topic Re: Toggle visibility of graphic in GraphicsLayer in ArcGIS API for Silverlight Questions

Toggle visibility of graphic in GraphicsLayer

KiaPierce — Fri, 09 Mar 2012 13:17:52 GMT

Is there a way to toggle the visibility of a graphic in a GraphicsLayer?

Re: Toggle visibility of graphic in GraphicsLayer

deleted-user-ATjHIWsdQYmT — Fri, 09 Mar 2012 13:28:06 GMT

GraphicsLayer has a visible property. You could bind the visibility to a checkbox or whatever control you want.
http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.GraphicsLayer_members.html

Re: Toggle visibility of graphic in GraphicsLayer

KiaPierce — Fri, 09 Mar 2012 13:44:24 GMT

Thanks Andrew. However, there are a few cases in our app where we would like to toggle the visibility of an individual graphic within a GraphicsLayer and not the visiblity of the entire GraphicsLayer. Is there a way to do this?

Re: Toggle visibility of graphic in GraphicsLayer

deleted-user-ATjHIWsdQYmT — Fri, 09 Mar 2012 14:48:40 GMT

Thanks Andrew. However, there are a few cases in our app where we would like to toggle the visibility of an individual graphic within a GraphicsLayer and not the visiblity of the entire GraphicsLayer. Is there a way to do this?

What you could do is loop through all of the graphics in your graphics layer and when you find the one you want to toggle (based on a specific attribute for instance) you could change it's symbology to transparent. Then to toggle it back on, iterate through your graphics in your Graphics Layer again, and change it's symbology back.

for each gr as graphic in trycast(map.layers("MyGraphicsLayer"),graphicslayer)     if gr.Attributes("NAME") = "TargetGraphic" Then         if checkbox.isChecked = true then            gr.symbol = CType(LayoutRoot.Resources("TransparentSymbol"),ESRI.ArcGIS.Client.Symbols.SimpleFillSymbol)        else           gr.symbol = CType(LayoutRoot.Resources("DefaultSymbol"),ESRI.ArcGIS.Client.Symbols.SimpleFillSymbol)        end if      end if next

Re: Toggle visibility of graphic in GraphicsLayer

KiaPierce — Tue, 13 Mar 2012 12:11:58 GMT

Awesome. Thanks Andrew

Re: Toggle visibility of graphic in GraphicsLayer

MaximMikhisor — Mon, 13 Oct 2014 23:49:09 GMT

Type typeInQuestion = typeof(Graphic);

PropertyInfo field = typeInQuestion.GetProperty("Visibility", BindingFlags.NonPublic | BindingFlags.Instance);

field.SetValue(graphic, Visibility.Collapsed);

Re: Toggle visibility of graphic in GraphicsLayer

dotMorten_esri — Tue, 14 Oct 2014 23:16:06 GMT

@Maxim: Note that changing internal properties through reflection can cause a lot of problems - You're really pulling the rug out under the SDK. Also not that these internals might not be available in future updates.

Re: Toggle visibility of graphic in GraphicsLayer

LanceCrumbliss — Thu, 16 Oct 2014 16:04:06 GMT

I could be wrong but if a GraphicsLayer is using a Renderer, then an individual graphic's symbol property will be null (or maybe it has changed or even "fixed" if that wasn't ESRI's original intention) so the method you suggest may not always be applicable.

In any case, I found this on another post somewhere and it works great. Basically, setting the geometry to null hides the symbol. This also doesn't require any reflection; it's pure OO inheritance.

Public Class ExtendedGraphic

Inherits ESRI.ArcGIS.Client.Graphic

Private _storedGeometry As ESRI.ArcGIS.Client.Geometry.Geometry

Public Property Visible() As Boolean

Get

Return Me.Geometry IsNot Nothing

End Get

Set(ByVal value As Boolean)

If value <> Visible Then

If value Then

If _storedGeometry IsNot Nothing Then Me.Geometry = _storedGeometry

Else

If Me.Geometry IsNot Nothing Then _storedGeometry = Me.Geometry

Me.Geometry = Nothing

End If

End Set

End Property

End Class