ProSnippets GraphicsLayers
Language: C#
Subject: GraphicsLayers
Contributor: ArcGIS Pro SDK Team <[email protected]>
Organization: Esri, http://www.esri.com
Date: 11/7/2025
ArcGIS Pro: 3.6
Visual Studio: 2022
if (map.MapType != MapType.Map)
return;// not 2D
var gl_param = new GraphicsLayerCreationParams { Name = "Graphics Layer" };
// Note: must be called on the QueuedTask
{
//By default will be added to the top of the TOC
graphicsLayer = LayerFactory.Instance.CreateLayer<ArcGIS.Desktop.Mapping.GraphicsLayer>(gl_param, map);
//Add to the bottom of the TOC
gl_param.MapMemberIndex = -1; //bottom
LayerFactory.Instance.CreateLayer<ArcGIS.Desktop.Mapping.GraphicsLayer>(gl_param, map);
//Add a graphics layer to a group layer...
var group_layer = map.GetLayersAsFlattenedList().OfType<GroupLayer>().First();
LayerFactory.Instance.CreateLayer<ArcGIS.Desktop.Mapping.GraphicsLayer>(gl_param, group_layer);
//TODO...use the graphics layer
//
// or use the specific CreateGroupLayer method
LayerFactory.Instance.CreateGroupLayer(map, -1, "Graphics Layer");
}if (map.MapType != MapType.Map)
{
// not 2D - could be a scene - no graphics layers
}
//get the first graphics layer in the map's collection of graphics layers
graphicsLayer = map.GetLayersAsFlattenedList().OfType<GraphicsLayer>().FirstOrDefault();
if (graphicsLayer != null)
{
//TODO...use the graphics layer
}
//Or, Get and set the graphic layer that acts as the target for interactive drawing tools.
targetGraphicsLayer = map.TargetGraphicsLayer; // get the target graphics layer
map.TargetGraphicsLayer = graphicsLayer; // set the target graphics layer// Note: must be called on the QueuedTask
{
var elems = sourceGraphicsLayer.FindElements(new List<string>() { "Point 1", "Line 3", "Text 1" });
var copiedElements = targetGraphicsLayer.CopyElements(elems);
}// Note: must be called on the QueuedTask
{
graphicsLayer.RemoveElements(graphicsLayer.GetSelectedElements());
}// Note: must be called on the QueuedTask
{
//Place symbol in the center of the map
var extent = MapView.Active.Extent;
var location = extent.Center;
//specify a symbol
var pt_symbol = SymbolFactory.Instance.ConstructPointSymbol(
ColorFactory.Instance.GreenRGB);
//create a CIMGraphic
var graphic = new CIMPointGraphic()
{
Symbol = pt_symbol.MakeSymbolReference(),
Location = location //center of map
};
graphicsLayer.AddElement(graphic);
}// Note: must be called on the QueuedTask
{
//On the QueuedTask
//Place a line symbol using the extent's lower left and upper right corner.
var extent = MapView.Active.Extent;
//get the lower left corner of the extent
var pointFromCoordinates = new Coordinate2D(extent.XMin, extent.YMin);
//get the upper right corner of the extent
var pointToCoordinates = new Coordinate2D(extent.XMax, extent.YMax);
List<Coordinate2D> points = new List<Coordinate2D> { pointFromCoordinates, pointToCoordinates };
//create the polyline
var lineSegment = PolylineBuilderEx.CreatePolyline(points);
//specify a symbol
var line_symbol = SymbolFactory.Instance.ConstructLineSymbol(
ColorFactory.Instance.GreenRGB);
//create a CIMGraphic
var graphic = new CIMLineGraphic()
{
Symbol = line_symbol.MakeSymbolReference(),
Line = lineSegment,
};
graphicsLayer.AddElement(graphic);
}// Note: must be called on the QueuedTask
{
//On the QueuedTask
//Place a polygon symbol using the mapview extent geometry
var extent = MapView.Active.Extent;
//Contract the extent
var polygonEnv = extent.Expand(-100000, -90000, false);
//create a polygon using the envelope
var polygon = PolygonBuilderEx.CreatePolygon(polygonEnv);
//specify a symbol
var poly_symbol = SymbolFactory.Instance.ConstructPolygonSymbol(
ColorFactory.Instance.GreenRGB);
//create a CIMGraphic
var graphic = new CIMPolygonGraphic()
{
Symbol = poly_symbol.MakeSymbolReference(),
Polygon = polygon,
};
graphicsLayer.AddElement(graphic);
}// Note: must be called on the QueuedTask
{
//Place a multipoint graphic using the mapview extent geometry
