How to use CanExecuteChangedEventManager

I can't figure out how to use the CanExecuteChangedEventManager in MyCommand : ICommand. I tried the following but value is the wrong type:

public event EventHandler CanExecuteChanged
{
    add
    {
        CanExecuteChangedEventManager.AddHandler(this, value);
    }
    remove
    {
        CanExecuteChangedEventManager.RemoveHandler(this, value);
    }
}

The class I'm writing will look like this but without leaks if possible:

public class ManualRelayCommand : ICommand
{
    // CanExecute() and Execute() excluded
    public event EventHandler CanExecuteChanged;

    public virtual void RaiseCanExecuteChanged()
    {
        var handler = CanExecuteChanged;
        if (handler != null)
        {
            Application.Current.Dispatcher.InvokeAsync(() => handler(this, EventArgs.Empty));
        }
    }
}