Drawing a polygon on the screen
The following code draws a polygon on the screen in the map where the mouse is clicked. The x,y coordinates come from a mousedown click event when the user interacts with the application. In this example, the polygon is not persisted on the screen but is removed after the next screen refresh.
[VB.NET]
Public Sub DrawPolygon(ByVal activeView As ESRI.ArcGIS.Carto.IActiveView)
If activeView Is Nothing Then
Return
End If
Dim screenDisplay As ESRI.ArcGIS.Display.IScreenDisplay = activeView.ScreenDisplay
' Constant.
screenDisplay.StartDrawing(screenDisplay.hDC, CShort(ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache))
Dim rgbColor As ESRI.ArcGIS.Display.IRgbColor = New ESRI.ArcGIS.Display.RgbColorClass
rgbColor.Red = 255
Dim color As ESRI.ArcGIS.Display.IColor = rgbColor ' Implicit cast.
Dim simpleFillSymbol As ESRI.ArcGIS.Display.ISimpleFillSymbol = New ESRI.ArcGIS.Display.SimpleFillSymbolClass
simpleFillSymbol.Color = color
Dim symbol As ESRI.ArcGIS.Display.ISymbol = TryCast(simpleFillSymbol, ESRI.ArcGIS.Display.ISymbol) ' Dynamic cast.
Dim rubberBand As ESRI.ArcGIS.Display.IRubberBand = New ESRI.ArcGIS.Display.RubberPolygonClass
Dim geometry As ESRI.ArcGIS.Geometry.IGeometry = rubberBand.TrackNew(screenDisplay, symbol)
screenDisplay.SetSymbol(symbol)
screenDisplay.DrawPolygon(geometry)
screenDisplay.FinishDrawing()
End Sub
[C#]
public void DrawPolygon(ESRI.ArcGIS.Carto.IActiveView activeView)
{
if (activeView == null)
{
return ;
}
ESRI.ArcGIS.Display.IScreenDisplay screenDisplay = activeView.ScreenDisplay;
// Constant.
screenDisplay.StartDrawing(screenDisplay.hDC, (System.Int16)
ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache); // Explicit cast.
ESRI.ArcGIS.Display.IRgbColor rgbColor = new ESRI.ArcGIS.Display.RgbColorClass();
rgbColor.Red = 255;
ESRI.ArcGIS.Display.IColor color = rgbColor; // Implicit cast.
ESRI.ArcGIS.Display.ISimpleFillSymbol simpleFillSymbol = new
ESRI.ArcGIS.Display.SimpleFillSymbolClass();
simpleFillSymbol.Color = color;
ESRI.ArcGIS.Display.ISymbol symbol = simpleFillSymbol as
ESRI.ArcGIS.Display.ISymbol; // Dynamic cast.
ESRI.ArcGIS.Display.IRubberBand rubberBand = new
ESRI.ArcGIS.Display.RubberPolygonClass();
ESRI.ArcGIS.Geometry.IGeometry geometry = rubberBand.TrackNew(screenDisplay,
symbol);
screenDisplay.SetSymbol(symbol);
screenDisplay.DrawPolygon(geometry);
screenDisplay.FinishDrawing();
}
See Also:
How to draw a point on the screenHow to draw a polyline on the screen
How to draw a rectangle on the screen
Development licensing | Deployment licensing |
---|---|
ArcGIS for Desktop Basic | ArcGIS for Desktop Basic |
ArcGIS for Desktop Standard | ArcGIS for Desktop Standard |
ArcGIS for Desktop Advanced | ArcGIS for Desktop Advanced |
Engine Developer Kit | Engine |