uiimage添加到uitextview并使用Drag，swift调整图像大小

Question

我有这段代码，我从图书馆读取图像，我希望通过拖动（实时）来调整uitextview中的图像大小。有谁知道我该怎么做？

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
            let pickedImage = info[UIImagePickerControllerOriginalImage] as? UIImage

let attachment = NSTextAttachment()
        attachment.image = pickedImage
        //calculate new size.  (-10 because I want to have a litle space on the right of picture)
        let newImageWidth = (txtEditor.bounds.size.width - 10 )
        let scale = newImageWidth/(pickedImage?.size.width)!
        let newImageHeight = (pickedImage?.size.height)! * scale
        //resize this
        attachment.bounds = CGRect.init(x: 0, y: 0, width: newImageWidth, height: newImageHeight)
        //put your NSTextAttachment into and attributedString
        let attString = NSAttributedString(attachment: attachment)
        //add this attributed string to the current position.
        txtEditor.textStorage.insert(attString, at: txtEditor.selectedRange.location)
}