Minor issues with CreateSystemImageSet

[pyscripter]

Minor issues with CreateSystemImageSet

[joachimmarder]

Thanks, issue 1 and 2 are addressed.

Incidentally it is also worth moving UpdateHeaderRect() after the inherited call

Agreed.

Instead of using CurrentPPI it is faster ....

I don't think we should do preemptive performance optimization here.

and more reliable to use FCurrentPPI

Can you explain why? Given general best practices, one should use the property, not the member variable.

[pyscripter]

@joachimmarder
Thanks for the changes!

I don't think we should do preemptive performance optimization here.

It is not about optimization. As explained in #1205 FCurrentPPI is a protected field and CurrentPPI is a property that gets the PPI from the control handle. The former is more reliable and consistent with the current control scaling state. So, if you can (meaning if FCurrentPPI has been updated by the inherited ChangeScale), you should use FCurrentPPI instead of CurrentPPI.

On Issue 2:
You can significantly simplify the code by not checking IsSystemStyle and just using StyleServices.GetElementSize, Please see above.

In other words the following:

      if StyleServices.IsSystemStyle then
      begin
        {$if CompilerVersion >= 33}
        if TOSVersion.Check(10) and (TOSVersion.Build >= 15063)  then
          Theme := OpenThemeDataForDPI(Handle, 'BUTTON', CurrentPPI)
        else
        {$ifend}
          Theme := OpenThemeData(Self.Handle, 'BUTTON');
        Details := StyleServices.GetElementDetails(tbCheckBoxUncheckedNormal);
        Res := GetThemePartSize(Theme, BM.Canvas.Handle, Details.Part, Details.State, nil, TS_TRUE, lSize) = S_OK;
      end
      else

can just be removed!