package greenfoot.event;

import java.util.EventListener;




| Listener to be notified when something changes from a valid state to invalid or vice versa.
|
| @author Poul Henriksen
|
public interface ValidityListener
extends EventListener{    
   


| Change from invalid to valid.
|
public void changedToValid(ValidityEvent e);
    
   
   


| Change from valid to invalid.
|
public void changedToInvalid(ValidityEvent e); 
   }