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
我强烈建议使用自动检测文本中的url并将其转换为链接的库。 试一试:
TTTAttributedLabel (pod) ZSWTappableLabel (under).
两者都得到了麻省理工学院的许可。
其他回答
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()
}
我找到了另一个解决方案:
我找到了一种方法来检测你从互联网上找到的html文本链接,你把它转换成nsattributeString:
func htmlAttributedString(fontSize: CGFloat = 17.0) -> NSAttributedString? {
let fontName = UIFont.systemFont(ofSize: fontSize).fontName
let string = self.appending(String(format: "<style>body{font-family: '%@'; font-size:%fpx;}</style>", fontName, fontSize))
guard let data = string.data(using: String.Encoding.utf16, allowLossyConversion: false) else { return nil }
guard let html = try? NSMutableAttributedString (
data: data,
options: [NSAttributedString.DocumentReadingOptionKey.documentType: NSAttributedString.DocumentType.html],
documentAttributes: nil) else { return nil }
return html
}
我的方法允许您检测超链接,而无需指定它们。
first you create an extension of the tapgesturerecognizer : extension UITapGestureRecognizer { func didTapAttributedTextInLabel(label: UILabel, inRange targetRange: NSRange) -> Bool { guard let attrString = label.attributedText else { return false } let layoutManager = NSLayoutManager() let textContainer = NSTextContainer(size: .zero) let textStorage = NSTextStorage(attributedString: attrString) layoutManager.addTextContainer(textContainer) textStorage.addLayoutManager(layoutManager) textContainer.lineFragmentPadding = 0 textContainer.lineBreakMode = label.lineBreakMode textContainer.maximumNumberOfLines = label.numberOfLines let labelSize = label.bounds.size textContainer.size = labelSize 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) } }
然后在你的视图控制器中,你创建了一个url和范围列表来存储属性文本包含的所有链接和范围:
var listurl : [String] = []
var listURLRange : [NSRange] = []
找到URL和URLRange,你可以使用:
fun findLinksAndRange(attributeString : NSAttributeString){
notification.enumerateAttribute(NSAttributedStringKey.link , in: NSMakeRange(0, notification.length), options: [.longestEffectiveRangeNotRequired]) { value, range, isStop in
if let value = value {
print("\(value) found at \(range.location)")
let stringValue = "\(value)"
listurl.append(stringValue)
listURLRange.append(range)
}
}
westlandNotifcationLabel.addGestureRecognizer(UITapGestureRecognizer(target : self, action: #selector(handleTapOnLabel(_:))))
}
然后你实现了手柄tap:
@objc func handleTapOnLabel(_ recognizer: UITapGestureRecognizer) {
for index in 0..<listURLRange.count{
if recognizer.didTapAttributedTextInLabel(label: westlandNotifcationLabel, inRange: listURLRange[index]) {
goToWebsite(url : listurl[index])
}
}
}
func goToWebsite(url : String){
if let websiteUrl = URL(string: url){
if #available(iOS 10, *) {
UIApplication.shared.open(websiteUrl, options: [:],
completionHandler: {
(success) in
print("Open \(websiteUrl): \(success)")
})
} else {
let success = UIApplication.shared.openURL(websiteUrl)
print("Open \(websiteUrl): \(success)")
}
}
}
开始了!
我希望这个解决方案能帮助你,就像它帮助我一样。
一般来说,如果我们想在UILabel显示的文本中有一个可点击的链接,我们需要解决两个独立的任务:
更改部分文本的外观,使其看起来像链接 检测和处理链接上的触摸(打开URL是一个特殊情况)
第一个很简单。从ios6开始,UILabel支持显示带属性的字符串。你所需要做的就是创建并配置一个NSMutableAttributedString实例:
NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:@"String with a link" attributes:nil];
NSRange linkRange = NSMakeRange(14, 4); // for the word "link" in the string above
NSDictionary *linkAttributes = @{ NSForegroundColorAttributeName : [UIColor colorWithRed:0.05 green:0.4 blue:0.65 alpha:1.0],
NSUnderlineStyleAttributeName : @(NSUnderlineStyleSingle) };
[attributedString setAttributes:linkAttributes range:linkRange];
// Assign attributedText to UILabel
label.attributedText = attributedString;
就是这样!上面的代码使UILabel显示带有链接的String
现在我们应该检测这个链接上的触摸。其思想是捕获UILabel中的所有点击,并确定点击的位置是否足够接近链接。为了捕捉触摸,我们可以在标签中添加点击手势识别器。确保为标签启用userInteraction,默认情况下是关闭的:
label.userInteractionEnabled = YES;
[label addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTapOnLabel:)]];
现在最复杂的事情是:找出点击是否在显示链接的地方,而不是在标签的任何其他部分。如果我们有单行UILabel,这个任务可以通过硬编码链接显示的区域边界来相对容易地解决,但是让我们更优雅地解决这个问题,对于一般情况-多行UILabel,而不需要对链接布局有初步的了解。
其中一种方法是使用iOS 7中引入的Text Kit API功能:
// Create instances of NSLayoutManager, NSTextContainer and NSTextStorage
NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init];
NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:CGSizeZero];
NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:attributedString];
// Configure layoutManager and textStorage
[layoutManager addTextContainer:textContainer];
[textStorage addLayoutManager:layoutManager];
// Configure textContainer
textContainer.lineFragmentPadding = 0.0;
textContainer.lineBreakMode = label.lineBreakMode;
textContainer.maximumNumberOfLines = label.numberOfLines;
将创建和配置的NSLayoutManager, NSTextContainer和NSTextStorage实例保存在类的属性中(很可能是UIViewController的后代)-我们将在其他方法中需要它们。
现在,每当标签改变它的框架,更新textContainer的大小:
- (void)viewDidLayoutSubviews
{
[super viewDidLayoutSubviews];
self.textContainer.size = self.label.bounds.size;
}
最后,检测点击是否恰好在链接上:
- (void)handleTapOnLabel:(UITapGestureRecognizer *)tapGesture
{
CGPoint locationOfTouchInLabel = [tapGesture locationInView:tapGesture.view];
