+void Panel::grab_focus(Widget &wdg)
+{
+ list<Widget *>::iterator i=find(children.begin(), children.end(), &wdg);
+ if(i==children.end())
+ throw InvalidState("That Widget is not in this Panel");
+
+ set_input_focus(&wdg);
+ if(parent)
+ parent->grab_focus(*this);
+}
+