NSFontAttributeName未应用于NSAttributedString

问题描述

我目前正在使用此提供的此扩展程序，将html转换为的UITextView 。一切都很完美，但由于某些奇怪的原因， NSFontAttributeName 在此过程中未应用于字符串。我在这里做错了吗？ （或者我应该在重新使用归属的html解析字符串后应用 NSAttributedString ？如果是这样，是否可以将属性应用于 NSAttributeString ？）。

I'm currently using this extension provided by this answer to convert html to strings within a UITextView. Everything works perfectly but for some strange reason the NSFontAttributeName is not applied to the string during the process. Is there something I'm doing wrong here? (or should I apply the NSAttributedString after reeving the attributed html parsed string? If so, is it possible to apply an attribute to an NSAttributeString? ).

PS。使用 html2String 时字体大小不会改变，但html中的链接会被 UITextView

PS. Font size is not change when using html2String but the links within the html is are longer recognized by the UITextView

extension String {

    var html2AttributedString: NSAttributedString? {
        guard
            let data = dataUsingEncoding(NSUTF8StringEncoding)
            else { return nil }
        do {
            return try NSAttributedString(data: data, options: [NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType,NSCharacterEncodingDocumentAttribute:NSUTF8StringEncoding, NSFontAttributeName : UIFont.systemFontOfSize(17.0)], documentAttributes: nil)
        } catch let error as NSError {
            print(error.localizedDescription)
            return  nil
        }
    }
    var html2String: String {
        return html2AttributedString?.string ?? ""
    }
}
cell.desc.attributedText  = apiData[currentIndex].description!.html2AttributedString //Font attribute not recognized
cell.desc.text  = apiData[currentIndex].description!.html2String //Font recognized by links no longer recognized

推荐答案

我不确定为什么（可能是因为有一个范围）但是如果你首先创建一个NSMutableAttributedString然后添加UIFont属性它会起作用：

I'm not sure why (probably because of having a range) but it works if you first create an NSMutableAttributedString and then you add the UIFont attributes:

extension String {

    var html2AttributedString: NSMutableAttributedString? {
        guard
            let data = dataUsingEncoding(NSUTF8StringEncoding)
            else { return nil }
        do {
            let attrStr = try NSMutableAttributedString(data: data, options: [NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType,NSCharacterEncodingDocumentAttribute:NSUTF8StringEncoding], documentAttributes: nil)
            attrStr.addAttributes([NSFontAttributeName: UIFont.systemFontOfSize(17.0)], range: NSRange(location: 0, length: attrStr.length))
            return attrStr
        } catch let error as NSError {
            print(error.localizedDescription)
            return  nil
        }
    }
    var html2String: String {
        return html2AttributedString?.string ?? ""
    }
}

这篇关于NSFontAttributeName未应用于NSAttributedString的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！