如何在Swift 3中仅针对UILabel的特定范围设置轻击手势
问题描述：
我将attributed string设置为UILabel，而multiple underlines，colors如下图所示
I have an attributed string set to UILabel with multiple underlines , colors like below image
我知道如何为整个标签设置轻敲手势(启用user interaction)，下面是我的代码，这是我所做的工作，包括设置underline和设置multiple ranges.
and I know How to setup a tap gesture for whole label (with enabling user interaction) and below is my code for what I have done including setting up underline and setting up font colors for multiple ranges.
import UIKit
class ViewController: UIViewController {
@IBOutlet weak var mylabel: UILabel!
var theString = "I have agree with the terms and conditions and privacy policy"
override func viewDidLoad() {
super.viewDidLoad()
mylabel.text = theString
let tap = UITapGestureRecognizer(target: self, action: #selector(ViewController.printme))
mylabel.addGestureRecognizer(tap)
setUnderline(theText: theString)
// Do any additional setup after loading the view, typically from a nib.
}
func printme() {
print("print this")
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func setUnderline(theText : String) {
//set up underline
let textRange1 = NSMakeRange(22, 19)
let textRange2 = NSMakeRange(47, (theText.characters.count-47))
let attributedText = NSMutableAttributedString(string : theText)
attributedText.addAttribute(NSUnderlineStyleAttributeName, value: NSUnderlineStyle.styleSingle.rawValue, range: textRange1)
attributedText.addAttribute(NSUnderlineStyleAttributeName, value: NSUnderlineStyle.styleSingle.rawValue, range: textRange2)
//setup colors
attributedText.addAttribute(NSForegroundColorAttributeName, value: UIColor.red, range: NSRange(location: 22,length: 20))
attributedText.addAttribute(NSForegroundColorAttributeName, value: UIColor.red, range: NSRange(location: 47,length: (theText.characters.count-47)))
mylabel.attributedText = attributedText
}
-
tap手势适用于whole label.我想要的是，当用户点击条款和条件"时会触发其他功能，而当用户点击隐私权政策"时会触发另一个功能.我怎样才能做到这一点. - The
tapgesture work forwhole label. what I want is when user tap on "terms and conditions" fire a different function and and when user tap on "privacy policy" fire another different function. how can I do that.
注意:我想触发两个不同的功能，一个用于条款和条件"轻按，另一个用于隐私权政策"轻按，但不希望 打开链接
Note : I want to fire two different functions one for "terms and conditions" tap, and other for "privacy policy" tap, and do not want to just open links
答
import UIKit
protocol SSGastureDelegate:NSObjectProtocol {
func callBack()
}
class SSUnderLineLabel: UILabel {
var tapGesture: UITapGestureRecognizer?
//Make weak refernece for SSGastureDelegate
weak var delegate:SSGastureDelegate?
required init(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)!
self.initialization()
}
override init(frame: CGRect) {
super.init(frame: frame)
self.initialization()
}
func initialization(){
let newsString: NSMutableAttributedString = NSMutableAttributedString(string: self.text!)
let textRange = NSString(string: self.text!)
let substringRange = textRange.range(of: "Terms and Conditions") // You can add here for own specific under line substring
newsString.addAttribute(NSUnderlineStyleAttributeName, value: NSUnderlineStyle.styleSingle.rawValue, range: substringRange)
// self.attributedText = newsString.copy() as? NSAttributedString
self.attributedText = newsString
self.tapGesture = UITapGestureRecognizer(target: self, action: #selector(tapResponse))
self.isUserInteractionEnabled = true
self.addGestureRecognizer(tapGesture!)
}
func tapResponse(recognizer: UITapGestureRecognizer) {
let text = (self.text)!
let termsRange = (text as NSString).range(of: "Terms and Conditions")
if (tapGesture?.didTapAttributedTextInLabel(label: self, inRange: termsRange))! {
print("Tapped terms conditions")
self.delegate?.callBack()
}
else {
print("Tapped none ")
}
}
}
//MARK:UITapGestureRecognizer Extension
//MARK:
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)
}
}*`enter code here`
**How to use it:**
Assign this class for your label and follow these steps:
Demo for use class:
ViewController.swift
//===============
class ViewController: UIViewController,SSGastureDelegate {
@IBOutlet var underlineLbl: SSUnderLineLabel!
override func viewDidLoad() {
super.viewDidLoad()
self.underlineLbl.delegate = self
}
//Implement Delegate Method
func callBack()
{
//Open a specific vc for underline tap are`enter code here`a.
let termsconditionsVC = storyboard?.instantiateViewController(withIdentifier: "TermsConditionsVC") as! TermsConditionsVC
self.present(termsconditions, animated: true, completion: nil)
}
}*