Noticed that from time to time and was wondering if there are already known ways for improvement.
Windows x64; not specific to 2.2 (occurs with 2.0.12 too), but i did never see it with Delphi.
Have a form with a treeview (inside a TPanel, or a TSCrollBox, or standalone without container).
When doubleclicking on the caption bar, so maximizing the window, for a noticeable period of time a black region inside the maximized window can be seen.
See the screenshot catching the moment when the wm_size message is arriving.
Of course it's not functionally relevant. But it's not nice either and i would be interested to know if it could be improved.
Tried typical candidates for improvement (DoubleBuffer; intercepting the WM_ERASEBKGND message; setting Params.WindowClass.hbrBackground := COLOR_BTNFACE + 1); playing with ParentBackground et.al., but no change.
I'm wondering where the black erasure color at the end comes from and why it's so reluctant to change it.
A test project is attached.
My question is: can anybody confirm the observation? And does anybody have an explanation or knows a workaround so that at least the background erasure doesn't use a black brush color but a white color?
Remark: as told, it was not with Delphi apps.
Second: the only way to change it i saw was to set params.exstyle to WS_EX_TRANSPARENT, but that leads to other trouble, starting from disappearing scrollbars etc. (not a desired approach)