Trouble with CanExecute

[KarenEllett]

I'm trying to alter the relationship query example so that the tool is only enabled for a couple of specific layers.  I've tried several different ways of specifying it, but no luck.   return popupInfo.PopupItem.LayerName.ToString() == "MyLayerName"; etc.

Can anyone give me some help/examples? 
Thanks!

[JohanCarlsson]

I'd recommend getting the layer type instead.

        public bool CanExecute(object parameter)
        {
            return MapApplication.Current.SelectedLayer is SomeLayerType;
        }

Alternatively you could get the layer name:
MapApplication.GetLayerName(yourLayer) == "the layer you want active";