Implemented isPresent on Android package (#204)

* Implemented isPresent on Android

(cherry picked from commit 472c9e7)

* fixed build

geocoding_android/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 3.2.0
+
+  * Exposes isPresent() call that returns true if there is a geocoder implementation present that may return results.
+
 ## 3.1.0
 
   * Fixes deprecation build warnings. 

geocoding_android/android/src/main/java/com/baseflow/geocoding/Geocoding.java

@@ -36,6 +36,15 @@ void setLocaleIdentifier(@Nullable Locale locale) {
         this.locale = locale;
     }
 
+     /**
+     * Returns true if there is a geocoder implementation present that may return results. 
+     * If true, there is still no guarantee that any individual geocoding attempt will succeed.
+     *
+     */
+     boolean isPresent() {
+        return Geocoder.isPresent();
+    }
+
     /**
      * Returns a list of Address objects matching the supplied address string.
      *

geocoding_android/android/src/main/java/com/baseflow/geocoding/MethodCallHandlerImpl.java

@@ -55,6 +55,9 @@ public void onMethodCall(
             case "placemarkFromCoordinates":
                 onPlacemarkFromCoordinates(call, result);
                 break;
+            case "isPresent":
+                onIsPresent(call, result);
+                break;
             default:
                 result.notImplemented();
                 break;
@@ -203,4 +206,9 @@ public void onError(String errorMessage) {
                     }
                 });
     }
+
+    private void onIsPresent(final MethodCall call, final Result result) {
+        boolean isPresent = geocoding.isPresent();
+        result.success(isPresent);
+    }
 }

geocoding_android/example/lib/plugin_example/geocode_page.dart

@@ -154,6 +154,23 @@ class _GeocodeWidgetState extends State<GeocodeWidget> {
                   });
                 }),
           ),
+          const Padding(
+            padding: EdgeInsets.only(top: 8),
+          ),
+          Center(
+            child: ElevatedButton(
+                child: Text('Is present'),
+                onPressed: () {
+                  GeocodingAndroid().isPresent().then((isPresent) {
+                    var output = isPresent
+                        ? "Geocoder is present"
+                        : "Geocoder is not present";
+                    setState(() {
+                      _output = output;
+                    });
+                  });
+                }),
+          ),
           Expanded(
             child: SingleChildScrollView(
               child: Container(

geocoding_android/lib/geocoding_android.dart

@@ -44,6 +44,20 @@ class GeocodingAndroid extends GeocodingPlatform {
     }
   }
 
+  @override
+  Future<bool> isPresent() async {
+    try {
+      final isPresent = await _channel.invokeMethod(
+        'isPresent',
+      );
+
+      return isPresent;
+    } on PlatformException catch (e) {
+      _handlePlatformException(e);
+      rethrow;
+    }
+  }
+
   @override
   Future<List<Placemark>> placemarkFromCoordinates(
     double latitude,

geocoding_android/pubspec.yaml

@@ -1,6 +1,6 @@
 name: geocoding_android
 description: A Flutter Geocoding plugin which provides easy geocoding and reverse-geocoding features.
-version: 3.1.0
+version: 3.2.0
 repository: https://github.com/baseflow/flutter-geocoding/tree/main/geocoding_android
 issue_tracker: https://github.com/Baseflow/flutter-geocoding/issues