/// <summary>
        /// Called when the value of the SelectedItem property changes.
        /// </summary>
        /// <param name="d">DynamicSeries that changed its SelectedItem.</param>
        /// <param name="e">Event arguments.</param>
        private static void OnSelectedItemPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            DataPointSeries source   = (DataPointSeries)d;
            object          oldValue = (object)e.OldValue;
            object          newValue = (object)e.NewValue;

            source.OnSelectedItemPropertyChanged(oldValue, newValue);
        }
        /// <summary>
        /// IsSelectionEnabledProperty property changed handler.
        /// </summary>
        /// <param name="d">DynamicSeries that changed its IsSelectionEnabled.
        /// </param>
        /// <param name="e">Event arguments.</param>
        private static void OnIsSelectionEnabledPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            DataPointSeries source   = (DataPointSeries)d;
            bool            oldValue = (bool)e.OldValue;
            bool            newValue = (bool)e.NewValue;

            source.OnIsSelectionEnabledPropertyChanged(oldValue, newValue);
        }