For this, you'll need to edit the control template of the EventContainerTemplate and edit the selected visual state.
You can find the template on line 824
ResourceDictionary (if you're not familiar with using the Implicit styles from a XAML file instead of the theme's DLL, see here for instructions
Alternatively, if you want to keep using the Theme DLL, you can copy out the template and add it to your app. For your convenience, I have included the entire template in the attached demo.
To keep this as simple as possible and not change any of the control's parts, I just added an animation to the Selected VisualState
... so that if selection occurs, change the Rectange named "Background" to use my custom brush for it's Fill property.
Here's a screenshot:
I've attached a demo, go to App.xaml
to see the style and template. You can find the added animation on line 67
Lance | Tech Support Engineer, Sr.
Telerik by Progress
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