fix: prevent allow notifications prompt on rotation

app/src/main/java/org/schabi/newpipe/MainActivity.java

@@ -179,12 +179,17 @@ protected void onCreate(final Bundle savedInstanceState) {
         }
         openMiniPlayerUponPlayerStarted();
 
-        if (PermissionHelper.checkPostNotificationsPermission(this,
-                PermissionHelper.POST_NOTIFICATIONS_REQUEST_CODE)) {
-            // Schedule worker for checking for new streams and creating corresponding notifications
-            // if this is enabled by the user.
-            NotificationWorker.initialize(this);
-        }
+        PermissionHelper.checkPostNotificationsPermissionOnStartup(
+                this,
+                notificationAllowed -> {
+                    // Schedule worker for checking for new streams and creating corresponding
+                    // notifications if this is enabled by the user.
+                    if (Boolean.TRUE.equals(notificationAllowed)) {
+                        NotificationWorker.initialize(this);
+                    }
+                }
+        );
+
         if (!UpdateSettingsFragment.wasUserAskedForConsent(this)
                 && !App.getApp().isFirstRun()
                 && ReleaseVersionUtil.INSTANCE.isReleaseApk()) {

app/src/main/java/org/schabi/newpipe/util/PermissionHelper.java

@@ -1,23 +1,32 @@
 package org.schabi.newpipe.util;
 
 import android.Manifest;
+import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.content.ActivityNotFoundException;
 import android.content.Context;
 import android.content.Intent;
+import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
 import android.net.Uri;
 import android.os.Build;
 import android.provider.Settings;
 import android.widget.Toast;
 
+import androidx.activity.ComponentActivity;
+import androidx.activity.result.ActivityResultCallback;
+import androidx.activity.result.ActivityResultLauncher;
+import androidx.activity.result.contract.ActivityResultContracts;
 import androidx.annotation.RequiresApi;
 import androidx.core.app.ActivityCompat;
 import androidx.core.content.ContextCompat;
+import androidx.preference.PreferenceManager;
 
 import org.schabi.newpipe.R;
 import org.schabi.newpipe.settings.NewPipeSettings;
 
+import java.util.function.Consumer;
+
 public final class PermissionHelper {
     public static final int POST_NOTIFICATIONS_REQUEST_CODE = 779;
     public static final int DOWNLOAD_DIALOG_REQUEST_CODE = 778;
@@ -81,17 +90,59 @@ public static boolean checkWriteStoragePermissions(final Activity activity,
         return true;
     }
 
-    public static boolean checkPostNotificationsPermission(final Activity activity,
-                                                           final int requestCode) {
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU
-                && ContextCompat.checkSelfPermission(activity,
-                Manifest.permission.POST_NOTIFICATIONS)
-                != PackageManager.PERMISSION_GRANTED) {
-            ActivityCompat.requestPermissions(activity,
-                    new String[] {Manifest.permission.POST_NOTIFICATIONS}, requestCode);
-            return false;
+
+    /**
+     * Check that we have the notification permission or ask the user for permission.
+     *
+     * @param activity main activity
+     * @param userChoice a callback that gets called with the user choice
+     */
+    public static void checkPostNotificationsPermissionOnStartup(
+            final ComponentActivity activity,
+            final Consumer<Boolean> userChoice) {
+
+        // On Android before TIRAMISU, notifications are always allowed to be sent
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU) {
+            userChoice.accept(true);
+            return;
         }
-        return true;
+
+        // if we have the permission already, continue
+        if (ContextCompat.checkSelfPermission(activity, Manifest.permission.POST_NOTIFICATIONS)
+                == PackageManager.PERMISSION_GRANTED) {
+            userChoice.accept(true);
+            return;
+        }
+
+        // if we already asked the user, don’t ask again
+        final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(activity);
+        final String wasAskedKey = activity.getString(
+                R.string.user_was_asked_notification_permission_on_startup_key);
+        if (prefs.getBoolean(wasAskedKey, false)) {
+            userChoice.accept(false);
+            return;
+        }
+
+        // else let’s ask the user for permission
+        @SuppressLint("ApplySharedPref")
+        final ActivityResultCallback<Boolean> cb = isGranted -> {
+            // first make sure that we only ever ask the user once on startup
+            final SharedPreferences prefs2 =
+                    PreferenceManager.getDefaultSharedPreferences(activity);
+            // commit setting before doing anything else
+            prefs2.edit().putBoolean(wasAskedKey, true).commit();
+
+            // forward the user choice
+            userChoice.accept(isGranted);
+        };
+
+        final ActivityResultLauncher<String> notificationRequestReference =
+                activity.registerForActivityResult(
+                        new ActivityResultContracts.RequestPermission(),
+                        cb
+                );
+
+        notificationRequestReference.launch(Manifest.permission.POST_NOTIFICATIONS);
     }
 
     /**

app/src/main/res/values/settings_keys.xml

@@ -1405,6 +1405,7 @@
 
     <string name="recaptcha_cookies_key">recaptcha_cookies_key</string>
 
+    <string name="user_was_asked_notification_permission_on_startup_key">user_was_asked_notification_permission_on_startup</string>
     <string name="enable_streams_notifications">enable_streams_notifications</string>
     <string name="streams_notifications_interval_key">streams_notifications_interval</string>
     <string name="streams_notifications_interval_default">14400</string>