feat: update geojson data (#39)

android/src/main/kotlin/com/github/josxha/maplibre/MapLibreMapController.kt

@@ -437,6 +437,20 @@ class MapLibreMapController(
         callback(Result.success(Unit))
     }
 
+    override fun updateGeoJsonSource(
+        id: String,
+        data: String,
+        callback: (Result<Unit>) -> Unit
+    ) {
+        val source = mapLibreMap.style?.getSourceAs<GeoJsonSource>(id)
+        if (source == null) {
+            callback(Result.failure(Exception("LAYER_NOT_FOUND")))
+            return
+        }
+        source.setGeoJson(data)
+        callback(Result.success(Unit))
+    }
+
     override fun addImageSource(
         id: String,
         url: String,

android/src/main/kotlin/com/github/josxha/maplibre/Pigeon.g.kt

@@ -388,6 +388,8 @@ interface MapLibreHostApi {
   fun removeImage(id: String, callback: (Result<Unit>) -> Unit)
   /** Add a GeoJSON source to the map style. */
   fun addGeoJsonSource(id: String, data: String, callback: (Result<Unit>) -> Unit)
+  /** Update the data of a GeoJSON source. */
+  fun updateGeoJsonSource(id: String, data: String, callback: (Result<Unit>) -> Unit)
   /** Add a image source to the map style. */
   fun addImageSource(id: String, url: String, coordinates: List<LngLat>, callback: (Result<Unit>) -> Unit)
   /** Add a raster source to the map style. */
@@ -859,6 +861,26 @@ interface MapLibreHostApi {
           channel.setMessageHandler(null)
         }
       }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.maplibre.MapLibreHostApi.updateGeoJsonSource$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val idArg = args[0] as String
+            val dataArg = args[1] as String
+            api.updateGeoJsonSource(idArg, dataArg) { result: Result<Unit> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(wrapError(error))
+              } else {
+                reply.reply(wrapResult(null))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
       run {
         val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.maplibre.MapLibreHostApi.addImageSource$separatedMessageChannelSuffix", codec)
         if (api != null) {

example/lib/animation_page.dart

@@ -0,0 +1,87 @@
+import 'dart:async';
+import 'dart:convert';
+
+import 'package:flutter/material.dart';
+import 'package:http/http.dart';
+import 'package:maplibre/maplibre.dart';
+
+@immutable
+class AnimationPage extends StatefulWidget {
+  const AnimationPage({super.key});
+
+  static const location = '/animation';
+
+  @override
+  State<AnimationPage> createState() => _AnimationPageState();
+}
+
+const _sourceId = 'AnimatedPath';
+
+class _AnimationPageState extends State<AnimationPage> {
+  late final MapController _controller;
+  Timer? _timer;
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: const Text('Animation')),
+      body: MapLibreMap(
+        options: MapOptions(zoom: 14, center: Position(-122.01971, 45.632472)),
+        onMapCreated: (controller) => _controller = controller,
+        onStyleLoaded: _onStyleLoaded,
+      ),
+    );
+  }
+
+  Future<void> _onStyleLoaded() async {
+    final response = await get(
+      Uri.parse('https://maplibre.org/maplibre-gl-js/docs/assets/hike.geojson'),
+    );
+    final geojsonLine = response.body;
+    final geojson = FeatureCollection.fromJson(
+      jsonDecode(geojsonLine) as Map<String, Object?>,
+    );
+    final lineString = geojson.features.first.geometry! as LineString;
+    // TODO: setting the id is currently required as geotypes would set it to null, Feature.id documented at https://datatracker.ietf.org/doc/html/rfc7946#section-3.2
+    geojson.features.first.id = 1;
+    final allCoords = lineString.coordinates;
+
+    // a LineString on MapLibre Native must have at least 2 Points
+    lineString.coordinates = allCoords.sublist(0, 2);
+    await _controller.addSource(
+      GeoJsonSource(id: _sourceId, data: jsonEncode(geojson.toJson())),
+    );
+    await _controller.addLayer(
+      const LineLayer(
+        id: 'geojson-line',
+        sourceId: _sourceId,
+        paint: {'line-color': '#F00', 'line-width': 3},
+      ),
+    );
+
+    var index = 1;
+    _timer = Timer.periodic(const Duration(milliseconds: 1), (timer) {
+      index++;
+      if (index > allCoords.length - 1) {
+        debugPrint('line animation completed');
+        timer.cancel();
+        return;
+      }
+      lineString.coordinates = allCoords.sublist(0, index);
+      _controller.updateGeoJsonSource(
+        id: _sourceId,
+        data: jsonEncode(geojson.toJson()),
+      );
+      debugPrint(
+        '[$index] update line: '
+        '${allCoords[index].lng}, ${allCoords[index].lat}',
+      );
+    });
+  }
+
+  @override
+  void dispose() {
+    _timer?.cancel();
+    super.dispose();
+  }
+}

