UITextDragDelegate.swift

extension ViewController: UITextDragDelegate {
    func textDraggableView(_ textDraggableView: UIView & UITextDraggable, dragPreviewForLiftingItem item: UIDragItem, session: UIDragSession) -> UITargetedDragPreview? {
        
        let dragView = textDraggableView
        
        let selectionRange = textDraggableView.selectedTextRange
        let selectionRects = textDraggableView.selectionRects(for: selectionRange!) as! [UITextSelectionRect]
        
        var array: [CGRect] = []
        
        for r in selectionRects {
            array.append(r.rect)
        }
        
        let paramaters = UIDragPreviewParameters(textLineRects: array as [NSValue])
        
        let textViewCopy = UITextView(frame: textDraggableView.frame)
    
        let attributedString = NSMutableAttributedString(attributedString: dragTextView.attributedText)
        
        let fullRange = attributedString.mutableString.range(of: dragTextView.text)
        let selectedRange = dragTextView.selectedRange
        attributedString.addAttribute(NSAttributedStringKey.foregroundColor, value: UIColor.white, range: fullRange)
        attributedString.addAttribute(NSAttributedStringKey.foregroundColor, value: UIColor.blue, range: selectedRange)
        
        textViewCopy.attributedText = attributedString
        
        
        let target = UIDragPreviewTarget(container: self.view, center: dragTextView.center)
        
        let targeDragView = UITargetedDragPreview(view: textViewCopy, parameters: paramaters, target: target)
        
        return targeDragView
    }
    
    func textDraggableView(_ textDraggableView: UIView & UITextDraggable, itemsForDrag dragRequest: UITextDragRequest) -> [UIDragItem] {
        
        self.range = dragRequest.dragRange
        
        if let string = dragTextView.text(in: dragRequest.dragRange) {
            let itemProvider = NSItemProvider(object: string as NSString)
            return [UIDragItem(itemProvider: itemProvider)]
        }else{
            return []
        }
        
    }
}