Some more improvements for Android permissions

qbluetoothleuartclient.cpp

@@ -30,28 +30,81 @@ QBluetoothLeUartClient::~QBluetoothLeUartClient(){
 // - Slots for QBluetoothLeUart -
 // ------------------------------
 
+bool QBluetoothLeUartClient::requestLocationPermission() {
+
+    if(this->isLocationPermissionGranted())
+        return true;
+
+#ifdef Q_OS_ANDROID
+    // try to get permission
+    QtAndroid::PermissionResultMap resultMap = QtAndroid::requestPermissionsSync({"android.permission.ACCESS_FINE_LOCATION", "android.permission.ACCESS_COARSE_LOCATION"});
+    bool resultBool = true;
+    for(QtAndroid::PermissionResult result : resultMap) {
+        if(result != QtAndroid::PermissionResult::Granted) {
+            resultBool = false;
+        }
+    }
+
+    if(resultBool) {
+        if(this->state == LocationPermissionDenied)
+            this->setState(Idle);
+        return true;
+    }
+
+    // getting permission the traditional way failed -> open the settings app
+    QAndroidJniObject activity = QAndroidJniObject::callStaticObjectMethod("org/qtproject/qt5/android/QtNative", "activity", "()Landroid/app/Activity;");   //activity is valid
+    if (activity.isValid())
+    {
+        // get the package name
+        QAndroidJniObject context = QtAndroid::androidContext();
+        QAndroidJniObject applicationPackageName = context.callObjectMethod<jstring>("getPackageName");
+
+        QAndroidJniObject param = QAndroidJniObject::fromString("package:" + applicationPackageName.toString());
+
+        // Equivalent to Jave code: 'Uri uri = Uri::parse("...");'
+        QAndroidJniObject uri = QAndroidJniObject::callStaticObjectMethod("android/net/Uri", "parse", "(Ljava/lang/String;)Landroid/net/Uri;", param.object<jstring>());
+        if (!uri.isValid()) {
+            qWarning("ERROR: Unable to create Uri object");
+            return false;
+        }
+        QAndroidJniObject packageName = QAndroidJniObject::fromString("android.settings.APPLICATION_DETAILS_SETTINGS");
+
+        QAndroidJniObject intent("android/content/Intent","(Ljava/lang/String;)V", packageName.object<jstring>());
+        if (!intent.isValid()) {
+            qWarning("ERROR: Unable to create Intent object");
+            return false;
+        }
+        intent.callObjectMethod("addCategory", "(Ljava/lang/String;)Landroid/content/Intent;", QAndroidJniObject::fromString("android.intent.category.DEFAULT").object<jstring>());
+        intent.callObjectMethod("setData", "(Landroid/net/Uri;)Landroid/content/Intent;", uri.object<jobject>());
+
+        activity.callMethod<void>("startActivity","(Landroid/content/Intent;)V",intent.object<jobject>());
+    }
+    else {
+        qWarning() << "ERROR: Activity not valid!";
+        return false;
+    }
+
+    return true;
+#else
+    return false;
+#endif
+
+}
+
+bool QBluetoothLeUartClient::isLocationPermissionGranted() {
+#ifdef Q_OS_ANDROID
+    QtAndroid::PermissionResult fineLocationAccess = QtAndroid::checkPermission("android.permission.ACCESS_FINE_LOCATION");
+    QtAndroid::PermissionResult coarseLocationAccess = QtAndroid::checkPermission("android.permission.ACCESS_COARSE_LOCATION");
+
+    return fineLocationAccess == QtAndroid::PermissionResult::Granted && coarseLocationAccess == QtAndroid::PermissionResult::Granted;
+#else
+    return true;
+#endif
+}
+
 bool QBluetoothLeUartClient::startScanningForDevices(){
     if(this->state != Idle && this->state != AdapterTurnedOff && this->state != ScanFinished && this->state != LocationPermissionDenied)
         return false;
-#ifdef Q_OS_ANDROID
-    else if(this->state == LocationPermissionDenied) {
-        // try to get permission
-        QtAndroid::PermissionResultMap resultMap = QtAndroid::requestPermissionsSync({"android.permission.ACCESS_FINE_LOCATION", "android.permission.ACCESS_COARSE_LOCATION"});
-        bool resultBool = true;
-        for(QtAndroid::PermissionResult result : resultMap) {
-             if(result != QtAndroid::PermissionResult::Granted) {
-                 resultBool = false;
-                 break;
-             }
-        }
-
-        if(!resultBool) {
-            emit this->scanningErrorOccured(LocationPermissionDeniedError);
-            return false;
-        }
-
-    }
-#endif
 
     this->availableDevicesModel->clear();
 
@@ -233,20 +286,15 @@ void QBluetoothLeUartClient::handleDeviceScanError(QBluetoothDeviceDiscoveryAgen
         this->setState(AdapterTurnedOff);
         emit this->scanningErrorOccured(InputOutputError);
     }
-#ifdef Q_OS_ANDROID
     else if (error == QBluetoothDeviceDiscoveryAgent::UnknownError) {
         // check for permission error
-        QtAndroid::PermissionResult fineLocationAccess = QtAndroid::checkPermission("android.permission.ACCESS_FINE_LOCATION");
+        if(!this->isLocationPermissionGranted()) {
-        QtAndroid::PermissionResult coarseLocationAccess = QtAndroid::checkPermission("android.permission.ACCESS_COARSE_LOCATION");
-
-        if(fineLocationAccess != QtAndroid::PermissionResult::Granted || coarseLocationAccess != QtAndroid::PermissionResult::Granted) {
             this->setState(LocationPermissionDenied);
             emit this->scanningErrorOccured(LocationPermissionDeniedError);
         }
         else
             emit this->scanningErrorOccured(UnknownError);
     }
-#endif
     else
         emit this->scanningErrorOccured(UnknownError);
 
@@ -372,7 +420,7 @@ void QBluetoothLeUartClient::handleServiceCharacteristicChange(const QLowEnergyC
 }
 
 void QBluetoothLeUartClient::handleServiceDescriptorWritten(const QLowEnergyDescriptor &d,
-                                                     const QByteArray &value)
+                                                            const QByteArray &value)
 {
     if (d.isValid() && d == bluetoothTransmissionDescriptor && value == QByteArray("0000")) {
         //disabled notifications -> assume disconnect intent

qbluetoothleuartclient.h

@@ -192,6 +192,10 @@ private:
 
 public slots:
 
+    Q_INVOKABLE bool requestLocationPermission();
+
+    Q_INVOKABLE bool isLocationPermissionGranted();
+
     /*!
      * \brief Fuction to start scanning for devices
      *