example/lib/layers_fill_page.dart

@@ -42,6 +42,3 @@ class _LayersFillPageState extends State<LayersFillPage> {
     );
   }
 }
-
-// TODO fill extrusion layer
-// TODO line layer

example/lib/layers_line_page.dart

@@ -41,6 +41,3 @@ class _LayersLinePageState extends State<LayersLinePage> {
     );
   }
 }
-
-// TODO fill extrusion layer
-// TODO line layer

example/lib/main.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:maplibre_example/animation_page.dart';
 import 'package:maplibre_example/annotations_page.dart';
 import 'package:maplibre_example/controller_page.dart';
 import 'package:maplibre_example/events_page.dart';
@@ -33,6 +34,7 @@ class MyApp extends StatelessWidget {
       routes: {
         MenuPage.location: (context) => const MenuPage(),
         KioskPage.location: (context) => const KioskPage(),
+        AnimationPage.location: (context) => const AnimationPage(),
         EventsPage.location: (context) => const EventsPage(),
         StyledMapPage.location: (context) => const StyledMapPage(),
         LayersSymbolPage.location: (context) => const LayersSymbolPage(),

example/lib/menu_page.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
+import 'package:maplibre_example/animation_page.dart';
 import 'package:maplibre_example/annotations_page.dart';
 import 'package:maplibre_example/controller_page.dart';
 import 'package:maplibre_example/events_page.dart';
@@ -68,6 +69,11 @@ class MenuPage extends StatelessWidget {
                 iconData: Icons.looks_two,
                 location: TwoMapsPage.location,
               ),
+              ItemCard(
+                label: 'Animation',
+                iconData: Icons.animation,
+                location: AnimationPage.location,
+              ),
             ],
           ),
           const SliverToBoxAdapter(child: SectionTitle('Map Layers')),

ios/Classes/Pigeon.g.swift

@@ -415,6 +415,8 @@ protocol MapLibreHostApi {
   func removeImage(id: String, completion: @escaping (Result<Void, Error>) -> Void)
   /// Add a GeoJSON source to the map style.
   func addGeoJsonSource(id: String, data: String, completion: @escaping (Result<Void, Error>) -> Void)
+  /// Update the data of a GeoJSON source.
+  func updateGeoJsonSource(id: String, data: String, completion: @escaping (Result<Void, Error>) -> Void)
   /// Add a image source to the map style.
   func addImageSource(id: String, url: String, coordinates: [LngLat], completion: @escaping (Result<Void, Error>) -> Void)
   /// Add a raster source to the map style.
@@ -858,6 +860,25 @@ class MapLibreHostApiSetup {
     } else {
       addGeoJsonSourceChannel.setMessageHandler(nil)
     }
+    /// Update the data of a GeoJSON source.
+    let updateGeoJsonSourceChannel = FlutterBasicMessageChannel(name: "dev.flutter.pigeon.maplibre.MapLibreHostApi.updateGeoJsonSource\(channelSuffix)", binaryMessenger: binaryMessenger, codec: codec)
+    if let api = api {
+      updateGeoJsonSourceChannel.setMessageHandler { message, reply in
+        let args = message as! [Any?]
+        let idArg = args[0] as! String
+        let dataArg = args[1] as! String
+        api.updateGeoJsonSource(id: idArg, data: dataArg) { result in
+          switch result {
+          case .success:
+            reply(wrapResult(nil))
+          case .failure(let error):
+            reply(wrapError(error))
+          }
+        }
+      }
+    } else {
+      updateGeoJsonSourceChannel.setMessageHandler(nil)
+    }
     /// Add a image source to the map style.
     let addImageSourceChannel = FlutterBasicMessageChannel(name: "dev.flutter.pigeon.maplibre.MapLibreHostApi.addImageSource\(channelSuffix)", binaryMessenger: binaryMessenger, codec: codec)
     if let api = api {

