Added option to check service status

CHANGELOG.md

+## 2.2.0
+
+* Added new method `checkServiceStatus` to allow users to check if the location services (on Android and iOS) and motion services (iOS only) are enabled;
+* When checking permission status (using `checkPermissionStatus`) return `PermissionStatus.disabled` when permissions are granted or denied and the location services (on Android and iOS) or the motion services (iOS only) are disabled.
+
 ## 2.1.3
 ## 2.1.3
 
 
 * Fixed bug on iOS where result of the `openAppSettings` call always returned `false`;
 * Fixed bug on iOS where result of the `openAppSettings` call always returned `false`;

README.md

@@ -22,7 +22,7 @@ To use this plugin, add `permission_handler` as a [dependency in your pubspec.ya
 
 
 ```yaml
 ```yaml
 dependencies:
 dependencies:
-  permission_handler: '^2.1.3'
+  permission_handler: '^2.2.0'
 ```
 ```
 
 
 > **NOTE:** There's a known issue with integrating plugins that use Swift into a Flutter project created with the Objective-C template. See issue [Flutter#16049](https://github.com/flutter/flutter/issues/16049) for help on integration.
 > **NOTE:** There's a known issue with integrating plugins that use Swift into a Flutter project created with the Objective-C template. See issue [Flutter#16049](https://github.com/flutter/flutter/issues/16049) for help on integration.
@@ -45,6 +45,16 @@ import 'package:permission_handler/permission_handler.dart';
 PermissionStatus permission = await PermissionHandler().checkPermissionStatus(PermissionGroup.contacts);
 PermissionStatus permission = await PermissionHandler().checkPermissionStatus(PermissionGroup.contacts);
 ```
 ```
 
 
+### Checking service status
+
+``` dart
+import 'package:permission_handler/permission_handler.dart';
+
+ServiceStatus serviceStatus = await PermissionHandler().checkServiceStatus(PermissionGroup.location);
+```
+
+Checking the service status only makes sense for the `PermissionGroup.location` on Android and the `PermissionGroup.location`, `PermissionGroup.locationWhenInUser`, `PermissionGroup.locationAlways` or `PermissionGroup.sensors` on iOS. All other permission groups are not backed by a separate service and will always return `ServiceStatus.notApplicable`.
+
 ### Open app settings
 ### Open app settings
 
 
 ``` dart
 ``` dart

android/src/main/kotlin/com/baseflow/permissionhandler/PermissionHandlerPlugin.kt

@@ -12,6 +12,7 @@ import androidx.core.content.ContextCompat
 import android.util.Log
 import android.util.Log
 import com.baseflow.permissionhandler.data.PermissionGroup
 import com.baseflow.permissionhandler.data.PermissionGroup
 import com.baseflow.permissionhandler.data.PermissionStatus
 import com.baseflow.permissionhandler.data.PermissionStatus
+import com.baseflow.permissionhandler.data.ServiceStatus
 import com.baseflow.permissionhandler.utils.Codec
 import com.baseflow.permissionhandler.utils.Codec
 import io.flutter.plugin.common.MethodChannel
 import io.flutter.plugin.common.MethodChannel
 import io.flutter.plugin.common.MethodChannel.MethodCallHandler
 import io.flutter.plugin.common.MethodChannel.MethodCallHandler
@@ -99,7 +100,14 @@ class PermissionHandlerPlugin(private val registrar: Registrar, private var requ
             call.method == "checkPermissionStatus" -> {
             call.method == "checkPermissionStatus" -> {
                 val permission = Codec.decodePermissionGroup(call.arguments)
                 val permission = Codec.decodePermissionGroup(call.arguments)
                 val permissionStatus = checkPermissionStatus(permission)
                 val permissionStatus = checkPermissionStatus(permission)
-                handleSuccess(permissionStatus, result)
+
+                result?.success(Codec.encodePermissionStatus(permissionStatus))
+            }
+            call.method == "checkServiceStatus" -> {
+                val permission = Codec.decodePermissionGroup(call.arguments)
+                val serviceStatus = checkServiceStatus(permission)
+
+                result?.success(Codec.encodeServiceStatus(serviceStatus))
             }
             }
             call.method == "requestPermissions" -> {
             call.method == "requestPermissions" -> {
                 if (mResult != null) {
                 if (mResult != null) {
@@ -168,6 +176,20 @@ class PermissionHandlerPlugin(private val registrar: Registrar, private var requ
         return PermissionStatus.GRANTED
         return PermissionStatus.GRANTED
     }
     }
 
