pygtk: What class should my custom widgets inherit from?

Question

When making a custom widget in pygtk, what class should it inherit from? I want to be able to put the widget inside other widgets, but I don't want other people to put stuff in mine. Usually I make my widgets inherit from gtk.HBox or gtk.VBox, and that works fine, but it is possible then for someone to do a pack_start() on my widget and cause strange things to happen. I'd inherit from gtk.Widget but then how do I add things to it? I'd inherit from gtk.Container or gtk.Bin but the docs say they are abstract classes.

Answer 1

If your custom widget contains other (probably standard) widgets, you could simply raise an exception in the overridden pack_ methods. That way, nobody can put stuff in it (easily). Inside your class, you then have to use super(...).pack_xxx instead of self.pack_xxx.

But it's probably better to derive from gtk.Container. Then you'll have to implement its abstract methods like do_add(self, widget).

In case you only draw custom content (no children), there's no need to derive from a container widget. See the tutorial on pygtk.org.