CGSize labelSize = tapGesture.view.bounds.size;
CGRect textBoundingBox = [self.layoutManager usedRectForTextContainer:self.textContainer];
CGPoint textContainerOffset = CGPointMake((labelSize.width - textBoundingBox.size.width) * 0.5 - textBoundingBox.origin.x,
(labelSize.height - textBoundingBox.size.height) * 0.5 - textBoundingBox.origin.y);
CGPoint locationOfTouchInTextContainer = CGPointMake(locationOfTouchInLabel.x - textContainerOffset.x,
locationOfTouchInLabel.y - textContainerOffset.y);
NSInteger indexOfCharacter = [self.layoutManager characterIndexForPoint:locationOfTouchInTextContainer
inTextContainer:self.textContainer
fractionOfDistanceBetweenInsertionPoints:nil];
NSRange linkRange = NSMakeRange(14, 4); // it's better to save the range somewhere when it was originally used for marking link in attributed string
if (NSLocationInRange(indexOfCharacter, linkRange)) {
// Open an URL, or handle the tap on the link in any other way
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"https://stackoverflow.com/"]];
}
}
这里是一个Swift实现,它是尽可能少的,还包括触摸反馈。警告:
你必须在NSAttributedStrings中设置字体 你只能使用NSAttributedStrings! 你必须确保你的链接不能自动换行(使用不间断的空格:"\u{a0}") 设置文本后,不能更改lineBreakMode或numberolines 通过添加带有.link键的属性来创建链接
.
public class LinkLabel: UILabel {
private var storage: NSTextStorage?
private let textContainer = NSTextContainer()
private let layoutManager = NSLayoutManager()
private var selectedBackgroundView = UIView()
override init(frame: CGRect) {
super.init(frame: frame)
textContainer.lineFragmentPadding = 0
layoutManager.addTextContainer(textContainer)
textContainer.layoutManager = layoutManager
isUserInteractionEnabled = true
selectedBackgroundView.isHidden = true
selectedBackgroundView.backgroundColor = UIColor(white: 0, alpha: 0.3333)
selectedBackgroundView.layer.cornerRadius = 4
addSubview(selectedBackgroundView)
}
public required convenience init(coder: NSCoder) {
self.init(frame: .zero)
}
public override func layoutSubviews() {
super.layoutSubviews()
textContainer.size = frame.size
}
public override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesBegan(touches, with: event)
setLink(for: touches)
}
public override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesMoved(touches, with: event)
setLink(for: touches)
}
private func setLink(for touches: Set<UITouch>) {
if let pt = touches.first?.location(in: self), let (characterRange, _) = link(at: pt) {
let glyphRange = layoutManager.glyphRange(forCharacterRange: characterRange, actualCharacterRange: nil)
selectedBackgroundView.frame = layoutManager.boundingRect(forGlyphRange: glyphRange, in: textContainer).insetBy(dx: -3, dy: -3)
selectedBackgroundView.isHidden = false
} else {
selectedBackgroundView.isHidden = true
}
}
public override func touchesCancelled(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesCancelled(touches, with: event)
selectedBackgroundView.isHidden = true
}
public override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesEnded(touches, with: event)
selectedBackgroundView.isHidden = true
if let pt = touches.first?.location(in: self), let (_, url) = link(at: pt) {
UIApplication.shared.open(url)
}
}
private func link(at point: CGPoint) -> (NSRange, URL)? {
let touchedGlyph = layoutManager.glyphIndex(for: point, in: textContainer)
let touchedChar = layoutManager.characterIndexForGlyph(at: touchedGlyph)
var range = NSRange()
let attrs = attributedText!.attributes(at: touchedChar, effectiveRange: &range)
if let urlstr = attrs[.link] as? String {
return (range, URL(string: urlstr)!)
} else {
return nil
}
}
public override var attributedText: NSAttributedString? {
didSet {
textContainer.maximumNumberOfLines = numberOfLines
textContainer.lineBreakMode = lineBreakMode
if let txt = attributedText {
storage = NSTextStorage(attributedString: txt)
storage!.addLayoutManager(layoutManager)
layoutManager.textStorage = storage
textContainer.size = frame.size
}
}
}
}
就像在前面的回答中报告的那样,UITextView能够处理链接上的触摸。这可以通过将文本的其他部分作为链接来轻松扩展。AttributedTextView库是一个UITextView子类,它使得处理这些非常容易。更多信息请参见:https://github.com/evermeer/AttributedTextView
你可以让文本的任何部分像这样交互(其中textView1是一个UITextView IBOutlet):
textView1.attributer =
"1. ".red
.append("This is the first test. ").green
.append("Click on ").black
.append("evict.nl").makeInteract { _ in
UIApplication.shared.open(URL(string: "http://evict.nl")!, options: [:], completionHandler: { completed in })
}.underline
.append(" for testing links. ").black
.append("Next test").underline.makeInteract { _ in
print("NEXT")
}
.all.font(UIFont(name: "SourceSansPro-Regular", size: 16))
.setLinkColor(UIColor.purple)
为了处理标签和提及,你可以使用这样的代码:
textView1.attributer = "@test: What #hashtags do we have in @evermeer #AtributedTextView library"
.matchHashtags.underline
.matchMentions
.makeInteract { link in
UIApplication.shared.open(URL(string: "https://twitter.com\(link.replacingOccurrences(of: "@", with: ""))")!, options: [:], completionHandler: { completed in })
}
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