iOS 13 中的属性字符串问题

Question

我正在使用以下扩展将 HTML 字符串转换为属性字符串，以呈现我正在使用 UILabel 的属性字符串。字体系列是 system-regular，iPhone/iPad 的点数为 15/18。在上面的图片中，Description 是标题，属性字符串是值。

extension NSAttributedString {

    internal convenience init?(html: String, font : UIFont) {

        let modifiedFont = String(format:"<span style=\"font-family: '-apple-system', '\(font.fontName)'; font-size: \(font.pointSize)\">%@</span>", html)

        guard let data = modifiedFont.data(using: String.Encoding.utf16, allowLossyConversion: false) else {
            return nil
        }

        guard let attributedString = try? NSMutableAttributedString(data: data, options: [NSAttributedString.DocumentReadingOptionKey.documentType: NSAttributedString.DocumentType.html], documentAttributes: nil) else {
            return nil
        }

        self.init(attributedString: attributedString)
    }
}

上述扩展中变量的控制台打印

(lldb) po html
"<p><font size=\"2\">Pack Size: 2.5 Gal x 2</font></p><p><font size=\"2\">Gallons per case / bucket / barrel:</font></p><p><font size=\"2\">1 Case – 5.0 Gal<br>&nbsp;2 Cases – 10.0 Gal<br>&nbsp;3 Cases – 15.0 Gal</font></p>"

(lldb) po font
<UICTFont: 0x7ffbe4b03a20> font-family: ".SFUI-Regular"; font-weight: normal; font-style: normal; font-size: 15.00pt


(lldb) po modifiedFont
"<span style=\"font-family: \'-apple-system\', \'.SFUI-Regular\'; font-size: 15.0\"><p><font size=\"2\">Pack Size: 2.5 Gal x 2</font></p><p><font size=\"2\">Gallons per case / bucket / barrel:</font></p><p><font size=\"2\">1 Case – 5.0 Gal<br>&nbsp;2 Cases – 10.0 Gal<br>&nbsp;3 Cases – 15.0 Gal</font></p></span>"

我正在呼叫如下分机

self.lblValueDescription.attributedText = NSAttributedString(html: data.descriptionField,
                                                                     font: self.lblValueDescription.font)

输出在iOS12

输出在iOS13

问题：

字体大小与 iOS12
iOS13 有一些具有相同 html 字符串的外来字符。

Answer 1

这有点 encode/decode 不匹配的味道。您明确指定 utf16 用于数据编码。但是，由于 this，您的编码可能存在冲突。这也可以解释乱码和 iOS 12 vs 13 问题。

Answer 2

试试这个解决方案，它对我这边的 ios 12 和 13 都有效，可能对你有帮助。

extension String
{
 func htmlAttributed(family: String?, size: CGFloat, colorHex: String) -> NSAttributedString?
  {
    do {
        let htmlCSSString = "<style>" +
            "html *" +
            "{" +
            "font-size: \(size)pt !important;" +
             "color: " + "\(colorHex)" + " !important;" +
            "font-family: \(family ?? "Helvetica"), Helvetica !important;" +
        "}</style> \(self)"

        guard let data = htmlCSSString.data(using: String.Encoding.utf8) else {
            return nil
        }

        return try NSAttributedString(data: data,
                                      options: [.documentType: NSAttributedString.DocumentType.html,
                                                .characterEncoding: String.Encoding.utf8.rawValue],
                                      documentAttributes: nil)
    } catch {
        print("error: ", error)
        return nil
    }
  }
}

并通过此行设置文本

 self.lblValueDescription.attributedText = yourHtmlString.htmlAttributed(family: "Roboto-Regular", size: 11,colorHex: "#000000")!

Edit:

查看我在下面所做的答案后更改了

 let modifiedFont = String(format:"<style>html *{font-family: '-apple-system', '\(font.fontName)' !important; font-size: \(font.pointSize) !important}</style>%@", html)

用样式块修改样式标签
!important 添加标志以强制应用样式。

iOS 13 中的属性字符串问题

attributed string issue in iOS 13

nsattributedstring

ios

swift