Expose CameraChanged/cameraState

CHANGELOG.md

@@ -1,3 +1,15 @@
+### main
+
+* Expose current map's camera state on `CameraChanged` event.
+
+You can now observe the map's camera updates with `onCameraChangeListener`
+
+```dart
+onCameraChangeListener(CameraChangedEventData data) {
+  print("CameraChangedEventData: timestamp: ${data.timestamp}, cameraState: ${data.cameraState}");
+}
+```
+
 ### 2.3.0-rc.1
 
 * Expose API to clear map data, and to set options to `TileStore`.

example/lib/full_map.dart

@@ -36,7 +36,7 @@ class FullMapState extends State<FullMap> {
   }
 
   _onCameraChangeListener(CameraChangedEventData data) {
-    print("CameraChangedEventData: timestamp: ${data.timestamp}");
+    print("CameraChangedEventData: ${data.debugInfo}");
   }
 
   _onResourceRequestListener(ResourceEventData data) {
@@ -142,3 +142,17 @@ class FullMapState extends State<FullMap> {
         ));
   }
 }
+
+extension on CameraChangedEventData {
+
+  String get debugInfo {
+    return "timestamp ${DateTime.fromMicrosecondsSinceEpoch(timestamp)}, camera: ${cameraState.debugInfo}";
+  }
+}
+
+extension on CameraState {
+
+  String get debugInfo {
+    return "lat: ${center.coordinates.lat}, lng: ${center.coordinates.lng}, zoom: ${zoom}, bearing: ${bearing}, pitch: ${pitch}";
+  }
+}

ios/Classes/MapEvents+JSON.swift

@@ -15,6 +15,19 @@ extension EventTimeInterval {
     }
 }
 
+extension MapboxMaps.CameraState {
+
+    var toJSON: [String: Any] {
+        return [
+            "center": center.toDict(),
+            "padding": ["top": padding.top, "left": padding.left, "bottom": padding.bottom, "right": padding.right],
+            "zoom": zoom,
+            "bearing": bearing,
+            "pitch": pitch
+        ]
+    }
+}
+
 extension MapboxMaps.CanonicalTileID {
     var toJSON: [String: Any] {
         [
@@ -65,7 +78,8 @@ extension StyleDataLoaded: MapEventEncodable {
 extension CameraChanged: MapEventEncodable {
     var toJSON: [String: Any?] {
         [
-            "timestamp": timestamp.microsecondsSince1970
+            "timestamp": timestamp.microsecondsSince1970,
+            "cameraState": cameraState.toJSON,
         ]
     }
 }

lib/src/events.dart

@@ -95,9 +95,12 @@ class EventTimeInterval {
 class CameraChangedEventData {
   /// The time when the camera was changed.
   final int timestamp;
+  /// The current state of the camera.
+  final CameraState cameraState;
 
   CameraChangedEventData.fromJson(Map<String, dynamic> json)
-      : timestamp = json['timestamp'];
+      : timestamp = json['timestamp'],
+        cameraState = Conversion.fromJson(json['cameraState']);
 }
 
 /// The class for map-idle event in Observer

lib/src/extensions.dart

@@ -10,6 +10,27 @@ extension Conversion on CameraState {
       pitch: pitch,
     );
   }
+
+  static CameraState fromJson(Map<String, dynamic> json) {
+    return CameraState(
+        center: Point.fromJson(json['center']),
+        padding: MbxEdgeInsetsCodable.fromJson(json['padding']),
+        zoom: json['zoom'].toDouble(),
+        bearing: json['bearing'].toDouble(),
+        pitch: json['pitch'].toDouble());
+  }
+}
+
+extension MbxEdgeInsetsCodable on MbxEdgeInsets {
+
+  static MbxEdgeInsets fromJson(Map<String, dynamic> json) {
+    return MbxEdgeInsets(
+      top: json["top"].toDouble(),
+      left: json["left"].toDouble(),
+      bottom: json["bottom"].toDouble(),
+      right: json["right"].toDouble(),
+    );
+  }
 }
 
 extension ScreenBoxToJson on ScreenBox {

test/events_test.dart

@@ -3,9 +3,26 @@ import 'package:test/test.dart';
 
 void main() {
   test('CameraChangedEventData fromJson', () {
-    var cameraChangedEventData =
-        CameraChangedEventData.fromJson(<String, dynamic>{'timestamp': 1});
+    final json = {
+      'timestamp': 1,
+      'cameraState': {
+        'center': {'coordinates': [0, 0]},
+        'padding': {'top': 0, 'left': 1, 'bottom': 2, 'right': 3},
+        'zoom': 11,
+        'bearing': 0,
+        'pitch': 0,
+      },
+    };
+    var cameraChangedEventData = CameraChangedEventData.fromJson(json);
     expect(cameraChangedEventData.timestamp, 1);
+    expect(cameraChangedEventData.cameraState.center.coordinates, Position.of([0, 0]));
+    expect(cameraChangedEventData.cameraState.padding.top, 0);
+    expect(cameraChangedEventData.cameraState.padding.left, 1);
+    expect(cameraChangedEventData.cameraState.padding.bottom, 2);
+    expect(cameraChangedEventData.cameraState.padding.right, 3);
+    expect(cameraChangedEventData.cameraState.zoom, 11);
+    expect(cameraChangedEventData.cameraState.bearing, 0);
+    expect(cameraChangedEventData.cameraState.pitch, 0);
   });
 
   test('MapIdleEventData fromJson', () {