我有一个UITextView,应该接收HTML压缩的NSAttributesString。最终结果是带有链接的自定义下划线的黑色文本。我在范围上崩溃了。
由于未捕获的异常“ NSRangeException”而终止应用程序,原因:“ NSMutableRLEArray objectAtIndex:effectiveRange ::越界”
代码如下:
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let text = "random text <a href='http://www.google.com'>http://www.google.com </a> more random text"
let storage = NSTextStorage()
let layout = UnderlineLayout()
storage.addLayoutManager(layout)
let container = NSTextContainer()
layout.addTextContainer(container)
let textView = UITextView(frame: CGRect(x: 30, y: 380, width: 300, height: 200), textContainer: container)
textView.isUserInteractionEnabled = true
textView.isEditable = false
textView.textContainerInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
textView.text = text
// textView.attributedText = htmlStyleAttributeText(text: text)
textView.backgroundColor = UIColor.white
textView.textColor = UIColor.black
let underLineColor: UIColor = UIColor(red: 245/255, green: 190/255, blue: 166/255, alpha: 1)
let attributes = [NSAttributedString.Key.underlineStyle.rawValue: 0x15,
NSAttributedString.Key.underlineColor: underLineColor,
NSAttributedString.Key.font: UIFont.systemFont(ofSize: 25),
NSAttributedString.Key.baselineOffset:0] as! [NSAttributedString.Key : Any]
let rg = NSRange(text.startIndex..., in: text)
storage.addAttributes(attributes, range: rg)
view.addSubview(textView)
}
public func htmlStyleAttributeText(text: String) -> NSMutableAttributedString? {
if let htmlData = text.data(using: .utf8) {
let options: [NSAttributedString.DocumentReadingOptionKey: Any] = [NSAttributedString.DocumentReadingOptionKey.documentType: NSAttributedString.DocumentType.html, NSAttributedString.DocumentReadingOptionKey.characterEncoding: String.Encoding.utf8.rawValue]
let attributedString = try? NSMutableAttributedString(data: htmlData, options: options, documentAttributes: nil)
return attributedString
}
return nil
}
}
import UIKit
class UnderlineLayout: NSLayoutManager {
override func drawUnderline(forGlyphRange glyphRange: NSRange, underlineType underlineVal: NSUnderlineStyle, baselineOffset: CGFloat, lineFragmentRect lineRect: CGRect, lineFragmentGlyphRange lineGlyphRange: NSRange, containerOrigin: CGPoint) {
if let container = textContainer(forGlyphAt: glyphRange.location, effectiveRange: nil) {
let boundingRect = self.boundingRect(forGlyphRange: glyphRange, in: container)
let offsetRect = boundingRect.offsetBy(dx: containerOrigin.x, dy: containerOrigin.y)
let left = offsetRect.minX
let bottom = offsetRect.maxY
let width = offsetRect.width
let path = UIBezierPath()
path.lineWidth = 4
path.move(to: CGPoint(x: left, y: bottom))
path.addLine(to: CGPoint(x: left + width, y: bottom))
path.stroke()
}
}
}
当我评论以下行时:textView.text = text
然后取消注释,所有崩溃:textView.attributedText = htmlStyleAttributeText(text: text)
答案 0 :(得分:1)
let rg = NSRange(text.startIndex..., in: text)
=>
let rg = NSRange(text.startIndex..., in: textView.attributedText!.string)
因为第一个返回{0,87},第二个返回{0,50}。正常,“ html标记”已被解释并从最终字符串中删除以显示。