Hi Harinath Reddy,
You should pass the clicked customer as a Command Parameter, but to do this you'll have to handle the Opened event of the RadContextMenu and get it with GetClickedElement<RadTileViewItem>() method. You can't go around this event handler in the code behind because in some point you'll have get the visually clicked element and this can't be done in the ViewModel.
For further references could you please examine the attached project and if you have more questions feel free to ask.
the Telerik team
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