Using virtual member functions

Hello all,

I’m about to use member functions of the abstract base class of qtgui
classes to adjust visualization parameters such as “set_title”,

There is an explanation of virtual based classes in [1]. So it’s
to use pure virtual functions by the derived classes.

When we’re in GNURadio, there is an abstract class and an implementation
class which is derived from the abstract class. So I expect to be able
using the pure virtual functions declared in abstract class by having a
pointer of the implementation class. However the members aren’t
What can I do to use them?



When you ‘make’ a block, it actually returns you a _impl version of the
class, even though only the abstract class is declared publically. All
the methods are actually defined in the _impl, where also the members

If you’re having trouble understanding the polymorphism concepts, I
suggest having another look at some C++ literature. If it’s the actual
GNU Radio block design, have another look at examples of blocks (e.g. in
gr-blocks) to see how the abstract methods interact with their


This forum is not affiliated to the Ruby language, Ruby on Rails framework, nor any Ruby applications discussed here.

| Privacy Policy | Terms of Service | Remote Ruby Jobs