OwnerDraw with WS_EX_COMPOSITED under XP

Question

I have a static control which has SS_OWNERDRAW and SS_NOTIFY flag when it is crated. Its parent window has WS_EX_COMPOSITED flag.

Under Windows XP, it is not drawn correctly, as the picture below showed (The right-top rectangle):

enter image description here

But under Windows 7, it is drawn correctly, as the picture below showed (The corss "X" on right-top):

enter image description here

How to fix this problem in XP? Furthermore, what causes this problem (in XP)?

Post the owner-draw code. This is probably an alpha-channel mishap. — Cody Gray - on strike, Jun 29 '16 at 16:56

score 1 · Answer 1 · answered Feb 15 '13 at 15:59

1

MSDN for CreateWindowEx() says this:

With WS_EX_COMPOSITED set, all descendants of a window get bottom-to-top painting order using double-buffering. Bottom-to-top painting order allows a descendent window to have translucency (alpha) and transparency (color-key) effects, but only if the descendent window also has the WS_EX_TRANSPARENT bit set. Double-buffering allows the window and its descendents to be painted without flicker.

I.e. the child STATIC control should have WS_EX_TRANSPARENT set.

answered Feb 15 '13 at 15:59

mity

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I tried to use WS_EX_TRANSPARENT, but in XP, it then draw anything, i.e "no corss symbol, no black rectangle, just a static background there" – user565739 Feb 17 '13 at 14:24
But in Windows 7 or 8, there is no problem. – user565739 Feb 17 '13 at 14:25

OwnerDraw with WS_EX_COMPOSITED under XP

1 Answers1