component>
       <component group="org.robolectric" name="annotations" version="4.3">
          <artifact name="annotations-4.3.jar">
             <sha256 value="8c10ec1a43ea8346b094a08eaf0aefbaaf749e1a80f10de6a70e7f8788735d03" origin="Generated by Gradle"/>