RFC: About custom widgets in designer / KDevelop4

Andreas Pakulat apaku at gmx.de
Sun Jul 8 12:07:56 UTC 2007

On 08.07.07 13:26:47, Jonas Widarsson wrote:
> Earlier email on kde-devel triggered me.
> On Saturday 07 July 2007, Andreas Pakulat wrote:
> > On 07.07.07 13:51:54, dukju ahn wrote:
> > > Hi. I happen to write custom widget. That new custom widget has
> > > its own .ui, .h and .cpp files. And this widget is contained by other
> > > widget using QtDesigner. I used "promote" feature in designer,
> > > because custom widget are not displayed in designer unless I
> > > write separate plugin (which is difficult).
> >
> > I disagree. Its really simple, just create a QDesignerCustomWidgetPlugin
> > (exact name may differ) and implement the needed methods (as per
> > designer manual). Compile it into a shared object (don't forget the
> > Q_.. macro in the .cpp) and put it into a path that is contained in
> First of all, I'd like to point out that a manual designer custom widget 
> plugin enabling process like that is not nearly "really simple" when you 
> weren't prepared for it and expected a simple mouseclick or drag and drop or 
> something like that, which would by the way more easily fit into the "really 
> simple" category. (Man, I am starting to write like the graphics ninja - 
> never ending sentences)

I still disagree, we're not (just) gui-designers, we're developers, so
writing up a plugin class which needs at most less than a handful of
functions properly implemented is a no-brainer. Especially since the
documentation on this is really extensive (although the docs on a
multi-widget-plugin is not that extensive, last I checked)

> I assume the multiple project support I am starting to hear about can do 
> dependencies ? Relying on that:

Yeap it will.

> As KDE devs are way more likely to produce an intelligent result than those 
> strapped up in that giant organisation, I would propose that KDevelop does 
> this for you. Having a project setting that indicates all widgets meeting the 
> requirements should be put in a plugin library that should as automatically 
> as possible be made available for qt4 designer.

Yes, I have plans for exactly that. However its not clear wether this
will be possible, especially trying to load the new widget into an
existing integrated designer window. (although I think it can be made)

> Or maybe I missed an earlier discussion that already dismisses this idea as 
> bad.

You missed a discussion, but one where the outcome was: Unless we face
technical problems it should be done :)

I'm not sure though it'll happen for 4.0, because we need to save
something for KDevelop4.1 and there's already plenty of things to do for


You are destined to become the commandant of the fighting men of the
department of transportation.

More information about the KDevelop-devel mailing list