System.Object
   System.EventArgs
      C1.Xaml.Chart.Interaction.PositionChangedArgs
   Windows.UI.Xaml.DependencyObject
      C1.Xaml.Chart.Interaction.TranslateBehavior
      C1.Xaml.Chart.Interaction.ZoomBehavior
      Windows.UI.Xaml.UIElement
         Windows.UI.Xaml.FrameworkElement
            Windows.UI.Xaml.Controls.Control
               C1.Xaml.C1RangeSlider
                  C1.Xaml.Chart.Interaction.C1AxisScrollbar
                  C1.Xaml.Chart.Interaction.C1RangeSelector
               C1.Xaml.Chart.Interaction.C1LineMarker

Reference

C1.UWP.FlexChart Assembly