 
+    private fun checkServiceStatus(permission: PermissionGroup) : ServiceStatus {
+        val context: Context? = registrar.activity() ?: registrar.activeContext()
+        if (context == null) {
+            Log.d(mLogTag, "Unable to detect current Activity or App Context.")
+            return ServiceStatus.UNKNOWN
+        }
+
+        if (permission == PermissionGroup.LOCATION || permission == PermissionGroup.LOCATION_ALWAYS || permission == PermissionGroup.LOCATION_WHEN_IN_USE) {
+            return if(isLocationServiceEnabled(context)) ServiceStatus.ENABLED else ServiceStatus.DISABLED
+        }
+
+        return ServiceStatus.NOT_APPLICABLE
+    }
+
     private fun shouldShowRequestPermissionRationale(permission: PermissionGroup) : Boolean {
     private fun shouldShowRequestPermissionRationale(permission: PermissionGroup) : Boolean {
         val activity = registrar.activity()
         val activity = registrar.activity()
         if(activity == null)
         if(activity == null)
@@ -479,8 +501,4 @@ class PermissionHandlerPlugin(private val registrar: Registrar, private var requ
             return !TextUtils.isEmpty(locationProviders)
             return !TextUtils.isEmpty(locationProviders)
         }
         }
     }
     }
-
-    private fun handleSuccess(permissionStatus: PermissionStatus, result: Result?) {
-        result?.success(Codec.encodePermissionStatus(permissionStatus))
-    }
 }
 }

android/src/main/kotlin/com/baseflow/permissionhandler/data/ServiceStatus.kt

+package com.baseflow.permissionhandler.data
+
+import com.google.gson.annotations.SerializedName
+
+enum class ServiceStatus {
+    @SerializedName("unknown")
+    UNKNOWN,
+    @SerializedName("disabled")
+    DISABLED,
+    @SerializedName("enabled")
+    ENABLED,
+    @SerializedName("notApplicable")
+    NOT_APPLICABLE,
+}
\ No newline at end of file

android/src/main/kotlin/com/baseflow/permissionhandler/utils/Codec.kt

@@ -2,6 +2,7 @@ package com.baseflow.permissionhandler.utils
 
 
 import com.baseflow.permissionhandler.data.PermissionGroup
 import com.baseflow.permissionhandler.data.PermissionGroup
 import com.baseflow.permissionhandler.data.PermissionStatus
 import com.baseflow.permissionhandler.data.PermissionStatus
+import com.baseflow.permissionhandler.data.ServiceStatus
 import com.google.gson.Gson
 import com.google.gson.Gson
 import com.google.gson.GsonBuilder
 import com.google.gson.GsonBuilder
 import com.google.gson.reflect.TypeToken
 import com.google.gson.reflect.TypeToken
@@ -29,6 +30,11 @@ class Codec {
         }
         }
 
 
         @JvmStatic
         @JvmStatic
+        fun encodeServiceStatus(serviceStatus: ServiceStatus) : String {
+            return gsonDecoder.toJson(serviceStatus)
+        }
+
+        @JvmStatic
         fun encodePermissionRequestResult(permissionResults: Map<PermissionGroup, PermissionStatus>) : String {
         fun encodePermissionRequestResult(permissionResults: Map<PermissionGroup, PermissionStatus>) : String {
             val jsonString = gsonDecoder.toJson(permissionResults)
             val jsonString = gsonDecoder.toJson(permissionResults)
             return jsonString
             return jsonString

example/lib/main.dart

@@ -98,12 +98,27 @@ class _PermissionState extends State<PermissionWidget> {
         _permissionStatus.toString(),
         _permissionStatus.toString(),
         style: TextStyle(color: getPermissionColor()),
         style: TextStyle(color: getPermissionColor()),
       ),
       ),
-      onTap: () async {
+      trailing: IconButton(
+          icon: const Icon(Icons.info),
+          onPressed: () {
+            checkServiceStatus(context, _permissionGroup);
+          }),
+      onTap: () {
         requestPermission(_permissionGroup);
         requestPermission(_permissionGroup);
       },
       },
     );
     );
   }
   }
 
