Graphics Layer inaccessible by background thread

Question

Hi All,

I am using ArcGis API for WPF in a desktop based application to show locations, route for the stops on a 2D Map.
A background thread fetches the locations (along with lat-long) from a WCF service. Then these locations are displayed on the Map as TextSymbol(s) on a GraphicLayer.
Then another background thread calls a WCF RESTfull resource to find route for the locations (stops). This call returns me a route which i am trying to display on the map using another GraphicLayer using 'Add' method of the 'Graphics' property of the layer. Whenever i try to do so, i get an exception 'The calling thread cannot access this object because a different thread owns it.'
I have tried to use Dispatcher object for the screen, the map object, the graphics layer but none seems to work for me.

MichaelBranscomb · Answer

Hi,

I haven't had a chance to read the whole thread here - but you might want to take a look at the synchronization context info in http://forums.arcgis.com/threads/60409-Is-it-possible-to-edit-file-gdb-feature-classes-from-Windows-Service.

Cheers

Mike

LorenCress · Answer

Isn't the System.Action Anonymous and takes 0 args?

would we have to create a new delegate with a Graphic set as one of the args....

??? I have been trying to get this to work for days now and still can't seem to get this thing going 😞

System.Action is anonymous in this example, but it can take an argument (or more than one, if needed; see the link), so it doesn't need to have a delegate.

BrianLocke · Answer

Isn't the System.Action Anonymous and takes 0 args?

would we have to create a new delegate with a Graphic set as one of the args....

??? I have been trying to get this to work for days now and still can't seem to get this thing going 😞