Hello SivaPrasad Bevara,
This appears to be a bug in the RadColorPalleteView. We logged it in our PITS(ColorPicker: RadColorPaletteView `s SelectionChanged event fires twice) and updated your telerik points accordingly. You will be soon able vote for this issue ( it will be uploaded in the next 24 hours). As a workaround you can do like so:
sender, Telerik.Windows.Controls.SelectionChangedEventArgs e)
if(this.palette.SelectedItem != null)
string strColor = ((RadColorPaletteView)e.OriginalSource).SelectedItem.ToString();
Please accept our apologies for the inconvenience caused and feel free to ask if you need further help.
the Telerik team
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