extend funcitionality of Designer widgets

[dexli]

Place a base class for your widget on the form and invoke the context menu on it.

Thanks a lot.

How can I mark this thread as solved ?

[stampede]

And if you have to change the layout all the work is gone because this file is overwritten by the designer

Nothing is gone, because designer form is used only to manage layout, not behavior of widgets. If you want to change the layout, you just have to edit .ui file, implementation for the class (.cpp / .h ) is left untouched, only ui_*.h is automatically generated, but I don't think anyone edits this file by hand. Right click and "Promote to..." is what you are looking for.

[wysota]

but I don't think anyone edits this file by hand

Unfortunately lots of people do it.