I'm not sure that I understand your question. What do you mean with in Loaded event?
You can add the icons in XAML or you can add them in the Page constructor. Just give Name to the contextMenu so that you have access in the code behind and after the InitializeComponent method iterate the Items of the contextMenu and set their Icon property (like in my previous post).
Let me know if you need more help.
the Telerik team
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