wp7 change background color of control on control disable

i want to change the backgroundcolor of a datepicker when it is disable.

i tried to change the background but

it is n开发者_StackOverflow社区ot changing when it is disabled

how to change it?

If you use Expression Blend to edit the Control template of the DatePicker, then find the Button inside the template and edit it's template. With the template selected open the 'states' panel, select the disabled state and edit the ButtonBackground's background brush property to your desired colour.