 
+  void checkServiceStatus(BuildContext context, PermissionGroup permission) {
+    PermissionHandler().checkServiceStatus(permission)
+        .then((ServiceStatus serviceStatus) {
+          final SnackBar snackBar = SnackBar(
+              content: Text(serviceStatus.toString()));
+
+          Scaffold.of(context).showSnackBar(snackBar);
+        });
+  }
+
   void requestPermission(PermissionGroup permission) {
   void requestPermission(PermissionGroup permission) {
     final List<PermissionGroup> permissions = <PermissionGroup>[permission];
     final List<PermissionGroup> permissions = <PermissionGroup>[permission];
     final Future<Map<PermissionGroup, PermissionStatus>> requestFuture =
     final Future<Map<PermissionGroup, PermissionStatus>> requestFuture =

ios/Classes/PermissionManager.swift

@@ -22,6 +22,13 @@ class PermissionManager: NSObject {
         result(Codec.encodePermissionStatus(permissionStatus: permissionStatus))
         result(Codec.encodePermissionStatus(permissionStatus: permissionStatus))
     }
     }
     
     
+    static func checkServiceStatus(permission: PermissionGroup, result: @escaping FlutterResult) {
+        let permissionStrategy = PermissionManager.createPermissionStrategy(permission: permission)
+        let serviceStatus = permissionStrategy.checkServiceStatus(permission: permission)
+        
+        result(Codec.encodeServiceStatus(serviceStatus: serviceStatus))
+    }
+    
     func requestPermissions(permissions: [PermissionGroup], completion: @escaping PermissionRequestCompletion) {
     func requestPermissions(permissions: [PermissionGroup], completion: @escaping PermissionRequestCompletion) {
         var requestQueue = Set(permissions.map { $0 })
         var requestQueue = Set(permissions.map { $0 })
         var permissionStatusResult: [PermissionGroup: PermissionStatus] = [:]
         var permissionStatusResult: [PermissionGroup: PermissionStatus] = [:]

ios/Classes/SwiftPermissionHandlerPlugin.swift

@@ -25,6 +25,12 @@ public class SwiftPermissionHandlerPlugin: NSObject, FlutterPlugin {
             PermissionManager.checkPermissionStatus(
             PermissionManager.checkPermissionStatus(
                 permission: permission,
                 permission: permission,
                 result: result)
                 result: result)
+        } else if call.method == "checkServiceStatus" {
+            let permission: PermissionGroup = Codec.decodePermissionGroup(from: call.arguments)
+            
+            PermissionManager.checkServiceStatus(
+                permission: permission,
+                result: result)
         } else if call.method == "requestPermissions" {
         } else if call.method == "requestPermissions" {
             if _methodResult != nil {
             if _methodResult != nil {
                 result(FlutterError(
                 result(FlutterError(

ios/Classes/data/ServiceStatus.swift

+//
+//  ServiceStatus.swift
+//  permission_handler
+//
+//  Created by Maurits van Beusekom on 12/02/2019.
+//
+
+import Foundation
+
+enum ServiceStatus : String, Codable {
+    case disabled = "disabled"
+    case enabled = "enabled"
+    case notApplicable = "notApplicable"
+    case unknown = "unknown"
+}

ios/Classes/strategies/AudioVideoPermissionStrategy.swift

@@ -19,6 +19,10 @@ class AudioVideoPermissionStrategy : NSObject, PermissionStrategy {
         return PermissionStatus.unknown
         return PermissionStatus.unknown
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return ServiceStatus.notApplicable
+    }
+    
     private static func getPermissionStatus(mediaType: AVMediaType) -> PermissionStatus {
     private static func getPermissionStatus(mediaType: AVMediaType) -> PermissionStatus {
         let status: AVAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: mediaType)
         let status: AVAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: mediaType)
         
