[Qt-interest] Mark active Dock widgets, MDI subwindows

[Ole Streicher]

Hi,

My application consists on a number of QDockWidgets or QMdiSubWindows,
depending on users preferences. Menu and toolbar actions shall be
executed for the active widget/window.

The problem is now: how can the user recognize which widget/window is
active? At least, in the default KDE style all widgets/windows look the
same independently of whether they are active.

This is especially problematic for QDockWidgets because the active
window may be hidden by another widget if they are tabbed. In that case
the action goes into an invisible widget, what is far from being
intuitive. 

I tried to set the BackgroundRole of the active widget to "Highlight",
but this is ugly (and probably against any style guide) in the MDI case,
and for QDockWidgets the BackgroundRole is ignored at all.

What would be the best way to mark the active QDockWidget/QMdiSubWindow?

Best regards

Ole