NSTextAttachment: その概要とiOSでテキストに画像を追加する方法

let attachment = NSTextAttachment()
attachment.image = UIImage(named: "icon-star")

let attachmentString = NSAttributedString(attachment: attachment)

let text = NSMutableAttributedString(string: "Rating: ")
text.append(attachmentString)

let label = UILabel()
label.attributedText = text

let attachment = NSTextAttachment()
attachment.image = UIImage(named: "icon-star")

let font = UIFont.systemFont(ofSize: 16)
let fontCapHeight = font.capHeight
let imageSize = CGSize(width: 18, height: 18)

attachment.bounds = CGRect(
    x: 0,
    y: (fontCapHeight - imageSize.height) / 2,
    width: imageSize.width,
    height: imageSize.height
)

guard let pdfData = Bundle.main.url(forResource: "document",
                                  withExtension: "pdf") else { return }

let fileData = Data(contentsOf: pdfData)
let attachment = NSTextAttachment(data: fileData,
                                       ofType: "com.adobe.pdf")

attachment.bounds = CGRect(x: 0, y: -4,
                           width: 24, height: 24)

let pdfString = NSAttributedString(attachment: attachment)

func textView(_ textView: UITextView,
                shouldInteractWith attachment: NSTextAttachment,
                in characterRange: NSRange,
                interaction: UITextItemInteraction) -> Bool {
    if interaction == .preview {
        return false
    }
    // 詳細画面を開く
    showImageDetail(attachment.image)
    return false
}