lib/src/map_controller.dart

@@ -48,6 +48,9 @@ abstract interface class MapController {
   /// of the layers array and appear visually above all other layers.
   Future<void> addLayer(Layer layer, {String? belowLayerId});
 
+  /// Update the data of a GeoJSON source.
+  Future<void> updateGeoJsonSource({required String id, required String data});
+
   /// Removes the layer with the given ID from the map's style.
   Future<void> removeLayer(String id);
 

lib/src/native/pigeon.g.dart

@@ -968,6 +968,32 @@ class MapLibreHostApi {
     }
   }
 
+  /// Update the data of a GeoJSON source.
+  Future<void> updateGeoJsonSource(
+      {required String id, required String data}) async {
+    final String pigeonVar_channelName =
+        'dev.flutter.pigeon.maplibre.MapLibreHostApi.updateGeoJsonSource$pigeonVar_messageChannelSuffix';
+    final BasicMessageChannel<Object?> pigeonVar_channel =
+        BasicMessageChannel<Object?>(
+      pigeonVar_channelName,
+      pigeonChannelCodec,
+      binaryMessenger: pigeonVar_binaryMessenger,
+    );
+    final List<Object?>? pigeonVar_replyList =
+        await pigeonVar_channel.send(<Object?>[id, data]) as List<Object?>?;
+    if (pigeonVar_replyList == null) {
+      throw _createConnectionError(pigeonVar_channelName);
+    } else if (pigeonVar_replyList.length > 1) {
+      throw PlatformException(
+        code: pigeonVar_replyList[0]! as String,
+        message: pigeonVar_replyList[1] as String?,
+        details: pigeonVar_replyList[2],
+      );
+    } else {
+      return;
+    }
+  }
+
   /// Add a image source to the map style.
   Future<void> addImageSource({
     required String id,

lib/src/native/widget_state.dart

@@ -373,4 +373,11 @@ final class MapLibreMapStateNative extends State<MapLibreMap>
 
   @override
   Future<void> removeImage(String id) => _hostApi.removeImage(id);
+
+  @override
+  Future<void> updateGeoJsonSource({
+    required String id,
+    required String data,
+  }) =>
+      _hostApi.updateGeoJsonSource(id: id, data: data);
 }

lib/src/web/interop/map.dart

@@ -89,6 +89,9 @@ extension type JsMap._(Camera _) implements Camera {
 
   /// Update the maximum bounding box of the map camera.
   external void setMaxBounds(LngLatBounds? maxBounds);
+
+  /// Get a Source by its id.
+  external SourceSpecification getSource(String id);
 }
 
 /// Anonymous MapOptions for the MapLibre JavaScript [JsMap].
@@ -170,6 +173,9 @@ extension type SourceSpecification._(JSObject _) implements JSObject {
     required JSAny urls,
     required JSAny coordinates,
   });
+
+  /// Used to update the data of a GeoJSON source.
+  external void setData(JSAny data);
 }
 
 /// The specifications of map layers.

lib/src/web/widget_state.dart

@@ -527,4 +527,13 @@ final class MapLibreMapStateWeb extends State<MapLibreMap>
 
   @override
   Future<void> removeSource(String id) async => _map.removeSource(id);
+
+  @override
+  Future<void> updateGeoJsonSource({
+    required String id,
+    required String data,
+  }) async {
+    final source = _map.getSource(id);
+    source.setData(parse(data));
+  }
 }