Max Howell is correct. In native OS X applications, you have got the option to set small and tiny sizes to your windows and widgets. These will then choose smaller fonts and also will resize some of the graphical elements.
Many OS X designers make use of this, and therefore an application which does not follow this conventions is very likely to look oversized on OS X.
As has been noted, Qt does provide widget attributes which can change this: Qt::WA_MacNormalSize
, Qt::WA_MacSmallSize
, Qt::WA_MacMiniSize
, Qt::WA_MacVariableSize
– but unfortunately, it seems that many people don’t know about them and if they do, implementing them is a bit of a hack, as it will require the code to have quite a few #ifdef
s (unless they’re using a helper function for this to reduce the effort).
Particularly bad is that Qt does not use these attributes in their own Qt Creator or Qt Designer either, especially in widgets such as the property tables where the large row height makes it almost useless on smaller monitors, because you’ll need to scroll forever to find the property you’ve been looking for.