Can you programmatically change the button image for a ESRI.ArcGIS.Desktop.AddIns.Button?

I'm new to the AddIn customization model in ArcGIS 10 and I'm trying to figure out how to change a button image for a button. I'm looking for the equivalent to the BaseCommand UpdateBitmap method and haven't had any luck. Is this a limitation of the AddIn model? Or did I miss something obvious?

Ok, I've worked something out using ICommandItem.FaceID. I wasn't initially thinking of using ICommandItem, but it gets the job done.

ICommandItem commandItem = ArcMap.Application.Document.CommandBars.Find(...;


I have not worked with add-ins in ArcGIS 10, but looking at the documentation (see heading Add-in file anatomy), it appears that you would need to specify the image declaratively in the add-in's XML configuration (metadata):

<ESRI.Configuration
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

<!-- Omitted -->

<ArcMap>
<Commands>
<Button
id="Acme_ToggleDockWinBtn"
class="ToggleDockWinBtn"
caption="OpenDockWin"
category="Acme Tools"
image="Images\ToggleDockWinBtn.png" <!-- Define image URI -->
tip="Toggle dockable window."
message="Open dockable window.">
<Help heading="Toggle">Turns the ACME dockable window on and off.</Help>
</Button>
</Commands>
</ArcMap>