[google_maps_flutter_web] Stop listening to map events when disposed (flutter#9250)

Fixes flutter/flutter#168782

## Pre-Review Checklist

- [/] I read the [Contributor Guide] and followed the process outlined there for submitting PRs.
- [/] I read the [Tree Hygiene] page, which explains my responsibilities.
- [/] I read and followed the [relevant style guides] and ran [the auto-formatter].
- [/] I signed the [CLA].
- [/] The title of the PR starts with the name of the package surrounded by square brackets, e.g. `[shared_preferences]`
- [/] I [linked to at least one issue that this PR fixes] in the description above.
- [/] I updated `pubspec.yaml` with an appropriate new version according to the [pub versioning philosophy], or I have commented below to indicate which [version change exemption] this PR falls under[^1].
- [/] I updated `CHANGELOG.md` to add a description of the change, [following repository CHANGELOG style], or I have commented below to indicate which [CHANGELOG exemption] this PR falls under[^1].
- [/] I updated/added any relevant documentation (doc comments with `///`).
- [/] I added new tests to check the change I am making, or I have commented below to indicate which [test exemption] this PR falls under[^1].
- [/] All existing and new tests are passing.

[^1]: Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling.

Author: JamesMcIntosh

packages/google_maps_flutter/google_maps_flutter_web/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.5.14+1
+
+* Stops processing events and cancels subscriptions when controller is disposed.
+
 ## 0.5.14
 
 * Adds support for disabling or moving the camera control button on web.

packages/google_maps_flutter/google_maps_flutter_web/example/integration_test/google_maps_controller_test.dart

@@ -310,6 +310,46 @@ void main() {
         expect(events[4], isA<CameraIdleEvent>());
       });
 
+      testWidgets('stops listening to map events once disposed', (
+        WidgetTester tester,
+      ) async {
+        controller =
+            createController()
+              ..debugSetOverrides(
+                createMap: (_, __) => map,
+                circles: circles,
+                heatmaps: heatmaps,
+                markers: markers,
+                polygons: polygons,
+                polylines: polylines,
+                groundOverlays: groundOverlays,
+              )
+              ..init();
+
+        controller.dispose();
+
+        // Trigger events on the map, and verify they've been broadcast to the stream
+        final Stream<MapEvent<Object?>> capturedEvents = stream.stream.take(5);
+
+        gmaps.event.trigger(
+          map,
+          'click',
+          gmaps.MapMouseEvent()..latLng = gmaps.LatLng(0, 0),
+        );
+        gmaps.event.trigger(
+          map,
+          'rightclick',
+          gmaps.MapMouseEvent()..latLng = gmaps.LatLng(0, 0),
+        );
+        // The following line causes 2 events
+        gmaps.event.trigger(map, 'bounds_changed');
+        gmaps.event.trigger(map, 'idle');
+
+        final List<MapEvent<Object?>> events = await capturedEvents.toList();
+
+        expect(events, isEmpty);
+      });
+
       testWidgets("binds geometry controllers to map's", (
         WidgetTester tester,
       ) async {

packages/google_maps_flutter/google_maps_flutter_web/lib/src/google_maps_controller.dart

@@ -139,6 +139,11 @@ class GoogleMapController {
   TileOverlaysController? _tileOverlaysController;
   GroundOverlaysController? _groundOverlaysController;
 
+  StreamSubscription<void>? _onClickSubscription;
+  StreamSubscription<void>? _onRightClickSubscription;
+  StreamSubscription<void>? _onBoundsChangedSubscription;
+  StreamSubscription<void>? _onIdleSubscription;
+
   // Keeps track if _attachGeometryControllers has been called or not.
   bool _controllersBoundToMap = false;
 
@@ -247,32 +252,48 @@ class GoogleMapController {
   void _attachMapEvents(gmaps.Map map) {
     map.onTilesloaded.first.then((void _) {
       // Report the map as ready to go the first time the tiles load
-      _streamController.add(WebMapReadyEvent(_mapId));
+      if (!_streamController.isClosed) {
+        _streamController.add(WebMapReadyEvent(_mapId));
+      }
     });
-    map.onClick.listen((gmaps.MapMouseEventOrIconMouseEvent event) {
+    _onClickSubscription = map.onClick.listen((
+      gmaps.MapMouseEventOrIconMouseEvent event,
+    ) {
       assert(event.latLng != null);
-      _streamController.add(
-        MapTapEvent(_mapId, gmLatLngToLatLng(event.latLng!)),
-      );
+      if (!_streamController.isClosed) {
+        _streamController.add(
+          MapTapEvent(_mapId, gmLatLngToLatLng(event.latLng!)),
+        );
+      }
     });
-    map.onRightclick.listen((gmaps.MapMouseEvent event) {
+    _onRightClickSubscription = map.onRightclick.listen((
+      gmaps.MapMouseEvent event,
+    ) {
       assert(event.latLng != null);
-      _streamController.add(
-        MapLongPressEvent(_mapId, gmLatLngToLatLng(event.latLng!)),
-      );
+      if (!_streamController.isClosed) {
+        _streamController.add(
+          MapLongPressEvent(_mapId, gmLatLngToLatLng(event.latLng!)),
+        );
+      }
     });
-    map.onBoundsChanged.listen((void _) {
+    _onBoundsChangedSubscription = map.onBoundsChanged.listen((void _) {
       if (!_mapIsMoving) {
         _mapIsMoving = true;
-        _streamController.add(CameraMoveStartedEvent(_mapId));
+        if (!_streamController.isClosed) {
+          _streamController.add(CameraMoveStartedEvent(_mapId));
+        }
+      }
+      if (!_streamController.isClosed) {
+        _streamController.add(
+          CameraMoveEvent(_mapId, _gmViewportToCameraPosition(map)),
+        );
       }
-      _streamController.add(
-        CameraMoveEvent(_mapId, _gmViewportToCameraPosition(map)),
-      );
     });
-    map.onIdle.listen((void _) {
+    _onIdleSubscription = map.onIdle.listen((void _) {
       _mapIsMoving = false;
-      _streamController.add(CameraIdleEvent(_mapId));
+      if (!_streamController.isClosed) {
+        _streamController.add(CameraIdleEvent(_mapId));
+      }
     });
   }
 
@@ -648,6 +669,14 @@ class GoogleMapController {
     _clusterManagersController = null;
     _tileOverlaysController = null;
     _groundOverlaysController = null;
+    _onClickSubscription?.cancel();
+    _onClickSubscription = null;
+    _onRightClickSubscription?.cancel();
+    _onRightClickSubscription = null;
+    _onBoundsChangedSubscription?.cancel();
+    _onBoundsChangedSubscription = null;
+    _onIdleSubscription?.cancel();
+    _onIdleSubscription = null;
     _streamController.close();
   }
 }

packages/google_maps_flutter/google_maps_flutter_web/pubspec.yaml

@@ -2,7 +2,7 @@ name: google_maps_flutter_web
 description: Web platform implementation of google_maps_flutter
 repository: https://github.com/flutter/packages/tree/main/packages/google_maps_flutter/google_maps_flutter_web
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+maps%22
-version: 0.5.14
+version: 0.5.14+1
 
 environment:
   sdk: ^3.7.0