change the "Dashed border"

["zhenghe zhang" <zhenghe zhang gmail com>]

Hi all
        Now I have a problem, could you help me? Thank you.
As followed;
There is a button, and the button obtains the focus, there is a "Dashed
border" on the button, 
Now I want to change it to "solid line", but I don't know how to do it,
I hope you tell me your methods.
Thank you very much
zh