Question

I have four UserControls in my WPF Application – e.g.

VisualA, VisualB, VisualC, VisualD

I want each of them need to inherit a generic “Player” Class which contains a heap of shared code -. e.g. methods, timers etc

So far this is what I have tried in my Control’s XAML

<UserControl x:Class="VisualA"

And here is what I have in a separate Class file.

Partial Public Class VisualA
    Inherits Player
End Class

Public Class Player
    Inherits UserControl
End Class

In my Window, I’m referencing the UserControl as normal:

<local:VisualA></local:VisualA>

But, I’m getting the following error:

Base class ‘System.Windows.Controls.UserControl’ specified for class
‘VisualA’ cannot be different from the base class ‘Player’ of one of
its other partial types

What am I doing wrong?

I was also under the impression any code (i.e. methods) inside the inherited class (Player) would be able to access the Controls in the UserControl by referencing by name – is that correct?

Answer 1

The base class in the XAML is still set to UserControl. Change it to Player. Also note that the namespace for the Player type will have to be defined. i.e:

<BaseClasses:Player x:Class="VisualA"
        xmlns:BaseClasses="clr-namespace:MyProject.BaseClasses" 
        ... all your other namespaces used