如何使用nsattributedstring在Swift中将图像添加为文本附件

我正在尝试使用我作为按钮放入的图像为iOS构建自定义键盘。 当我按下按钮时，链接到按钮的图像被放入一个属性字符串，该字符串被加载到自定义键盘视图内的UiTextView中。 那很有效。

问题是，当我将新图像附加到属性字符串时，字符串中的旧图像和新图像都将更改为我当前按下的图像。 我无法理解为什么字符串中的旧图像会发生变化。

有什么建议么？ 我尝试过使用replaceCharactersInRange和insertAttributedString但无法使其工作。 这是代码（在viewDidLoad之后）：

let textAttachment = NSTextAttachment() let textView = UITextView(frame: CGRectMake(5, 5, 200, 40)) var attributedString = NSMutableAttributedString(string: "") @IBAction func buttonPressed(button :UIButton) { let string = button.titleLabel?.text textAttachment.image = UIImage(named: "\(string!).png")! textAttachment.image = UIImage(CGImage: textAttachment.image!.CGImage!, scale: 6, orientation: .Up) let attrStringWithImage = NSAttributedString(attachment: textAttachment) attributedString.appendAttributedString(attrStringWithImage); textView.attributedText = attributedString; } 

谢谢！

Answer 1

我们不能简单地附加NSTextAttachment图像 。我们必须将所有附加的图像和连接存储到现有的属性String。

 func buttonPressed(_ sender: Any) { let button = sender as! UIButton let tag = button.tag let attributedString:NSAttributedString! switch tag { case 2: attributedString = addAttributedText(text: (button.titleLabel?.text)!) case 3: attributedString = addAttributedText(text: (button.titleLabel?.text)!) case 4: attributedString = addAttributedText(text: (button.titleLabel?.text)!) default: attributedString = addAttributedText(text: "launch") } textView.attributedText = attributedString } func addAttributedText(text:String) -> NSAttributedString { textViewDidChange(textView) let axtractedImageAttribute = NSMutableAttributedString() for image in imageArray { let attachment:NSTextAttachment = NSTextAttachment() attachment.image = image attachment.setImageHeight(height: 20) let attachmentString:NSAttributedString = NSAttributedString(attachment: attachment) axtractedImageAttribute.append(attachmentString) } let attachment:NSTextAttachment = NSTextAttachment() attachment.image = UIImage(named: "\(text).png") attachment.setImageHeight(height: 20) let attachmentString:NSAttributedString = NSAttributedString(attachment: attachment) let attributedString:NSMutableAttributedString = NSMutableAttributedString(string:textView.text!) attributedString.append(axtractedImageAttribute) attributedString.append(attachmentString) return attributedString } //MARKS:- Extract attachedImage func textViewDidChange(_ textView: UITextView) { imageArray = [UIImage]() let range = NSRange(location: 0, length: textView.attributedText.length) if (textView.textStorage.containsAttachments(in: range)) { let attrString = textView.attributedText var location = 0 while location < range.length { var r = NSRange() let attrDictionary = attrString?.attributes(at: location, effectiveRange: &r) if attrDictionary != nil { let attachment = attrDictionary![NSAttachmentAttributeName] as? NSTextAttachment if attachment != nil { if attachment!.image != nil { imageArray.append( attachment!.image!) } } location += r.length } } } } } 

演示参考

Answer 2

我发现了问题，我需要为NSTextAttachment设置不同的变量（即textAttachment1，textAttachment2等），否则它只使用第一个被寻址的图像。

Answer 3

这对我有用：

 let attributedStringTextAttachment = NSTextAttachment() attributedStringTextAttachment.image = UIImage(named: "image")