The OnClientDragStart event of the RadWindow fires when the user starts dragging the popup. This action is also initiated by a click or a tap on the title bar.
The event handler receives the following arguments:
The RadWindow object that fired the event.
An event arguments object that does not expose any methods and properties.
You can use this event to get the starting position of the dialog by calling the
getWindowBounds() method from the RadWindow client-side API.