Hi, I am trying to call a Property with INotifyProperty Changed from ClassB to ClassA, but this doesn't work!! What am I doing wrong?

Code:
Public Class ClassA
Implements System.ComponentModel.INotifyPropertyChanged

Public Event PropertyChanged(ByVal sender As Object, ByVal e As
System.ComponentModel.PropertyChangedEventArgs) Implements
System.ComponentModel.INotifyPropertyChanged.PropertyChanged
...