Slider::Listener class makes MainContentComponent Abstract


#1

Hello everybody,

While testing the Slider::Listener class Projucer cant build because of the following error:

it seems to disappear when a delete it from the MainContentComponent.h file
Here is another view of my code:

Regards.


#2

Hi, you are deriving from the Slider::Listener class, when you get an abstract class error this means that one of the classes you are deriving from have one or more virtual functions that isn’t implemented yet. In this case you haven’t implemented the Slider::Listener::sliderValueChanged method in your MainContentComponent yet :slight_smile:


#3

This is expected behaviour. The class Slider::Listener is pure virtual, which means it cannot instanciated until certain methods are implemented. See Slider::Listener:
virtual void sliderValueChanged (Slider *slider)=0 means, that a class that inherits from Slider::Listener must implement this method.


#4

Many thanks!!!