/// <summary>
/// Invoked when the capability value need.
/// </summary>
/// <param name="e">Information about the capability that was changed.</param>
protected virtual void OnCapabilityValueNeeded(CapabilityEventArgs e)
{
}
/// <summary>
/// Invoked when the capability value changed.
/// </summary>
/// <param name="e">Information about the capability that was changed.</param>
protected virtual void OnCapabilityChanged(CapabilityEventArgs e)
{
}