[Solved] ERROR "Operation could destabilize the runtime." shows when trying to open menu

[Todor]

Hello guys,

I am writing a Custom Control and I use your ContextMenu. In that control I have 2 buttons. Button 1 has a ContextMenu attached. I want to show the ContextMenu under Button 1 when I click Button 2, so I created a custom event and a public method to Button 1, that looks like this:

public delegate void ShowContextMenuHandler(object sender);
public event ShowContextMenuHandler ShowContextMenuEvent;

protected void OnShowContextMenu(object sender)
{
    if (ShowContextMenuEvent != null)
    {
        ShowContextMenuEvent(sender);
    }
}

public void ShowContextMenu()
{
    OnShowContextMenu(this);
}

In the .cs file of the Custom Control I handle the Click Event of Button 2:

btnMenu.Click += new RoutedEventHandler(btnMenu_Click);

void btnMenu_Click(object sender, RoutedEventArgs e)
{
    btnMain.ShowContextMenu();
}

And the declaration of the menu looks like this:

<my:ButtonLeft Height="30"
           Width="91"
           Content="Save"
           x:Name="btnMain">
    <telerik:RadContextMenu.ContextMenu>
        <telerik:RadContextMenu x:Name="DropDownContextMenu"
                    EventName="ShowContextMenuEvent"
                    Placement="Bottom">
            <telerik:RadMenuItem Header="Save"/>
            <telerik:RadMenuItem Header="Save as..."/>
            <telerik:RadMenuItem IsEnabled="False" Header="Don't Save"/>
        </telerik:RadContextMenu>
    </telerik:RadContextMenu.ContextMenu>
</my:ButtonLeft>

But when I click Button 2, I get this exception:

"An exception of type 'System.Security.VerificationException' occurred in DynamicTypes but was not handled in user code
Additional information: Operation could destabilize the runtime."

And it is pointing to my "ShowContextMenuEvent(sender);" line in the "OnShowContextMenu(object sender)" method.

Any idea what am I doing wrong ? It it is a bug into the ContextMenu ?

[Hristo]

Hi Todor,

RadContextMenu uses reflection in order to attach handler to the event that will trigger menu opening. So we are expecting that the handler will have two parameters - sender and event args.
In order to run your code you should change the event handler for the ShowContextMenuEvent to match the standard event handler signature:

public class ButtonLeft : Button
{
    public delegate void ShowContextMenuHandler(object sender, EventArgs e);
    public event ShowContextMenuHandler ShowContextMenuEvent;

    protected void OnShowContextMenu(object sender)
    {
        if (ShowContextMenuEvent != null)
        {
            ShowContextMenuEvent(sender, EventArgs.Empty);
        }
    }

    public void ShowContextMenu()
    {
        OnShowContextMenu(this);
    }
}

Let me know if you have other problems.

Greetings,
Hristo
the Telerik team

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[Todor]

Hi Hristo,
I thought that this might be the case, but I wasn't sure of the default structure you use. Thanks, I will try it and report if I have any other problems. Keep up the good work !