Changing control font size

[Andreas Höschler]

Hi all,

I am building a GNUstep app on Ubuntu 20.04 and would like the font used by 
NSButtons, NSTableView, NSComboBox etc. to be larger as normal for industrial 
usage of the app (better readability from further away from the screen).

I found this list 
> NSBoldFontSize
> NSControlContentFontSize
> NSFontSize
> NSLabelFontSize
> NSMenuFontSize
> NSMiniFontSize
> NSMessageFontSize
> NSPaletteFontSize
> NSSmallFontSize
> NSTitleBarFontSize
> NSToolTipsFontSize
> NSUserFixedPitchFontSize
> NSUserFontSize
and greped through the GNUstep sources for NSControlContentFontSize but only 
found 

        grep -r "NSControlContentFontSize" /usr/src/GNUstep/

/usr/src/GNUstep/libs-gui/Source/NSFont.m:    <item>NSControlContentFontSize  
(none)</item>
/usr/src/GNUstep/libs-gui/Source/NSToolbarItem.m:  // [NSFont 
smallSystemFontSize] or better should be NSControlContentFontSize

Is this default used at all? How would I programmatically change the font size 
for all the controls in the user interface. I intuitively tried 

   [[NSUserDefaults standardUserDefaults] setObject:[NSNumber 
numberWithFloat:20.0] forKey:NSControlContentFontSize];
   [[NSUserDefaults standardUserDefaults] setObject:[NSNumber 
numberWithFloat:20.0] forKey:NSLabelFontSize];

but this of course does not build since NSControlContentFontSize is undefined. 

I am obviously missing the point!? :-(

Any idea?

Thanks a lot, 

 Andreas