我有一个 PDF 图像,已附加到字符串中。我使用 NSTextAttachment 和 NSAttributedString 来完成它。我将它们添加到 textView 中,结果是 Hello,其下方有一个 World 图像。
问题是当我在 textAttachment 上设置 PDF 图像的边界时,World 图像会变形。它被拉得又长又宽。
如何在 textAttachment
对象上设置 contentMode
以使用 .aspectRatio
正确重绘图像?
数字 #4 是我设置界限的地方
// #1. Define dict attribute for string
let bold17 = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: 17)]
// #2. Create "hello" string and add the dict attribute to it
let helloStr = NSAttributedString(string: "Hello\n\n", attributes: bold17)
// #3. Create NSTextAttachment
let textAttachment = NSTextAttachment()
// #4. Add image to the textAttachment then set it's bounds
textAttachment.image = UIImage(named: "world_PDF")
textAttachment.bounds = CGRect(x: 0, y: 0, width: 200, height: 200)
// #5. Set image as NSAttributedString
let worldImage = NSAttributedString(attachment: textAttachment)
// #6. Create NSMutableString to
let mutableAttributedString = NSMutableAttributedString()
// #7. Append the "hello" string and the "world" image to each other using the mutableAttributedString object
mutableAttributedString.append(helloStr)
mutableAttributedString.append(worldImage)
// #8. Set the mutableAttributedString to the textView then center it
textView.attributedText = mutableAttributedString
textView.textAlignment = .center
最佳答案
我遵循了@Maciej Swic的回答
由于某种原因,我无法扩展 NSTextAttachment 类,因此我将其添加到我正在使用它的类的底部。我删除了我在问题中使用的 bounds 属性并使用相反,他的功能。它位于#4,第二行:
class MyController: UIViewController{
override func viewDidLoad() {
super.viewDidLoad()
// #1. Define dict attribute for string
let bold17 = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: 17)]
// #2. Create "hello" string and add the dict attribute to it
let helloStr = NSAttributedString(string: "Hello\n\n", attributes: bold17)
// #3. Create NSTextAttachment
let textAttachment = NSTextAttachment()
// #4. Add image to the textAttachment then set it's bounds
textAttachment.image = UIImage(named: "world_PDF")
textAttachment.setImageHeight(height: 200) // <----HIS ANSWER HERE
// #5. Set image as NSAttributedString
let worldImage = NSAttributedString(attachment: textAttachment)
// #6. Create NSMutableString to
let mutableAttributedString = NSMutableAttributedString()
// #7. Append the "hello" string and the "world" image to each other using the mutableAttributedString object
mutableAttributedString.append(helloStr)
mutableAttributedString.append(worldImage)
// #8. Set the mutableAttributedString to the textView then center it
textView.attributedText = mutableAttributedString
textView.textAlignment = .center
}
}
extension NSTextAttachment {
func setImageHeight(height: CGFloat) {
guard let image = image else { return }
let ratio = image.size.width / image.size.height
bounds = CGRect(x: bounds.origin.x, y: bounds.origin.y, width: ratio * height, height: height)
}
}
关于ios - Swift iOS - 如何将 NSTextAttachment 内容模式设置为 Aspect Fit?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/47128448/