Question

我正在尝试创建一个属性字符串，其中在字符串的末尾附加了一个链接：

func addMoreAndLessFunctionality (textView:UITextView){
        if textView.text.characters.count >= 120
        {
            let lengthOfString = 255
            var abc : String =  (somelongStringInitiallyAvailable as NSString).substringWithRange(NSRange(location: 0, length: lengthOfString))
            abc += " ...More"
            textView.text = abc
            let attribs = [NSForegroundColorAttributeName: StyleKit.appDescriptionColor, NSFontAttributeName: StyleKit.appDescriptionFont]
            let attributedString: NSMutableAttributedString = NSMutableAttributedString(string: abc, attributes: attribs)


            attributedString.addAttribute(NSLinkAttributeName, value: " ...More", range: NSRange(location:255, length: 8))

          textView.attributedText = attributedString
            textView.textContainer.maximumNumberOfLines = 3;

        }
}

我想在这里尝试实现的是，如果文本视图中的字符文本超过255，则应显示＆＃34; ...更多＆＃34;链接在文本视图中，可点击，点按我已经能够获得代表＆＃34; shouldInteractWithUrl＆＃34;调用，我在文本视图中增加行数，并将链接文本更改为＆＃34; ... Less＆＃34;。点击Less I再次调用相同的方法，以便它可以再次截断。：

    func textView(textView: UITextView, shouldInteractWithURL URL: NSURL, inRange characterRange: NSRange) -> Bool
{
    print("textview should interact with URl")

    let textTapped = textView.text[textView.text.startIndex.advancedBy(characterRange.location)..<textView.text.endIndex]

    if textTapped == " ...More"{

        var abc : String =  (self.contentDetailItemManaged?.whatsnewDesc)!
        abc += " ...Less"
        textView.textContainer.maximumNumberOfLines = 0
        let attribs = [NSForegroundColorAttributeName: StyleKit.appDescriptionColor, NSFontAttributeName: StyleKit.appDescriptionFont]
        let attributedString: NSMutableAttributedString = NSMutableAttributedString(string: abc, attributes: attribs)
        attributedString.addAttribute(NSLinkAttributeName, value: " ...Less", range: NSRange(location:abc.characters.count-8 , length: 8))

        textView.attributedText = attributedString


    }
    else if textTapped == " ...Less"{

        textView.attributedText = nil
        textView.text = somelongStringInitiallyAvailable
        self.addMoreAndLessFunctionality(textView)
    }

    return true
}

现在问题是，当第一次调用第一个方法时（在我设置了textview文本之后调用它），它工作正常，但点击＆＃34; ...更多＆＃34 ;, textview正常扩展，＆＃34; ...更多＆＃34;改变为＆＃34; ...少＆＃34 ;.当＆＃34; ...较少＆＃34;被点击，它崩溃并发生异常：

[NSConcreteTextStorage attribute:atIndex:effectiveRange:]: Range or index out of bounds'

任何帮助将不胜感激。（也是字符串＆＃34; ...更多＆＃34;开头有一个空格，所以共有8个字符，我可能在输入代码时错过了这个空格）

谢谢：）

Answer 1

.then(course => {/* check if the course is null and then throws an error */} )在return false

[NSConcreteTextStorage属性：atIndex：effectiveRange：]：NSMutableAttributedString

1 个答案: