[google_map_flutter] Add style to widget - platform impls (flutter#6205)

Platform implementations portion of flutter#6192

Adds handling of `MapConfiguration.style` and implements new `getStyleError` method.

Part of flutter/flutter#66207

packages/google_maps_flutter/google_maps_flutter_android/CHANGELOG.md

@@ -1,5 +1,7 @@
-## NEXT
+## 2.7.0
 
+* Adds support for `MapConfiguration.style`.
+* Adds support for `getStyleError`.
 * Updates minimum supported SDK version to Flutter 3.13/Dart 3.1.
 * Updates compileSdk version to 34.
 

packages/google_maps_flutter/google_maps_flutter_android/android/src/main/java/io/flutter/plugins/googlemaps/Convert.java

@@ -377,6 +377,10 @@ static void interpretGoogleMapOptions(Object o, GoogleMapOptionsSink sink) {
     if (buildingsEnabled != null) {
       sink.setBuildingsEnabled(toBoolean(buildingsEnabled));
     }
+    final Object style = data.get("style");
+    if (style != null) {
+      sink.setMapStyle(toString(style));
+    }
   }
 
   /** Returns the dartMarkerId of the interpreted marker. */

packages/google_maps_flutter/google_maps_flutter_android/android/src/main/java/io/flutter/plugins/googlemaps/GoogleMapBuilder.java

@@ -6,6 +6,7 @@
 
 import android.content.Context;
 import android.graphics.Rect;
+import androidx.annotation.Nullable;
 import com.google.android.gms.maps.GoogleMapOptions;
 import com.google.android.gms.maps.model.CameraPosition;
 import com.google.android.gms.maps.model.LatLngBounds;
@@ -27,6 +28,7 @@ class GoogleMapBuilder implements GoogleMapOptionsSink {
   private Object initialCircles;
   private List<Map<String, ?>> initialTileOverlays;
   private Rect padding = new Rect(0, 0, 0, 0);
+  private @Nullable String style;
 
   GoogleMapController build(
       int id,
@@ -48,6 +50,7 @@ GoogleMapController build(
     controller.setInitialCircles(initialCircles);
     controller.setPadding(padding.top, padding.left, padding.bottom, padding.right);
     controller.setInitialTileOverlays(initialTileOverlays);
+    controller.setMapStyle(style);
     return controller;
   }
 
@@ -178,4 +181,9 @@ public void setInitialCircles(Object initialCircles) {
   public void setInitialTileOverlays(List<Map<String, ?>> initialTileOverlays) {
     this.initialTileOverlays = initialTileOverlays;
   }
+
+  @Override
+  public void setMapStyle(@Nullable String style) {
+    this.style = style;
+  }
 }

packages/google_maps_flutter/google_maps_flutter_android/android/src/main/java/io/flutter/plugins/googlemaps/GoogleMapController.java

@@ -48,6 +48,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 
 /** Controller of a single GoogleMaps MapView instance. */
 final class GoogleMapController
@@ -87,6 +88,9 @@ final class GoogleMapController
   private List<Object> initialPolylines;
   private List<Object> initialCircles;
   private List<Map<String, ?>> initialTileOverlays;
+  // Null except between initialization and onMapReady.
+  private @Nullable String initialMapStyle;
+  private @Nullable String lastStyleError;
   @VisibleForTesting List<Float> initialPadding;
 
   GoogleMapController(
@@ -169,6 +173,10 @@ public void onMapReady(GoogleMap googleMap) {
           initialPadding.get(2),
           initialPadding.get(3));
     }
+    if (initialMapStyle != null) {
+      updateMapStyle(initialMapStyle);
+      initialMapStyle = null;
+    }
   }
 
   // Returns the first TextureView found in the view hierarchy.
@@ -459,26 +467,22 @@ public void onSnapshotReady(Bitmap bitmap) {
         }
       case "map#setStyle":
         {
-          boolean mapStyleSet;
-          if (call.arguments instanceof String) {
-            String mapStyle = (String) call.arguments;
-            if (mapStyle == null) {
-              mapStyleSet = googleMap.setMapStyle(null);
-            } else {
-              mapStyleSet = googleMap.setMapStyle(new MapStyleOptions(mapStyle));
-            }
-          } else {
-            mapStyleSet = googleMap.setMapStyle(null);
-          }
+          Object arg = call.arguments;
+          final String style = arg instanceof String ? (String) arg : null;
+          final boolean mapStyleSet = updateMapStyle(style);
           ArrayList<Object> mapStyleResult = new ArrayList<>(2);
           mapStyleResult.add(mapStyleSet);
           if (!mapStyleSet) {
-            mapStyleResult.add(
-                "Unable to set the map style. Please check console logs for errors.");
+            mapStyleResult.add(lastStyleError);
           }
           result.success(mapStyleResult);
           break;
         }
+      case "map#getStyleError":
+        {
+          result.success(lastStyleError);
+          break;
+        }
       case "tileOverlays#update":
         {
           List<Map<String, ?>> tileOverlaysToAdd = call.argument("tileOverlaysToAdd");
@@ -926,4 +930,22 @@ public void setTrafficEnabled(boolean trafficEnabled) {
   public void setBuildingsEnabled(boolean buildingsEnabled) {
     this.buildingsEnabled = buildingsEnabled;
   }
+
+  public void setMapStyle(@Nullable String style) {
+    if (googleMap == null) {
+      initialMapStyle = style;
+    } else {
+      updateMapStyle(style);
+    }
+  }
+
+  private boolean updateMapStyle(String style) {
+    // Dart passes an empty string to indicate that the style should be cleared.
+    final MapStyleOptions mapStyleOptions =
+        style == null || style.isEmpty() ? null : new MapStyleOptions(style);
+    final boolean set = Objects.requireNonNull(googleMap).setMapStyle(mapStyleOptions);
+    lastStyleError =
+        set ? null : "Unable to set the map style. Please check console logs for errors.";
+    return set;
+  }
 }

packages/google_maps_flutter/google_maps_flutter_android/android/src/main/java/io/flutter/plugins/googlemaps/GoogleMapOptionsSink.java

@@ -4,6 +4,7 @@
 
 package io.flutter.plugins.googlemaps;
 
+import androidx.annotation.Nullable;
 import com.google.android.gms.maps.model.LatLngBounds;
 import java.util.List;
 import java.util.Map;
@@ -55,4 +56,6 @@ interface GoogleMapOptionsSink {
   void setInitialCircles(Object initialCircles);
 
   void setInitialTileOverlays(List<Map<String, ?>> initialTileOverlays);
+
+  void setMapStyle(@Nullable String style);
 }

packages/google_maps_flutter/google_maps_flutter_android/example/integration_test/google_maps_tests.dart

@@ -722,7 +722,8 @@ void googleMapsTests() {
         await controllerCompleter.future;
     const String mapStyle =
         '[{"elementType":"geometry","stylers":[{"color":"#242f3e"}]}]';
-    await controller.setMapStyle(mapStyle);
+    await GoogleMapsFlutterPlatform.instance
+        .setMapStyle(mapStyle, mapId: controller.mapId);
   });
 
   testWidgets('testSetMapStyle invalid Json String',
@@ -746,10 +747,12 @@ void googleMapsTests() {
         await controllerCompleter.future;
 
     try {
-      await controller.setMapStyle('invalid_value');
+      await GoogleMapsFlutterPlatform.instance
+          .setMapStyle('invalid_value', mapId: controller.mapId);
       fail('expected MapStyleException');
     } on MapStyleException catch (e) {
       expect(e.cause, isNotNull);
+      expect(await controller.getStyleError(), isNotNull);
     }
   });
 
