What's wrong with declaration of this routed event?

Question

I've created the following UserControl:

public partial class ReplacementPatternEditor : UserControl, INotifyPropertyChanged
{
    ....

    public static readonly RoutedEvent CollectionChanged = EventManager.RegisterRoutedEvent(
        "CollectionChanged", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(ReplacementPatternEditor));

    void RaiseCollectionChangedEvent()
    {
        RoutedEventArgs newEventArgs = new RoutedEventArgs(ReplacementPatternEditor.CollectionChanged);
        RaiseEvent(newEventArgs);
    }

    ...
}

Now, when I try to use this routed event inside my xaml code:

<local:ReplacementPatternEditor ItemsSource="{Binding MyItemSource}" CollectionChanged="OnCollectionChanged"/>

I'm getting following error at compilation:

The property 'CollectionChanged' does not exist in XML namespace 'clr-namespace:MyNamespace'

Why am I getting this, and how do I make the routed events work?

Mark Hall · Accepted Answer · 2012-05-15T21:24:08.837

Looking at this MSDN Link. It talks about registering a handler which you have done, then it talks about providing the CLR Accessors for the event which I don't see in your code. Then it adds the Event handler. You do not have an Event declaration

i.e. something like this

public static readonly RoutedEvent CollectionChangedEvent = EventManager.RegisterRoutedEvent( 
    "CollectionChanged", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(ReplacementPatternEditor)); 

public event RoutedEventHandler CollectionChanged
{
    add { AddHandler(CollectionChangedEvent, value); } 
    remove { RemoveHandler(CollectionChangedEvent, value); }
}


void RaiseCollectionChangedEvent() 
{ 
    RoutedEventArgs newEventArgs = new RoutedEventArgs(ReplacementPatternEditor.CollectionChanged); 
    RaiseEvent(newEventArgs); 
}

What's wrong with declaration of this routed event?

1 Answers1