var extent = MapView.Active.Extent;
//Contract the extent
var polygonEnv = extent.Expand(-100000, -90000, false);
//create a polygon using the envelope
var polygon = PolygonBuilderEx.CreatePolygon(polygonEnv);
//Create MultipPoints from the polygon
var multiPoints = MultipointBuilderEx.CreateMultipoint(polygon);
//specify a symbol
var point_symbol = SymbolFactory.Instance.ConstructPointSymbol(
ColorFactory.Instance.GreenRGB);
//create a CIMGraphic
var graphic = new CIMMultipointGraphic
{
Symbol = point_symbol.MakeSymbolReference(),
Multipoint = multiPoints
};
graphicsLayer.AddElement(graphic);
}// Note: must be called on the QueuedTask
{
//Place symbol in the center of the map
var extent = MapView.Active.Extent;
var location = extent.Center;
//specify a symbol
var pt_symbol = SymbolFactory.Instance.ConstructPointSymbol(
ColorFactory.Instance.GreenRGB);
graphicsLayer.AddElement(location, pt_symbol);
}// Note: must be called on the QueuedTask
{
//Place symbol in the center of the map
var extent = MapView.Active.Extent;
var location = extent.Center;
//specify a text symbol
var text_symbol = SymbolFactory.Instance.ConstructTextSymbol
(ColorFactory.Instance.BlackRGB, 8.5, "Corbel", "Regular");
graphicsLayer.AddElement(location, text_symbol, "Text Example");
}//Point Feature layer to convert into graphics
var lyr = MapView.Active?.Map?.GetLayersAsFlattenedList().OfType<FeatureLayer>().FirstOrDefault(s => s.ShapeType == esriGeometryType.esriGeometryPoint);
if (lyr == null) return;
// Note: must be called on the QueuedTask
{
//Point symbol for graphics
var pointSymbol = SymbolFactory.Instance.ConstructPointSymbol(CIMColor.CreateRGBColor(100, 255, 40), 10, SimpleMarkerStyle.Circle);
//Collection to hold the point graphics
var listGraphicElements = new List<CIMGraphic>();
//Iterate through each point feature in the feature layer
using (RowCursor rows = lyr.Search()) //execute
{
int i = 0;
while (rows.MoveNext())
{
using var feature = rows.Current as Feature;
//Create a point graphic for the feature
var crimePt = feature.GetShape() as MapPoint;
if (crimePt != null)
{
var cimGraphicElement = new CIMPointGraphic
{
Location = crimePt, //MapPoint
Symbol = pointSymbol.MakeSymbolReference()
};
//Add the point feature to the collection
listGraphicElements.Add(cimGraphicElement);
i++;
}
}
}
//Magic happens...Add all the features to the Graphics layer
graphicsLayer.AddElements(listGraphicElements);
}var elements = graphicsLayer.GetElementsAsFlattenedList()
.Where(e => e.Name.StartsWith("Text"));
// Note: must be called on the QueuedTask
{
graphicsLayer.SelectElements(elements);
//or select one element
graphicsLayer.SelectElement(elements.FirstOrDefault());
}// Note: must be called on the QueuedTask
{
//Find elements by name
var elems = graphicsLayer.FindElements(new List<string>() { "Point 1", "Line 3", "Text 1" });
//Find elements by type
//Find all point graphics in the Graphics Layer
var pointGraphics = graphicsLayer.GetElementsAsFlattenedList().Where(elem => elem.GetGraphic() is CIMPointGraphic);
//Find all line graphics in the Graphics Layer
var lineGraphics = graphicsLayer.GetElementsAsFlattenedList().Where(elem => elem.GetGraphic() is CIMLineGraphic);
//Find all polygon graphics in the Graphics Layer
var polygonGraphics = graphicsLayer.GetElementsAsFlattenedList().Where(elem => elem.GetGraphic() is CIMPolygonGraphic);
//Find all text graphics in the Graphics Layer
var textGraphics = graphicsLayer.GetElementsAsFlattenedList().Where(elem => elem.GetGraphic() is CIMTextGraphic);
//Find all picture graphics in the Graphics Layer
var pictureGraphic = graphicsLayer.GetElementsAsFlattenedList().Where(elem => elem.GetGraphic() is CIMPictureGraphic);
}//Map Tool is used to perform Spatial selection.
//Graphic selection uses the selection geometry
//to intersect the geometries of those elements (graphic or group)
//that will be selected and then highlights them.
