ArcGIS Pro 3.0 API Reference Guide
ArcGIS.Desktop.Mapping Namespace / MappingExtensions Class / AddOverlay Method / AddOverlay(MapView,Geometry,CIMSymbolReference,Double,Double) Method
The view to add the overlay.
The geometry of the overlay.
The symbol to use for the overlay.
Map reference scale or -1
Visibility factor for showing the overlay through other objects when obscured in 3D.
Valid range is [0..1], any other value will be treated as 0 (not visible).
Example

In This Topic
    AddOverlay(MapView,Geometry,CIMSymbolReference,Double,Double) Method
    In This Topic
    Add an overlay graphic to the map view.
    Syntax
    Public Overloads Shared Function AddOverlay( _
       ByVal mapView As MapView, _
       ByVal geometry As Geometry, _
       ByVal symbol As CIMSymbolReference, _
       ByVal referenceScale As Double, _
       ByVal showThrough As Double _
    ) As IDisposable

    Parameters

    mapView
    The view to add the overlay.
    geometry
    The geometry of the overlay.
    symbol
    The symbol to use for the overlay.
    referenceScale
    Map reference scale or -1
    showThrough
    Visibility factor for showing the overlay through other objects when obscured in 3D.
    Valid range is [0..1], any other value will be treated as 0 (not visible).

    Return Value

    An object that when disposed will remove the overlay.
    Remarks
    When the referenceScale is not equal to -1, the overlay will be created in real world units relative to the provided map reference scale (referenceScale). Otherwise, the overlay will be created in units of points. This is only supported in 2D.
    Example
    Graphic Overlay
    //Defined elsewhere
    private IDisposable _graphic = null;
    public async void GraphicOverlaySnippetTest()
    {
      // get the current mapview and point
      var mapView = MapView.Active;
      if (mapView == null)
        return;
      var myextent = mapView.Extent;
      var point = myextent.Center;
    
      // add point graphic to the overlay at the center of the mapView
      _graphic = await QueuedTask.Run(() =>
      {
        //add these to the overlay
        return mapView.AddOverlay(point,
            SymbolFactory.Instance.ConstructPointSymbol(
                    ColorFactory.Instance.RedRGB, 30.0, SimpleMarkerStyle.Star).MakeSymbolReference());
      });
    
      // update the overlay with new point graphic symbol
      MessageBox.Show("Now to update the overlay...");
      await QueuedTask.Run(() =>
      {
        mapView.UpdateOverlay(_graphic, point, SymbolFactory.Instance.ConstructPointSymbol(
                                      ColorFactory.Instance.BlueRGB, 20.0, SimpleMarkerStyle.Circle).MakeSymbolReference());
      });
    
      // clear the overlay display by disposing of the graphic
      MessageBox.Show("Now to clear the overlay...");
      _graphic.Dispose();
    
    }
    Requirements

    Target Platforms: Windows 11, Windows 10, Windows 8.1

    See Also