@@ -771,7 +774,8 @@ void googleMapsTests() {
 
     final ExampleGoogleMapController controller =
         await controllerCompleter.future;
-    await controller.setMapStyle(null);
+    await GoogleMapsFlutterPlatform.instance
+        .setMapStyle(null, mapId: controller.mapId);
   });
 
   testWidgets('testGetLatLng', (WidgetTester tester) async {
@@ -1211,6 +1215,58 @@ void googleMapsTests() {
       await mapIdCompleter.future;
     },
   );
+
+  testWidgets('getStyleError reports last error', (WidgetTester tester) async {
+    final Key key = GlobalKey();
+    final Completer<ExampleGoogleMapController> controllerCompleter =
+        Completer<ExampleGoogleMapController>();
+
+    await tester.pumpWidget(Directionality(
+      textDirection: TextDirection.ltr,
+      child: ExampleGoogleMap(
+        key: key,
+        initialCameraPosition: _kInitialCameraPosition,
+        style: '[[[this is an invalid style',
+        onMapCreated: (ExampleGoogleMapController controller) {
+          controllerCompleter.complete(controller);
+        },
+      ),
+    ));
+
+    final ExampleGoogleMapController controller =
+        await controllerCompleter.future;
+    String? error = await controller.getStyleError();
+    for (int i = 0; i < 1000 && error == null; i++) {
+      await Future<void>.delayed(const Duration(milliseconds: 10));
+      error = await controller.getStyleError();
+    }
+    expect(error, isNotNull);
+  });
+
+  testWidgets('getStyleError returns null for a valid style',
+      (WidgetTester tester) async {
+    final Key key = GlobalKey();
+    final Completer<ExampleGoogleMapController> controllerCompleter =
+        Completer<ExampleGoogleMapController>();
+
+    await tester.pumpWidget(Directionality(
+      textDirection: TextDirection.ltr,
+      child: ExampleGoogleMap(
+        key: key,
+        initialCameraPosition: _kInitialCameraPosition,
+        // An empty array is the simplest valid style.
+        style: '[]',
+        onMapCreated: (ExampleGoogleMapController controller) {
+          controllerCompleter.complete(controller);
+        },
+      ),
+    ));
+
+    final ExampleGoogleMapController controller =
+        await controllerCompleter.future;
+    final String? error = await controller.getStyleError();
+    expect(error, isNull);
+  });
 }
 
 class _DebugTileProvider implements TileProvider {

packages/google_maps_flutter/google_maps_flutter_android/example/lib/example_google_map.dart

@@ -144,12 +144,6 @@ class ExampleGoogleMapController {
         .moveCamera(cameraUpdate, mapId: mapId);
   }
 
-  /// Sets the styling of the base map.
-  Future<void> setMapStyle(String? mapStyle) {
-    return GoogleMapsFlutterPlatform.instance
-        .setMapStyle(mapStyle, mapId: mapId);
-  }
-
   /// Return [LatLngBounds] defining the region that is visible in a map.
   Future<LatLngBounds> getVisibleRegion() {
     return GoogleMapsFlutterPlatform.instance.getVisibleRegion(mapId: mapId);
@@ -195,6 +189,11 @@ class ExampleGoogleMapController {
     return GoogleMapsFlutterPlatform.instance.takeSnapshot(mapId: mapId);
   }
 
+  /// Returns the last style error, if any.
+  Future<String?> getStyleError() {
+    return GoogleMapsFlutterPlatform.instance.getStyleError(mapId: mapId);
+  }
+
   /// Disposes of the platform resources
   void dispose() {
     GoogleMapsFlutterPlatform.instance.dispose(mapId: mapId);
@@ -245,6 +244,7 @@ class ExampleGoogleMap extends StatefulWidget {
     this.onTap,
     this.onLongPress,
     this.cloudMapId,
+    this.style,
   });
 
   /// Callback method for when the map is ready to be used.
@@ -353,6 +353,9 @@ class ExampleGoogleMap extends StatefulWidget {
   /// for more details.
   final String? cloudMapId;
 
+  /// The locally configured style for the map.
+  final String? style;
+
   /// Creates a [State] for this [ExampleGoogleMap].
   @override
   State createState() => _ExampleGoogleMapState();
@@ -539,5 +542,6 @@ MapConfiguration _configurationFromMapWidget(ExampleGoogleMap map) {
     trafficEnabled: map.trafficEnabled,
     buildingsEnabled: map.buildingsEnabled,
     cloudMapId: map.cloudMapId,
+    style: map.style,
   );
 }

packages/google_maps_flutter/google_maps_flutter_android/example/lib/map_ui.dart

@@ -60,6 +60,7 @@ class MapUiBodyState extends State<MapUiBody> {
   bool _myLocationButtonEnabled = true;
   late ExampleGoogleMapController _controller;
   bool _nightMode = false;
+  String _mapStyle = '';
 
   @override
   void initState() {
@@ -244,27 +245,16 @@ class MapUiBodyState extends State<MapUiBody> {
     return rootBundle.loadString(path);
   }
 
-  void _setMapStyle(String mapStyle) {
-    setState(() {
-      _nightMode = true;
-      _controller.setMapStyle(mapStyle);
-    });
-  }
-
-  // Should only be called if _isMapCreated is true.
   Widget _nightModeToggler() {
-    assert(_isMapCreated);
     return TextButton(
       child: Text('${_nightMode ? 'disable' : 'enable'} night mode'),
-      onPressed: () {
-        if (_nightMode) {
-          setState(() {
-            _nightMode = false;
-            _controller.setMapStyle(null);
-          });
-        } else {
-          _getFileData('assets/night_mode.json').then(_setMapStyle);
-        }
+      onPressed: () async {
+        _nightMode = !_nightMode;
+        final String style =
+            _nightMode ? await _getFileData('assets/night_mode.json') : '';
+        setState(() {
+          _mapStyle = style;
+        });
       },
     );
   }
@@ -279,6 +269,7 @@ class MapUiBodyState extends State<MapUiBody> {
       cameraTargetBounds: _cameraTargetBounds,
       minMaxZoomPreference: _minMaxZoomPreference,
       mapType: _mapType,
+      style: _mapStyle,
       rotateGesturesEnabled: _rotateGesturesEnabled,
       scrollGesturesEnabled: _scrollGesturesEnabled,
       tiltGesturesEnabled: _tiltGesturesEnabled,
@@ -353,5 +344,11 @@ class MapUiBodyState extends State<MapUiBody> {
       _controller = controller;
       _isMapCreated = true;
     });
+    // Log any style errors to the console for debugging.
+    _controller.getStyleError().then((String? error) {
+      if (error != null) {
+        debugPrint(error);
+      }
+    });
   }
 }

packages/google_maps_flutter/google_maps_flutter_android/example/pubspec.yaml

@@ -18,7 +18,7 @@ dependencies:
     # The example app is bundled with the plugin so we use a path dependency on
     # the parent directory to use the current plugin's version.
     path: ../
-  google_maps_flutter_platform_interface: ^2.4.0
+  google_maps_flutter_platform_interface: ^2.5.0
 
 dev_dependencies:
   build_runner: ^2.1.10

packages/google_maps_flutter/google_maps_flutter_android/lib/src/google_maps_flutter_android.dart

@@ -484,6 +484,11 @@ class GoogleMapsFlutterAndroid extends GoogleMapsFlutterPlatform {
     return _channel(mapId).invokeMethod<Uint8List>('map#takeSnapshot');
   }
 
+  @override
+  Future<String?> getStyleError({required int mapId}) {
+    return _channel(mapId).invokeMethod<String>('map#getStyleError');
+  }
+
   /// Set [GoogleMapsFlutterPlatform] to use [AndroidViewSurface] to build the
   /// Google Maps widget.
   ///
@@ -727,6 +732,7 @@ Map<String, Object> _jsonForMapConfiguration(MapConfiguration config) {
     if (config.buildingsEnabled != null)
       'buildingsEnabled': config.buildingsEnabled!,
     if (config.cloudMapId != null) 'cloudMapId': config.cloudMapId!,
+    if (config.style != null) 'style': config.style!,
   };
 }