Overriding some C++ class methods

Hi. I am a bit new to C++ so i would like to ask if someone knows the following: I want to override only one method of a widget in Qt library. To do this i create my own class, which inherits that widget, and i declare just that one method in my new class. The problem is that the compiler (g++) complains about the constructors. Do i need also to override ALL the constructors of that widget? (there are many of them). If so, isn't there another way of implementing this? I mean just to override the method that i am interested in and not any other thing in that widget class. Thanks.