点击UILabel的一部分文本

Tap on a part of text of UILabel(点击UILabel的一部分文本)

本文介绍了点击UILabel的一部分文本的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

我遇到一个问题,boundingRectForGlyphRange始终返回CGRect.zero";0.0,0.0,0.0,0.0";。 例如,我正在编码以触摸UILabel功能的一部分文本。我的文本第一部分是任何文本,第二部分是多读

我希望点击识别器仅在我触摸阅读更多内容时才起作用。如果我触及UILabel上的任何点,CGRectContainsPoint始终返回true,则该操作调用。

这里是我的代码:

override func viewDidLoad() {
        super.viewDidLoad()
        
        // The full string
        
        let firstPart:NSMutableAttributedString = NSMutableAttributedString(string: "Lorem ipsum dolor set amit ", attributes: [NSFontAttributeName: UIFont.systemFontOfSize(13)])
        firstPart.addAttribute(NSForegroundColorAttributeName, value: UIColor.blackColor(),
            range: NSRange(location: 0, length: firstPart.length))
        info.appendAttributedString(firstPart)
        
        // The "Read More" string that should be touchable
        let secondPart:NSMutableAttributedString = NSMutableAttributedString(string: "READ MORE", attributes: [NSFontAttributeName: UIFont.systemFontOfSize(14)])
        secondPart.addAttribute(NSForegroundColorAttributeName, value: UIColor.blackColor(),
            range: NSRange(location: 0, length: secondPart.length))
        info.appendAttributedString(secondPart)
        
        lblTest.attributedText = info
        
        // Store range of chars we want to detect touches for
        moreStringRange = NSMakeRange(firstPart.length, secondPart.length)
        print("moreStringRange(moreStringRange)")
        
        tapRec.addTarget(self, action: "didTap:")
        lblTest.addGestureRecognizer(tapRec)
        
    }


    func didTap(sender:AnyObject) {
        // Storage class stores the string, obviously
        let textStorage:NSTextStorage = NSTextStorage(attributedString: info)
        // The storage class owns a layout manager
        let layoutManager:NSLayoutManager = NSLayoutManager()
        textStorage.addLayoutManager(layoutManager)
        
        // Layout manager owns a container which basically
        // defines the bounds the text should be contained in
        let textContainer:NSTextContainer = NSTextContainer(size: lblTest.frame.size)
        textContainer.lineFragmentPadding = 0
        textContainer.lineBreakMode = lblTest.lineBreakMode
        
        // Begin computation of actual frame
        // Glyph is the final display representation
        var glyphRange = NSRange()
        // Extract the glyph range
        layoutManager.characterRangeForGlyphRange(moreStringRange!, actualGlyphRange: &glyphRange)
        
        // Compute the rect of glyph in the text container
        print("glyphRange(glyphRange)")
        print("textContainer(textContainer)")
        let glyphRect:CGRect = layoutManager.boundingRectForGlyphRange(glyphRange, inTextContainer: textContainer)
        
        // Final rect relative to the textLabel.
        print("(glyphRect)")
        
        // Now figure out if the touch point is inside our rect
        let touchPoint:CGPoint = tapRec.locationOfTouch(0, inView: lblTest)
        
        if CGRectContainsPoint(glyphRect, touchPoint) {
            print("User tapped on Read More. So show something more")
        }
    }
}

推荐答案

#SWIFT4.2 请在此处找到获取Label的特定文本action的解决方案。

  1. 标签声明

    @IBOutlet weak var lblTerms: UILabel!
    
  2. 将属性文本设置为标签

    let text = "Please agree for Terms & Conditions."
    lblTerms.text = text
    self.lblTerms.textColor =  UIColor.white
    let underlineAttriString = NSMutableAttributedString(string: text)
    let range1 = (text as NSString).range(of: "Terms & Conditions.")
         underlineAttriString.addAttribute(NSAttributedString.Key.underlineStyle, value: NSUnderlineStyle.single.rawValue, range: range1)
         underlineAttriString.addAttribute(NSAttributedString.Key.font, value: UIFont.init(name: Theme.Font.Regular, size: Theme.Font.size.lblSize)!, range: range1)
         underlineAttriString.addAttribute(NSAttributedString.Key.foregroundColor, value: Theme.color.primaryGreen, range: range1)
    lblTerms.attributedText = underlineAttriString
    lblTerms.isUserInteractionEnabled = true
    lblTerms.addGestureRecognizer(UITapGestureRecognizer(target:self, action: #selector(tapLabel(gesture:))))
    

如上图所示。

  1. tapLabel操作方法添加到控制器

    @IBAction func tapLabel(gesture: UITapGestureRecognizer) {
    let termsRange = (text as NSString).range(of: "Terms & Conditions")
    // comment for now
    //let privacyRange = (text as NSString).range(of: "Privacy Policy")
    
    if gesture.didTapAttributedTextInLabel(label: lblTerms, inRange: termsRange) {
        print("Tapped terms")
    } else if gesture.didTapAttributedTextInLabel(label: lblTerms, inRange: privacyRange) {
        print("Tapped privacy") 
    } else {                
        print("Tapped none")
    }
    }
    
  2. 添加UITapGestureRecognizer扩展

    extension UITapGestureRecognizer {
    
        func didTapAttributedTextInLabel(label: UILabel, inRange targetRange: NSRange) -> Bool {
            // Create instances of NSLayoutManager, NSTextContainer and NSTextStorage
            let layoutManager = NSLayoutManager()
            let textContainer = NSTextContainer(size: CGSize.zero)
            let textStorage = NSTextStorage(attributedString: label.attributedText!)
    
            // Configure layoutManager and textStorage
            layoutManager.addTextContainer(textContainer)
            textStorage.addLayoutManager(layoutManager)
    
            // Configure textContainer
            textContainer.lineFragmentPadding = 0.0
            textContainer.lineBreakMode = label.lineBreakMode
            textContainer.maximumNumberOfLines = label.numberOfLines
            let labelSize = label.bounds.size
            textContainer.size = labelSize
    
            // Find the tapped character location and compare it to the specified range
            let locationOfTouchInLabel = self.location(in: label)
            let textBoundingBox = layoutManager.usedRect(for: textContainer)
            //let textContainerOffset = CGPointMake((labelSize.width - textBoundingBox.size.width) * 0.5 - textBoundingBox.origin.x,
            //(labelSize.height - textBoundingBox.size.height) * 0.5 - textBoundingBox.origin.y);
            let textContainerOffset = CGPoint(x: (labelSize.width - textBoundingBox.size.width) * 0.5 - textBoundingBox.origin.x, y: (labelSize.height - textBoundingBox.size.height) * 0.5 - textBoundingBox.origin.y)
    
            //let locationOfTouchInTextContainer = CGPointMake(locationOfTouchInLabel.x - textContainerOffset.x,
            // locationOfTouchInLabel.y - textContainerOffset.y);
            let locationOfTouchInTextContainer = CGPoint(x: locationOfTouchInLabel.x - textContainerOffset.x, y: locationOfTouchInLabel.y - textContainerOffset.y)
            let indexOfCharacter = layoutManager.characterIndex(for: locationOfTouchInTextContainer, in: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
            return NSLocationInRange(indexOfCharacter, targetRange)
        }
    }
    

确保做到:

lblTerms.isUserInteractionEnabled = true

这篇关于点击UILabel的一部分文本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编程学习网!

本文标题为:点击UILabel的一部分文本

基础教程推荐