How to change the alpha of Popup header in Flex
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I want to make the header of a pop-up less transparent than the default one. Please see below image:

![enter image description here][1]

I can read the text written beneath it. Is there a way i can change the Alpha of it. I tried changing the header color using following:

    titleWin.setStyle("headerColors",  [blue, blue]);


But it is still showing the header as transparent. Please help!!

  [1]: http://i.stack.imgur.com/gZ7cO.png