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Qt-interest Archive, April 2007
Qt 4.2 Windows - using getDC() in a paint event causes flicker

• Subject: Qt 4.2 Windows - using getDC() in a paint event causes flicker
• From: Paul Miller <paul@xxxxxxxxxx>
• Date: Wed, 04 Apr 2007 12:59:08 -0500
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I'm trying to call a special platform-dependent drawing function in a Qt 
4.2 app for Windows.

I am calling getDC() and passing that into the drawing function, then 
calling releaseDC().

I can see the picture being drawn with that function if I move the mouse 
in/out of my window, but it displays once and then flickers off.

Does this have something to do with Qt's compositing stuff?

What is the proper way to use a platform dependent rendering function 
that uses the widget's platform-dependent DC?

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