[Qt-interest] Promoting custom widgets in designer

[Friedemann Kleint]

Hi,

> I see exactly what you are describing.  Is there is some additional
> way to integrate
> custom widgets into designer that makes available the promotion
> functionality? I have no idea one way or the other.  (It looks to me more
> like a
> design limitation
> than an outright bug, but maybe it is supposed to work.)

Promoted widgets and custom widgets are used interchangeably in Qt Designer. 
If a custom widgets cannot be instantiated (indicating that the plugin is 
missing), it becomes a promoted widget and vice versa, a custom widget is 
instantiated if it matches a previously promoted widget. This is to make 
working with UI-files in varying installations smoother.  

However, as it is currently implemented, it requires that the base class of a 
promoted/custom widget is a class provided by the Qt library, which can always 
be instantiated. Therefore, the limitation of not being able to further 
promote custom widgets exists.

Regards,
Friedemann
-- 
Friedemann Kleint
Nokia, Qt Development Frameworks