{
var selPoly = geometry as Polygon;
// Note: must be called on the QueuedTask
{
//note: the selected elements may belong to more than one layer...
var elems = MapView.Active.SelectElements(selPoly, SelectionCombinationMethod.New);
}
}// Note: must be called on the QueuedTask
{
//Create an extent to use for the spatial selection
var extent = MapView.Active.Extent;
var selectionExtent = extent.Expand(0.5, 0.5, true);
//Select elements in specified graphics layer using the selection extent.
var selectedElements = MapView.Active.SelectElements(graphicsLayer, selectionExtent, SelectionCombinationMethod.Add);
}var all_text = graphicsLayer.GetElementsAsFlattenedList()
.Where(e => e.GetGraphic() is CIMTextGraphic);//unselect the first element in the currently selected elements
var elem = graphicsLayer.GetSelectedElements().FirstOrDefault();
// Note: must be called on the QueuedTask
{
if (elem != null)
//Unselect one element
graphicsLayer.UnSelectElement(elem);
//unselect all elements
graphicsLayer.UnSelectElements();
//equivalent to
graphicsLayer.ClearSelection();
}ArcGIS.Desktop.Layouts.Events.ElementEvent.Subscribe((args) =>
{
//check if the container is a graphics layer - could be a Layout (or even map view)
if (args.Container is ArcGIS.Desktop.Mapping.GraphicsLayer graphicsLayer)
{
//get the total selection count for the container
var count = args.Elements.Count();
//Check count - could have been an unselect or clearselect
if (count > 0)
{
//this is a selection or add to selection
var elems = graphicsLayer.GetSelectedElements();
//TODO process the selection...
}
else
{
//This is an unselect or clear selection
//TODO process the unselect or clear select
}
}
});// Note: must be called on the QueuedTask
{
var elemsToGroup = graphicsLayer.GetSelectedElements();
//group elements
groupElement = graphicsLayer.GroupElements(elemsToGroup);
}// Note: must be called on the QueuedTask
{
var selectedElements = graphicsLayer.GetSelectedElements().ToList(); ;
if (selectedElements?.Any() == false)//must be at least 1.
return;
var elementsToUnGroup = new List<GroupElement>();
//All selected elements should be grouped.
if (selectedElements.Count() == selectedElements.OfType<GroupElement>().Count())
{
//Convert to a GroupElement list.
elementsToUnGroup = selectedElements.ConvertAll(x => (GroupElement)x);
}
if (elementsToUnGroup.Count() == 0)
return;
//UnGroup
graphicsLayer.UnGroupElements(elementsToUnGroup);
}//check the parent
var parent = groupElement.Elements.First().GetParent();//will be the group element
//top-most parent
var top_most = groupElement.Elements.First().GetParent(true);//will be the GraphicsLayer// Note: must be called on the QueuedTask
{
//get the current selection set
var sel_elems = graphicsLayer.GetSelectedElements();
//can they be brought forward? This will also check that all elements have the same parent
if (graphicsLayer.CanBringForward(sel_elems))
{
//bring forward
graphicsLayer.BringForward(sel_elems);
//bring to front (of parent)
//graphicsLayer.BringToFront(sel_elems);
}
else if (graphicsLayer.CanSendBackward(sel_elems))
{
//send back
graphicsLayer.SendBackward(sel_elems);
//send to the back (of parent)
//graphicsLayer.SendToBack(sel_elems);
}
}// Note: must be called on the QueuedTask
{
var selElementsZOrder = graphicsLayer.GetSelectedElements();
//list out the z order
foreach (var elem in selElementsZOrder)
System.Diagnostics.Debug.WriteLine($"{elem.Name}: z-order {elem.ZOrder}");
}// Note: must be called on the QueuedTask
{
//Each selected element will move to a set distance to the upper right.
var selElements = graphicsLayer.GetSelectedElements();
if (selElements.Count == 0) return;
//Move the element up
foreach (var selElement in selElements)
{
//Get the element's bounds
var elementPoly = PolygonBuilderEx.CreatePolygon(selElement.GetBounds());
//get the coordinates of the element bounding envelope.
var pointsList = elementPoly.Copy2DCoordinatesToList();
//Move the element's Anchor point to the upper right.
selElement.SetAnchorPoint(pointsList[1]);
}
}// Note: must be called on the QueuedTask
{
//within a queued Task
//get the first line element in the layer
var ge = graphicsLayer.FindElement("Line 10") as GraphicElement;
var graphic = ge.GetGraphic();
if (graphic is CIMLineGraphic lineGraphic)
{
//change its symbol
lineGraphic.Symbol =
SymbolFactory.Instance.ConstructLineSymbol(
SymbolFactory.Instance.ConstructStroke(
ColorFactory.Instance.BlueRGB, 2, SimpleLineStyle.DashDot)).MakeSymbolReference();
//apply the change
ge.SetGraphic(lineGraphic);
}
} 