许多应用程序都有文本,文本中是圆角矩形的web超链接,当我点击它们时,UIWebView就会打开。让我困惑的是,他们经常有自定义链接,例如,如果单词以#开头,它也是可点击的,应用程序通过打开另一个视图来响应。我该怎么做呢?是否可以用UILabel或者我需要UITextView或者其他什么?


当前回答

我正在扩展@NAlexN原始的详细解决方案,与@zekel优秀的UITapGestureRecognizer扩展,并在Swift中提供。

Extending UITapGestureRecognizer

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 = 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 = 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)
    }

}

使用

设置UIGestureRecognizer发送动作到tapLabel:,你可以检测目标范围是否在myLabel上被点击。

@IBAction func tapLabel(gesture: UITapGestureRecognizer) {
    if gesture.didTapAttributedTextInLabel(myLabel, inRange: targetRange1) {
        print("Tapped targetRange1")
    } else if gesture.didTapAttributedTextInLabel(myLabel, inRange: targetRange2) {
        print("Tapped targetRange2")
    } else {
        print("Tapped none")
    }
}

重要提示:UILabel换行模式必须设置为按word/char换行。以某种方式,只有当换行模式为其他模式时,NSTextContainer才会假定文本为单行。

其他回答

我正在扩展@NAlexN原始的详细解决方案,与@zekel优秀的UITapGestureRecognizer扩展,并在Swift中提供。

Extending UITapGestureRecognizer

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 = 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 = 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)
    }

}

使用

设置UIGestureRecognizer发送动作到tapLabel:,你可以检测目标范围是否在myLabel上被点击。

@IBAction func tapLabel(gesture: UITapGestureRecognizer) {
    if gesture.didTapAttributedTextInLabel(myLabel, inRange: targetRange1) {
        print("Tapped targetRange1")
    } else if gesture.didTapAttributedTextInLabel(myLabel, inRange: targetRange2) {
        print("Tapped targetRange2")
    } else {
        print("Tapped none")
    }
}

重要提示:UILabel换行模式必须设置为按word/char换行。以某种方式,只有当换行模式为其他模式时,NSTextContainer才会假定文本为单行。

在Swift 3中工作,将整个代码粘贴在这里

    //****Make sure the textview 'Selectable' = checked, and 'Editable = Unchecked'

import UIKit

class ViewController: UIViewController, UITextViewDelegate {

    @IBOutlet var theNewTextView: UITextView!
    override func viewDidLoad() {
        super.viewDidLoad()

        //****textview = Selectable = checked, and Editable = Unchecked

        theNewTextView.delegate = self

        let theString = NSMutableAttributedString(string: "Agree to Terms")
        let theRange = theString.mutableString.range(of: "Terms")

        theString.addAttribute(NSLinkAttributeName, value: "ContactUs://", range: theRange)

        let theAttribute = [NSForegroundColorAttributeName: UIColor.blue, NSUnderlineStyleAttributeName: NSUnderlineStyle.styleSingle.rawValue] as [String : Any]

        theNewTextView.linkTextAttributes = theAttribute

     theNewTextView.attributedText = theString             

theString.setAttributes(theAttribute, range: theRange)

    }

    func textView(_ textView: UITextView, shouldInteractWith URL: URL, in characterRange: NSRange, interaction: UITextItemInteraction) -> Bool {

        if (URL.scheme?.hasPrefix("ContactUs://"))! {

            return false //interaction not allowed
        }

        //*** Set storyboard id same as VC name
        self.navigationController!.pushViewController((self.storyboard?.instantiateViewController(withIdentifier: "TheLastViewController"))! as UIViewController, animated: true)

        return true
    }

}

我扩展了@samwize的答案来处理多行UILabel,并给出了一个使用UIButton的例子

extension UITapGestureRecognizer {

    func didTapAttributedTextInButton(button: UIButton, inRange targetRange: NSRange) -> Bool {
        guard let label = button.titleLabel else { return false }
        return didTapAttributedTextInLabel(label, inRange: targetRange)
    }

    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.locationInView(label)
        let textBoundingBox = layoutManager.usedRectForTextContainer(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 locationOfTouchInTextContainer = CGPointMake((locationOfTouchInLabel.x - textContainerOffset.x),
                                                         0 );
        // Adjust for multiple lines of text
        let lineModifier = Int(ceil(locationOfTouchInLabel.y / label.font.lineHeight)) - 1
        let rightMostFirstLinePoint = CGPointMake(labelSize.width, 0)
        let charsPerLine = layoutManager.characterIndexForPoint(rightMostFirstLinePoint, inTextContainer: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)

        let indexOfCharacter = layoutManager.characterIndexForPoint(locationOfTouchInTextContainer, inTextContainer: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
        let adjustedRange = indexOfCharacter + (lineModifier * charsPerLine)

        return NSLocationInRange(adjustedRange, targetRange)
    }

}

这个通用方法也可以!

