WPF Custom TextBox ContextMenuOpening Problem

I've got an issue with a custom control that I've written not firing it's ContextMenuOpening event when I hook it up programatically. The control is basically a wrapper for the standard TextBox:

public class MyTextBox : TextBox
{
    public MyTextBox()
    {
        this.ContextMenuOpening += new ContextMenuEventHandler(MyTextBox_ContextMenuOpening);
    }

    void MyTextBox_ContextMenuOpening(object sender, ContextMenuEventArgs e)
    {
        MessageBox.Show("ContextMenuOpening event fired");
    }
}

There's nothing suspect either about the XAML:

<local:MyTextBox Height="25" Width="300"/>

For some reason though, I can never get the event to fire. I'm trying to intercept the context menu so I can alter it (it's context sensitive) and 开发者_JS百科really am trying to avoid having to hook up the event everywhere the control is used - surely this is possible?

Turns out you need to explicity set the ContextMenu to null when creating the object:

public MyTextBox()
{
    this.ContextMenu = null;
    this.Initialized += (s, e) =>
        ContextMenuOpening += new ContextMenuEventHandler(MyTextBox_ContextMenuOpening);
}

Then it works a treat :)

The ContextMenuOpening-Event will only be fired after you assign a new context menu to the property ContextMenu:

public MyTextBox()
{
    this.ContextMenu = new ContextMenu();
    this.ContextMenu.Items.Add(new MenuItem {Header = "Do stuff"});
    
    ...
}