I recently submitted a forum post asking how I could set images on my menu items via CSS (using sprites):
http://www.telerik.com/community/forums/thread/b311D-behdtb.aspx
The recommended solution did work, the only downside being that, in order to make it work, I had to assign an ImageUrl that pointed to a clear gif image on every menu item (without an ImageUrl the img tag isn't even rendered). This is inconvenient, but at least it does work and allows me to have a single sprite image for all of my menus and context menus.
I now want to achieve the same effect with my tree nodes. Rather than assigning a different image to each node via the ImageUrl property, I want to have a single sprite image. The problem is that when I set the CssClass on each node, it ends up being applied to the span tag surrounding the text of the node, instead of the div tag that surrounds the text and the image of the node as I would've expected. Given this, I now do not know/if I can achieve the result I desire.
I love where Telerik has gone w/ the sprite approach, and the performance benefits that developers can gain from it, but it seems that your support for it is not quite complete in your control set. As I recommended in my other forum post, I think that the RadMenuItem and RadTreeNode objects should have ImageCssClass properties to make it easy for us to consolidate all of our images for our RadMenus and RadTreeViews into a single sprite image.
Please let me know if you have a recommended workaround for doing sprite-based RadTreeView images.
Thanks,
Ross