func didTapAttributedTextInLabel(gesture: UITapGestureRecognizer, inRange targetRange: NSRange) -> Bool {

        let layoutManager = NSLayoutManager()
        let textContainer = NSTextContainer(size: CGSize.zero)
        guard let strAttributedText = self.attributedText else {
            return false
        }

        let textStorage = NSTextStorage(attributedString: strAttributedText)

        // Configure layoutManager and textStorage
        layoutManager.addTextContainer(textContainer)
        textStorage.addLayoutManager(layoutManager)

        // Configure textContainer
        textContainer.lineFragmentPadding = Constants.lineFragmentPadding
        textContainer.lineBreakMode = self.lineBreakMode
        textContainer.maximumNumberOfLines = self.numberOfLines
        let labelSize = self.bounds.size
        textContainer.size = CGSize(width: labelSize.width, height: CGFloat.greatestFiniteMagnitude)

        // Find the tapped character location and compare it to the specified range
        let locationOfTouchInLabel = gesture.location(in: self)

        let xCordLocationOfTouchInTextContainer = locationOfTouchInLabel.x
        let yCordLocationOfTouchInTextContainer = locationOfTouchInLabel.y
        let locOfTouch = CGPoint(x: xCordLocationOfTouchInTextContainer ,
                                 y: yCordLocationOfTouchInTextContainer)

        let indexOfCharacter = layoutManager.characterIndex(for: locOfTouch, in: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)

        guard let strLabel = text else {
            return false
        }

        let charCountOfLabel = strLabel.count

        if indexOfCharacter < (charCountOfLabel - 1) {
            return NSLocationInRange(indexOfCharacter, targetRange)
        } else {
            return false
        }
    }

你可以用

let text = yourLabel.text
let termsRange = (text as NSString).range(of: fullString)
if yourLabel.didTapAttributedTextInLabel(gesture: UITapGestureRecognizer, inRange: termsRange) {
            showCorrespondingViewController()
        }

标签# Swift2.0

我从- excellent - @NAlexN的回答中获得灵感,我决定自己写一个UILabel的包装器。 我还尝试了TTTAttributedLabel,但我不能使它工作。

希望你能欣赏这段代码,欢迎任何建议!

import Foundation

@objc protocol TappableLabelDelegate {
    optional func tappableLabel(tabbableLabel: TappableLabel, didTapUrl: NSURL, atRange: NSRange)
}

/// Represent a label with attributed text inside.
/// We can add a correspondence between a range of the attributed string an a link (URL)
/// By default, link will be open on the external browser @see 'openLinkOnExternalBrowser'

class TappableLabel: UILabel {

    // MARK: - Public properties -

    var links: NSMutableDictionary = [:]
    var openLinkOnExternalBrowser = true
    var delegate: TappableLabelDelegate?

    // MARK: - Constructors -

    override func awakeFromNib() {
        super.awakeFromNib()
        self.enableInteraction()
    }

    override init(frame: CGRect) {
        super.init(frame: frame)
        self.enableInteraction()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }

    private func enableInteraction() {
        self.userInteractionEnabled = true
        self.addGestureRecognizer(UITapGestureRecognizer(target: self, action: Selector("didTapOnLabel:")))
    }

    // MARK: - Public methods -

    /**
    Add correspondence between a range and a link.

    - parameter url:   url.
    - parameter range: range on which couple url.
    */
    func addLink(url url: String, atRange range: NSRange) {
        self.links[url] = range
    }

    // MARK: - Public properties -

    /**
    Action rised on user interaction on label.

    - parameter tapGesture: gesture.
    */
    func didTapOnLabel(tapGesture: UITapGestureRecognizer) {
        let labelSize = self.bounds.size;

        let layoutManager = NSLayoutManager()
        let textContainer = NSTextContainer(size: CGSizeZero)
        let textStorage = NSTextStorage(attributedString: self.attributedText!)

        // configure textContainer for the label
        textContainer.lineFragmentPadding = 0
        textContainer.lineBreakMode = self.lineBreakMode
        textContainer.maximumNumberOfLines = self.numberOfLines
        textContainer.size = labelSize;

        // configure layoutManager and textStorage
        layoutManager.addTextContainer(textContainer)
        textStorage.addLayoutManager(layoutManager)

        // find the tapped character location and compare it to the specified range
        let locationOfTouchInLabel = tapGesture.locationInView(self)

        let textBoundingBox = layoutManager.usedRectForTextContainer(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 locationOfTouchInTextContainer = CGPointMake(locationOfTouchInLabel.x - textContainerOffset.x,
            locationOfTouchInLabel.y - textContainerOffset.y)
        let indexOfCharacter = layoutManager.characterIndexForPoint(locationOfTouchInTextContainer,
            inTextContainer:textContainer,
            fractionOfDistanceBetweenInsertionPoints: nil)

        for (url, value) in self.links {
            if let range = value as? NSRange {
                if NSLocationInRange(indexOfCharacter, range) {
                    let url = NSURL(string: url as! String)!
                    if self.openLinkOnExternalBrowser {
                        UIApplication.sharedApplication().openURL(url)
                    }
                    self.delegate?.tappableLabel?(self, didTapUrl: url, atRange: range)
                }
            }
        }
    }

}