i have lazarus trunk revision 57333 and observe strange screen flickering with a DBGrid and Oracle Database connection.

See Revision 57000 without flickering

https://drive.google.com/file/d/1671s-JuIM5z7KkwRU8pbX6Nqt53sDACI/view?usp=sharing

( hope that link is ok )

compare with Revision 57333,  heavy screen flickering

https://drive.google.com/file/d/1yZHltOBPt47i6S2jeovGu9W3ScUX8-Zg/view?usp=sharing

Info:

Lazarus 1.9.0 57333 FPC 3.0.4 i386-win32-win32/win64

Windows XP SP3

No flickering with same app and Windows 2003 !!

This report is about the same issue:
https://bugs.freepascal.org/view.php?id=33198

Landmesser John wrote

Lazarus 1.9.0 57333 FPC 3.0.4 i386-win32-win32/win64 Windows XP SP3 No flickering with same app and Windows 2003 !!

Maybe the solution should be specific to LCL-Win32 and Windows version.

Juha

the delivered patch in https://bugs.freepascal.org/view.php?id=33198 is:

Index: grids.pas
===================================================================
--- grids.pas    (revision 57332)
+++ grids.pas    (working copy)
@@ -9414,6 +9414,8 @@
  procedure TCustomGrid.Loaded;
  begin
    inherited Loaded;
+  if not (csDesigning in ComponentState) then
+    DoubleBuffered := DoubleBuffered or
(GetSystemMetrics(SM_REMOTESESSION)=0); // force DoubleBuffered if not
used in remote session
    VisualChange;
  end;

but in Grid.pas Revision 57333

procedure TCustomGrid.Loaded;
begin
   inherited Loaded;
   VisualChange;
end;

so the patch was never applied??

patch applied to my local copy of lcl --> issue is gone !!