[8.0ß16-x32] Flickering CheckBox, ComboBox and RadioBox

umbra · Post by *umbra » 2012-01-20, 01:30 UTC

Every time I move a mouse cursor over some CheckBox, ComboBox or RadioBox, it flickers. This includes command line box and also options in all dialog boxes. Most of the time it's barely visible, but I set up my TC to have a black background so white flashes coming from black command line box are little bit too noticeable.
This applies only to 32b version of TC (including 7.56).

Sir_SiLvA · Post by *Sir_SiLvA » 2012-01-20, 02:06 UTC

Cant confrim that for tc7.56 or 8 on windows xp 32bit

Post by *ghisler(Author) » 2012-01-20, 11:35 UTC

Cannot reprodice either. Please give me more details, like used theme.

umbra · Post by *umbra » 2012-01-20, 13:12 UTC

I have Win7 x64 with enabled Aero theme. However it looks like it's happening only in Aero, because there is no flickering in a Classic theme.
It's happening regardless of my TC settings, but it is much easier to notice with background color set to black.

See this video (not all flashes were recorded, but you still should get the idea):
Video

Post by *ghisler(Author) » 2012-01-20, 13:34 UTC

OK, I will try with black, no problem with white background here.

umbra · Post by *umbra » 2012-01-31, 23:31 UTC

This bug has been moved to " Behaviour which will not be changed". Does it mean that you cannot reproduce it or that it's too complicated to fix? I would just like to know, if there's a chance it will be fixed in some future versions.
BTW, I've noticed that this also happens to tabs, sort columns and standard buttons, but not to toolbar buttons, lists or trees.

Post by *ghisler(Author) » 2012-02-01, 16:12 UTC

I cannot reproduce it when moving the mouse, only when resizing the main window. Is it the same kind of flickering?

umbra · Post by *umbra » 2012-02-01, 17:27 UTC

Resizing the main window causes, that virtually all its elements start to flicker - even those that usually don't (like toolbar or panels).
In this case, even the x64 build has this problem, however it's diametrically less noticeable and not all elements seem to flicker.

Again a video.

To me it looks like the x32 build does a much more of redrawing than the x64 build. I'm not a Delphi developer, but maybe you could add some kind of debug counters to see, how often are the redrawing procedures called and then compare those two builds.

umbra · Post by *umbra » 2012-02-02, 21:34 UTC

Just to be clear - this is not a major issue nor a regression. One can easily get used to it, so it doesn't need to be fixed as soon as possible. The main reason I mentioned it, is that there might be some kind of unnoticed error inside of redrawing code.
Or it's a "feature" of Delphi. Do you know any other maintained application using the same version of Delphi as you do? Maybe I could check, if it has the same problems.