         

ios/Classes/strategies/ContactPermissionStrategy.swift

@@ -45,6 +45,10 @@ class ContactPermissionStrategy : NSObject, PermissionStrategy {
         }
         }
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return ServiceStatus.notApplicable
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
         let permissionStatus = checkPermissionStatus(permission: permission)
         let permissionStatus = checkPermissionStatus(permission: permission)
         
         

ios/Classes/strategies/EventPermissionStrategy.swift

@@ -36,6 +36,10 @@ class EventPermissionStrategy : NSObject, PermissionStrategy {
         }
         }
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return ServiceStatus.notApplicable
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
         let permissionStatus = checkPermissionStatus(permission: permission)
         let permissionStatus = checkPermissionStatus(permission: permission)
         
         

ios/Classes/strategies/LocationPermissionStrategy.swift

@@ -23,13 +23,19 @@ class LocationPermissionStrategy : NSObject, PermissionStrategy, CLLocationManag
             permission: permission,
             permission: permission,
             authorizationStatus: authorizationStatus)
             authorizationStatus: authorizationStatus)
         
         
-        if permissionStatus == PermissionStatus.granted && !CLLocationManager.locationServicesEnabled() {
+        if (permissionStatus == PermissionStatus.granted || permissionStatus == PermissionStatus.denied) && !CLLocationManager.locationServicesEnabled() {
             return PermissionStatus.disabled
             return PermissionStatus.disabled
         }
         }
         
         
         return permissionStatus
         return permissionStatus
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return CLLocationManager.locationServicesEnabled()
+            ? ServiceStatus.enabled
+            : ServiceStatus.disabled
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
         let permissionStatus = checkPermissionStatus(permission: permission)
         let permissionStatus = checkPermissionStatus(permission: permission)
         
         

ios/Classes/strategies/MediaLibraryPermissionStrategy.swift

@@ -24,6 +24,10 @@ class MediaLibraryPermissionStrategy : NSObject, PermissionStrategy {
         return PermissionStatus.unknown
         return PermissionStatus.unknown
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return ServiceStatus.notApplicable
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) -> Void {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) -> Void {
         let status = checkPermissionStatus(permission: permission)
         let status = checkPermissionStatus(permission: permission)
         if status != PermissionStatus.unknown {
         if status != PermissionStatus.unknown {

ios/Classes/strategies/PermissionStrategy.swift

@@ -11,5 +11,6 @@ typealias PermissionStatusHandler = (_ permissionStatus: PermissionStatus) -> Vo
 
 
 protocol PermissionStrategy {
 protocol PermissionStrategy {
     func checkPermissionStatus(permission: PermissionGroup) -> PermissionStatus
     func checkPermissionStatus(permission: PermissionGroup) -> PermissionStatus
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler)
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler)
 }
 }

ios/Classes/strategies/PhotoPermissionStrategy.swift

@@ -20,6 +20,10 @@ class PhotoPermissionStrategy : NSObject, PermissionStrategy {
         return PhotoPermissionStrategy.determinePermissionStatus(authorizationStatus: status)
         return PhotoPermissionStrategy.determinePermissionStatus(authorizationStatus: status)
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return ServiceStatus.notApplicable
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
         let status = checkPermissionStatus(permission: permission)
         let status = checkPermissionStatus(permission: permission)
         
         

ios/Classes/strategies/SensorPermissionStrategy.swift

@@ -30,7 +30,7 @@ class SensorPermissionStrategy : NSObject, PermissionStrategy {
                 permissionStatus = PermissionStatus.unknown
                 permissionStatus = PermissionStatus.unknown
             }
             }
             
             
-            if permissionStatus == PermissionStatus.granted && !CMMotionActivityManager.isActivityAvailable() {
+            if (permissionStatus == PermissionStatus.granted || permissionStatus == PermissionStatus.denied) && !CMMotionActivityManager.isActivityAvailable() {
                 return PermissionStatus.disabled
                 return PermissionStatus.disabled
             } else {
             } else {
                 return permissionStatus
                 return permissionStatus
@@ -40,6 +40,16 @@ class SensorPermissionStrategy : NSObject, PermissionStrategy {
         return PermissionStatus.unknown
         return PermissionStatus.unknown
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        if #available(iOS 11.0, *) {
+            return CMMotionActivityManager.isActivityAvailable()
+                ? ServiceStatus.enabled
+                : ServiceStatus.disabled
+        }
+        
+        return ServiceStatus.unknown
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
         let status = checkPermissionStatus(permission: permission)
         let status = checkPermissionStatus(permission: permission)
         
