ios - Dragging and dropping not working in Xcode -

i'm working on first swift project in xcode , running trouble dragging , dropping elements storyboard code.

nothing happens when try dragging , dropping. i'm running newest version of xcode , using swift.

the class viewcontroller , file viewcontroller.swift

i'm trying drag , drop textfield class.

i have question , possible solution you, sam.

what system using this? when first started wanted use mac on remote connection , found holding control , dragging yielded me no blue line associate interface builder items assistant editor's code. tried chrome remote desktop, splash top, , vnc viewer. nothing yielded results looking for. when got own mac , working machine able control-click-and-drag associate interface builder items code.

also, using assistant editor or dragging file in navigator on left? haven't tried latter... ever used assistant editor.

hope helps!