Release the map view and the controller when the map leaves the composition

src/main/java/com/mapconductor/mappls/MapplsMapView.kt

@@ -187,6 +187,11 @@ fun MapplsMapView(
         // For now, assuming content relates to overlay definitions.
         style = style,
         onStyleDiagnostics = onStyleDiagnostics,
+        // Never started (onStart is not called), so it is not stopped either --
+        // MapView.onStop() would deactivate the shared FileSource the next map
+        // still uses. Destroying it ends the render thread, whose camera
+        // listeners otherwise keep the controller and every overlay alive.
+        onDestroyMapView = { mapView -> mapView.onDestroy() },
         content = content, // This might need adjustment based on how overlays are handled
     )
 }

src/main/java/com/mapconductor/mappls/MapplsViewStateImpl.kt

@@ -21,7 +21,10 @@ class MapplsViewState(
     cameraPosition: MapCameraPosition = MapCameraPosition.Default,
 ) : MapViewState<MapplsMapDesignTypeInterface>(cameraPosition),
     MapplsViewStateInterface {
-    private var controller: MapplsViewControllerInterface? = null
+    // Read through the base so that letting go of the controller there (MapViewBase
+    // does it when the map is torn down) leaves nothing behind here.
+    private val controller: MapplsViewControllerInterface?
+        get() = attachedMapController as? MapplsViewControllerInterface
     private var _mapDesignType: MapplsMapDesignTypeInterface = mapDesignType
 
     override var mapDesignType: MapplsMapDesignTypeInterface
@@ -32,7 +35,6 @@ class MapplsViewState(
         get() = _mapDesignType
 
     internal fun setController(controller: MapplsViewControllerInterface) {
-        this.controller = controller
         attachController(controller)
     }
 

src/main/java/com/mapconductor/mappls/polygon/MapplsPolygonConductor.kt

@@ -130,7 +130,10 @@ class MapplsPolygonConductor(
         }
 
     override fun destroy() {
-        // No native resources to clean up for polygons
+        // A destroyed conductor can still be referenced (by its map controller,
+        // or a state that has not let go yet); without this it keeps every entity.
+        polygonOverlay.polygonManager.clear()
+        polylineOverlay.polylineManager.clear()
     }
 }