         

ios/Classes/strategies/SpeechPermissionStrategy.swift

@@ -24,6 +24,10 @@ class SpeechPermissionStrategy : NSObject, PermissionStrategy {
         return PermissionStatus.unknown
         return PermissionStatus.unknown
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return ServiceStatus.notApplicable
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
         let status = checkPermissionStatus(permission: permission)
         let status = checkPermissionStatus(permission: permission)
         
         

ios/Classes/strategies/UnknownPermissionStrategy.swift

@@ -12,6 +12,10 @@ class UnknownPermissionStrategy : NSObject, PermissionStrategy {
         return PermissionStatus.unknown
         return PermissionStatus.unknown
     }
     }
     
     
+    func checkServiceStatus(permission: PermissionGroup) -> ServiceStatus {
+        return ServiceStatus.unknown
+    }
+    
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
     func requestPermission(permission: PermissionGroup, completionHandler: @escaping PermissionStatusHandler) {
         completionHandler(PermissionStatus.unknown)
         completionHandler(PermissionStatus.unknown)
     }
     }

ios/Classes/utils/Codec.swift

@@ -31,6 +31,11 @@ struct Codec {
         return status
         return status
     }
     }
     
     
+    static func encodeServiceStatus(serviceStatus: ServiceStatus) -> String? {
+        let status = "\"" + serviceStatus.rawValue + "\""
+        return status
+    }
+    
     static func encodePermissionRequestResult(permissionStatusResult: [PermissionGroup: PermissionStatus]) -> String? {
     static func encodePermissionRequestResult(permissionStatusResult: [PermissionGroup: PermissionStatus]) -> String? {
         let jsonDict = Dictionary(uniqueKeysWithValues:
         let jsonDict = Dictionary(uniqueKeysWithValues:
             permissionStatusResult.map {
             permissionStatusResult.map {

ios/permission_handler.podspec

@@ -3,7 +3,7 @@
 #
 #
 Pod::Spec.new do |s|
 Pod::Spec.new do |s|
   s.name             = 'permission_handler'
   s.name             = 'permission_handler'
-  s.version          = '2.1.3'
+  s.version          = '2.2.0'
   s.summary          = 'Permission plugin for Flutter.'
   s.summary          = 'Permission plugin for Flutter.'
   s.description      = <<-DESC
   s.description      = <<-DESC
 Permission plugin for Flutter. This plugin provides a cross-platform (iOS, Android) API to request and check permissions.
 Permission plugin for Flutter. This plugin provides a cross-platform (iOS, Android) API to request and check permissions.

lib/permission_enums.dart

@@ -18,6 +18,21 @@ enum PermissionStatus {
   unknown
   unknown
 }
 }
 
 
+/// Defines the state of a service related to the permission group
+enum ServiceStatus {
+  /// The unknown service status indicates the state of the service could not be determined.
+  unknown,
+
+  /// There is not separate service for the supplied permission group.
+  notApplicable,
+
+  /// The service for the supplied permission group is disabled.
+  disabled,
+
+  /// The service for the supplied permission group is enabled.
+  enabled
+}
+
 /// Defines the permission groups for which permissions can be checked or requested.
 /// Defines the permission groups for which permissions can be checked or requested.
 enum PermissionGroup {
 enum PermissionGroup {
   /// The unknown permission only used for return type, never requested
   /// The unknown permission only used for return type, never requested

lib/permission_handler.dart

@@ -29,20 +29,35 @@ class PermissionHandler {
 
 
   final MethodChannel _methodChannel;
   final MethodChannel _methodChannel;
 
 
+  /// Check current permission status.
+  ///
   /// Returns a [Future] containing the current permission status for the supplied [PermissionGroup].
   /// Returns a [Future] containing the current permission status for the supplied [PermissionGroup].
   Future<PermissionStatus> checkPermissionStatus(
   Future<PermissionStatus> checkPermissionStatus(
       PermissionGroup permission) async {
       PermissionGroup permission) async {
-    final String status = await _methodChannel.invokeMethod(
+    final String status = await _methodChannel.invokeMethod<String>(
         'checkPermissionStatus', Codec.encodePermissionGroup(permission));
         'checkPermissionStatus', Codec.encodePermissionGroup(permission));
 
 
     return Codec.decodePermissionStatus(status);
     return Codec.decodePermissionStatus(status);
   }
   }
 
