Ask for permission before using Bluetooth

src/main/AndroidManifest.xml

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 -->
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
     package="de.dennisguse.opentracks"
     android:installLocation="auto">
 
@@ -52,7 +53,10 @@ limitations under the License.
     <uses-permission
         android:name="android.permission.BLUETOOTH_ADMIN"
         android:maxSdkVersion="30" />
-    <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
+    <uses-permission
+        android:name="android.permission.BLUETOOTH_SCAN"
+        android:usesPermissionFlags="neverForLocation"
+        tools:targetApi="s" />
     <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
 
     <application

src/main/java/de/dennisguse/opentracks/settings/bluetooth/BluetoothLeSensorPreference.java

@@ -1,5 +1,6 @@
 package de.dennisguse.opentracks.settings.bluetooth;
 
+import android.Manifest;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.le.BluetoothLeScanner;
 import android.bluetooth.le.ScanCallback;
@@ -8,6 +9,8 @@ import android.bluetooth.le.ScanResult;
 import android.bluetooth.le.ScanSettings;
 import android.content.Context;
 import android.content.DialogInterface;
+import android.content.pm.PackageManager;
+import android.os.Build;
 import android.os.Bundle;
 import android.os.ParcelUuid;
 import android.text.TextUtils;
@@ -15,7 +18,10 @@ import android.util.AttributeSet;
 import android.util.Log;
 import android.widget.Toast;
 
+import androidx.activity.result.ActivityResultLauncher;
+import androidx.activity.result.contract.ActivityResultContracts;
 import androidx.appcompat.app.AlertDialog;
+import androidx.core.content.ContextCompat;
 import androidx.preference.DialogPreference;
 import androidx.preference.PreferenceDialogFragmentCompat;
 import androidx.vectordrawable.graphics.drawable.AnimatedVectorDrawableCompat;
@@ -143,13 +149,39 @@ public abstract class BluetoothLeSensorPreference extends DialogPreference {
         public void onCreate(Bundle savedInstanceState) {
             super.onCreate(savedInstanceState);
 
-            List<ParcelUuid> serviceUUIDs = getArguments().getParcelableArrayList(ARG_BLE_SERVICE_UUIDS);
-
             // Don't know why: need to load the drawable _twice_, so that animation is actually started.
             bluetoothIcon = AnimatedVectorDrawableCompat.create(getContext(), R.drawable.ic_bluetooth_searching_animated_24dp);
             bluetoothIcon = AnimatedVectorDrawableCompat.create(getContext(), R.drawable.ic_bluetooth_searching_animated_24dp);
             bluetoothIcon.start();
 
+            if (
+                    Build.VERSION.SDK_INT >= Build.VERSION_CODES.S && (
+                            ContextCompat.checkSelfPermission(getContext(), Manifest.permission.BLUETOOTH_SCAN) != PackageManager.PERMISSION_GRANTED ||
+                                    ContextCompat.checkSelfPermission(getContext(), Manifest.permission.BLUETOOTH_CONNECT) != PackageManager.PERMISSION_GRANTED
+                    )
+            ) {
+                ActivityResultLauncher<String[]> requestPermissionLauncher =
+                        registerForActivityResult(new ActivityResultContracts.RequestMultiplePermissions(), granted -> {
+                            if (!granted.containsValue(false)) {
+                                startBluetoothScan();
+                            } else if (shouldShowRequestPermissionRationale(Manifest.permission.BLUETOOTH_SCAN) || shouldShowRequestPermissionRationale(Manifest.permission.BLUETOOTH_CONNECT)) {
+                                Toast.makeText(getContext(), R.string.permission_bluetooth_failed_rejected, Toast.LENGTH_LONG).show();
+                                dismiss();
+                            } else {
+                                Toast.makeText(getContext(), R.string.permission_bluetooth_failed, Toast.LENGTH_SHORT).show();
+                                dismiss();
+                            }
+                        });
+
+                requestPermissionLauncher.launch(new String[]{Manifest.permission.BLUETOOTH_CONNECT, Manifest.permission.BLUETOOTH_SCAN});
+            } else {
+                startBluetoothScan();
+            }
+        }
+
+        private void startBluetoothScan() {
+            List<ParcelUuid> serviceUUIDs = getArguments().getParcelableArrayList(ARG_BLE_SERVICE_UUIDS);
+
             BluetoothAdapter bluetoothAdapter = BluetoothUtils.getAdapter(getContext());
             if (bluetoothAdapter == null || !bluetoothAdapter.isEnabled()) {
                 Log.w(TAG, "Bluetooth adapter is present or not enabled.");

src/main/res/values-de/strings.xml

@@ -1,5 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
+<?xml version="1.0" encoding="utf-8"?><!--
 Copyright 2010 Google Inc.
 
 Licensed under the Apache License, Version 2.0 (the "License");
@@ -13,7 +12,8 @@ distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
---><resources>
+-->
+<resources>
     <string name="about_preference_title">Über OpenTracks</string>
     <string name="about_description"><i>OpenTracks</i> ist eine Sport-Tracking-Anwendung, die Ihre Privatsphäre vollständig respektiert.</string>
     <string name="about_url">Projekt-Website: <a href="%1$s">%1$s</a></string>
@@ -235,6 +235,8 @@ Meldet das GPS-Gerät ungenaue Daten (z.B. Standort, Geschwindigkeit, Höhe), ka
     <string name="recording_service">Dienst für Aufzeichnung</string>
     <!-- Permission -->
     <string name="permission_gps_failed">OpenTracks benötigt eine Berechtigung zur Nutzung von GPS.</string>
+    <string name="permission_bluetooth_failed">OpenTracks benötigt eine Berechtigung zur Nutzung von Bluetooth.</string>
+    <string name="permission_bluetooth_failed_rejected">Du musst OpenTracks die Berechtigung zum Zugriff auf Geräte in der Nähe manuell in den Systemeinstellungen geben.</string>
     <!-- Search -->
     <!-- Sensor State -->
     <string name="sensor_state_battery">Akkustatus</string>

src/main/res/values/strings.xml

@@ -309,6 +309,8 @@ limitations under the License.
     <string name="delete_service">Deletion service</string>
     <!-- Permission -->
     <string name="permission_gps_failed">OpenTracks requires permission to use GPS.</string>
+    <string name="permission_bluetooth_failed">OpenTracks requires permission to use Bluetooth.</string>
+    <string name="permission_bluetooth_failed_rejected">You manually need to grant OpenTracks access to Nearby Devices in system settings.</string>
     <!-- Search -->
     <!-- Sensor State -->
     <string name="sensor_state_battery">Battery level</string>