System.Object
   C1.iOS.Input.ComboBoxItemLoadingEventArgs
   Foundation.NSObject
      CoreAnimation.CALayer
         CoreAnimation.CAShapeLayer
            C1.iOS.Input.RoundRectLayer
      UIKit.UIResponder
         UIKit.UIView
            C1.iOS.Input.C1DropDown
               C1.iOS.Input.C1ComboBox
                  C1.iOS.Input.C1AutoComplete
            UIKit.UIControl
               UIKit.UITextField
                  C1.iOS.Core.C1TextField
                     C1.iOS.Input.C1MaskedTextField
                     C1.iOS.Input.C1TextBox
   System.EventArgs
      C1.iOS.Core.AsyncEventArgs
         C1.iOS.Input.AutoCompleteFilteringEventArgs
         C1.iOS.Input.TextBoxAutoCompleteEventArgs
      C1.iOS.Input.CompletedEventArgs
      C1.iOS.Input.DropDownOpenChangedEventArgs
      C1.iOS.Input.DropDownOpenChangingEventArgs
      C1.iOS.Input.TextChangedEventArgs

Reference

C1.iOS.Input Assembly