 
+  /// Check current service status.
+  ///
+  /// Returns a [Future] containing the current service status for the supplied [PermissionGroup].
+  Future<ServiceStatus> checkServiceStatus(
+      PermissionGroup permission) async {
+    final String status = await _methodChannel.invokeMethod<String>(
+      'checkServiceStatus', Codec.encodePermissionGroup(permission));
+
+    return Codec.decodeServiceStatus(status);
+  }
+
   /// Open the App settings page.
   /// Open the App settings page.
   ///
   ///
   /// Returns [true] if the app settings page could be opened, otherwise [false] is returned.
   /// Returns [true] if the app settings page could be opened, otherwise [false] is returned.
   Future<bool> openAppSettings() async {
   Future<bool> openAppSettings() async {
-    final bool hasOpened = await _methodChannel.invokeMethod('openAppSettings');
+    final bool hasOpened = await _methodChannel.invokeMethod<bool>(
+        'openAppSettings');
+
     return hasOpened;
     return hasOpened;
   }
   }
 
 
@@ -53,7 +68,8 @@ class PermissionHandler {
       List<PermissionGroup> permissions) async {
       List<PermissionGroup> permissions) async {
     final String jsonData = Codec.encodePermissionGroups(permissions);
     final String jsonData = Codec.encodePermissionGroups(permissions);
     final String status =
     final String status =
-        await _methodChannel.invokeMethod('requestPermissions', jsonData);
+        await _methodChannel.invokeMethod<String>(
+            'requestPermissions', jsonData);
 
 
     return Codec.decodePermissionRequestResult(status);
     return Codec.decodePermissionRequestResult(status);
   }
   }
@@ -68,7 +84,7 @@ class PermissionHandler {
       return false;
       return false;
     }
     }
 
 
-    final bool shouldShowRationale = await _methodChannel.invokeMethod(
+    final bool shouldShowRationale = await _methodChannel.invokeMethod<bool>(
         'shouldShowRequestPermissionRationale',
         'shouldShowRequestPermissionRationale',
         Codec.encodePermissionGroup(permission));
         Codec.encodePermissionGroup(permission));
 
 

lib/utils/codec.dart

@@ -2,12 +2,19 @@ part of permission_handler;
 
 
 class Codec {
 class Codec {
   static PermissionStatus decodePermissionStatus(String value) {
   static PermissionStatus decodePermissionStatus(String value) {
-    final dynamic permission = json.decode(value);
+    final String permission = json.decode(value);
 
 
     return PermissionStatus.values.firstWhere(
     return PermissionStatus.values.firstWhere(
         (PermissionStatus e) => e.toString().split('.').last == permission);
         (PermissionStatus e) => e.toString().split('.').last == permission);
   }
   }
 
 
+  static ServiceStatus decodeServiceStatus(String value) {
+    final String status = json.decode(value);
+
+    return ServiceStatus.values.firstWhere(
+        (ServiceStatus s) => s.toString().split('.').last == status);
+  }
+
   static Map<PermissionGroup, PermissionStatus> decodePermissionRequestResult(
   static Map<PermissionGroup, PermissionStatus> decodePermissionRequestResult(
       String value) {
       String value) {
     final Map<String, dynamic> jsonObject = json.decode(value);
     final Map<String, dynamic> jsonObject = json.decode(value);

pubspec.yaml

 name: permission_handler
 name: permission_handler
 description: Permission plugin for Flutter. This plugin provides a cross-platform (iOS, Android) API to request and check permissions.
 description: Permission plugin for Flutter. This plugin provides a cross-platform (iOS, Android) API to request and check permissions.
-version: 2.1.3
+version: 2.2.0
 author: Baseflow <hello@baseflow.com>
 author: Baseflow <hello@baseflow.com>
 homepage: https://github.com/baseflowit/flutter-permission-handler
 homepage: https://github.com/baseflowit/flutter-permission-handler