/// <summary>
 /// Called by Framework when ArcGIS Pro is closing
 /// </summary>
 /// <returns>False to prevent Pro from closing, otherwise True</returns>
 protected override bool CanUnload()
 {
     MapViewInitializedEvent.Unsubscribe(OnMapViewInitialized);
     MapMemberPropertiesChangedEvent.Unsubscribe(OnMapMemberPropertiesChanged);
     MapClosedEvent.Unsubscribe(OnMapClosed);
     //return false to ~cancel~ Application close
     return(true);
 }
        protected override async void Uninitialize()
        {
            await RemoveLayersAsync(true);

            MapViewInitializedEvent.Unsubscribe(OnMapViewInitialized);
            MapClosedEvent.Unsubscribe(OnMapClosedDocument);
            base.Uninitialize();
        }