changing = function (
   event
Object that contains information about event. Object has the following properties:
 
 
target (object): An object that raised the event.
 
type (string): Event name.
 
data (object): An object that contains data, which were specified when subscribing to the event.
 
originalEvent (object): Original event if event was received from DOM-element.
 
 : object
   eventsArgs
Object that contains event arguments. Object has the following properties:
 
 
actionName (string): Action name. Supported values: "clear", "insert", "removeAt", "move" and "swap".
 
items (object): WebUiElementJS objects, which must be removed. Property is defined for action "clear".
 
index (number): Zero-based image index in collection. Property is defined for actions "insert" and "removeAt".
 
item (object): WebUiElementJS object, which must be inserted/removed/moved. Property is defined for actions "insert", "removeAt" and "move".
 
firstIndex (number): Zero-based index of the first UI element after swapping of elements. Property is defined only for the action "swap".
 
secondIndex (number): Zero-based index of the second UI element after swapping of elements. Property is defined only for the action "swap".
 
previousIndex (number): Zero-based index of UI element before moving of annotation. Property is defined only for the action "move".
 
currentIndex (number): Zero-based index of UI element after moving of annotation. Property is defined only for the action "move".
 
 : object
) { };