dispose method
override
This function cleans up properties of this controller before garbage collection happens.
Implementation
@override
void dispose() {
arcGISMap = null;
_backgroundGrid.invalidateCache();
_arcGISMap.invalidateCache();
_geometryEditor.invalidateCache();
_locationDisplay.invalidateCache();
__viewInsets.invalidateCache();
_geometryEditorChangedSubscription?.cancel();
super.dispose();
}