topic Re: Graphic tool - Draw Polygon Polygon disappears after finish drawing in ArcGIS API for Silverlight Questions

Graphic tool - Draw Polygon Polygon disappears after finish drawing

YingLin — Wed, 23 Mar 2011 19:44:05 GMT

I am using arcGIS silverlight api 2.1 SDK. Created a button for drawing polygon using ESRI:RedlineAction

<esri:RedlineAction
    Color="Red"
    DrawMode="Polygon"
    GraphicsLayerID="MyGraphicsLayer"
    TargetName="Map" />

when drawing is finished, the polygon disappears. I want it to stay so that it can be used when creating printouts. Drawing with polyline and freehand functions are fine though. Anyone has the same problem?
Thanks very much

Re: Graphic tool - Draw Polygon Polygon disappears after finish drawing

JenniferNery — Sat, 11 Dec 2021 12:35:08 GMT

If you are using this SDK sample: http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#GraphicsActions

                                <i:Interaction.Triggers>
                                    <i:EventTrigger EventName="Click">
                                        <esri:RedlineAction 
                                    Color="#FF32FF00"
                                    DrawMode="Polygon"                                    
                              GraphicsLayerID="MyGraphicsLayer"
                                    TargetName="MyMap"/>
                                    </i:EventTrigger>
                                </i:Interaction.Triggers>

Notice that the GraphicsLayer it uses is:

            <esri:GraphicsLayer ID="MyGraphicsLayer" Renderer="{StaticResource GraphicsLayerLineSymbol}" />

This Renderer is for Polyline geometry. The graphic is not removed, it is just not rendered because its geometry type cannot be given line symbol. You need to use a different Renderer with symbols that match the geometry type for graphics drawn by RedlineAction.

Re: Graphic tool - Draw Polygon Polygon disappears after finish drawing

YingLin — Thu, 24 Mar 2011 15:39:00 GMT

Does that mean another graphics Layer have to be created for polygon rendering? The previous api example was able to accommadate both polyline and polygon on same graphic layer.
thanks

Re: Graphic tool - Draw Polygon Polygon disappears after finish drawing

dotMorten_esri — Thu, 24 Mar 2011 15:49:36 GMT

If you use one of the built-in renderers, the symbol type much match the geometry type, and thus all geometry types must be the same in the layer.

If you don't use a renderer, you can simply assign a symbol directly to each graphic that matches for the geometry type.