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222

answers:

2

When I minimize and restore my Delphi application, the window contents flash a horrible black before (re)painting on Vista/Win7. This can also be seen with the Delphi 2007 IDE - the Object Inspector, Project Manager, Messages window (but not the editor contents) also flash black when restoring.

None of the ususal flicker-free painting techniques seem to make any difference, and some even make it worse: DoubleBuffered, WS_EX_COMPOSITED, WM_ERASEBKGND, etc.

Most Microsoft applications do not exhibit this behavior. Is this a problem with Delphi's implementation of Windows forms? Does anyone know of a workaround?

A: 

I would check that you have current video drivers and review all the settings. I have never seen the effect you describe on these OS, either with Delphi or my own apps; and if it was a widespread problem I feel sure that the Embarcadero newsgroups would be full of it.

frogb
A: 

I have D2007 and D2010 on two machines (Win7 64-bit laptop and Vista 32-bit desktop), and don't have this problem on either of them in either the IDEs or my applications.

Do you have theme support/Aero enabled? What video card and drivers? Are you using the classic appearance in Windows?

Ken White
The two machines I can observe it on both have themes enabled, and both have ATI cards with the latest drivers. On the machine with 2x4890 Crossfire the flash is quicker, but still noticable. I'll look for it on other machines.
avenmore