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
以下是基于@Luca Davanzo的回答,重写touchesBegan事件而不是轻触手势:
import UIKit
public protocol TapableLabelDelegate: NSObjectProtocol {
func tapableLabel(_ label: TapableLabel, didTapUrl url: String, atRange range: NSRange)
}
public class TapableLabel: UILabel {
private var links: [String: NSRange] = [:]
private(set) var layoutManager = NSLayoutManager()
private(set) var textContainer = NSTextContainer(size: CGSize.zero)
private(set) var textStorage = NSTextStorage() {
didSet {
textStorage.addLayoutManager(layoutManager)
}
}
public weak var delegate: TapableLabelDelegate?
public override var attributedText: NSAttributedString? {
didSet {
if let attributedText = attributedText {
textStorage = NSTextStorage(attributedString: attributedText)
} else {
textStorage = NSTextStorage()
links = [:]
}
}
}
public override var lineBreakMode: NSLineBreakMode {
didSet {
textContainer.lineBreakMode = lineBreakMode
}
}
public override var numberOfLines: Int {
didSet {
textContainer.maximumNumberOfLines = numberOfLines
}
}
public override init(frame: CGRect) {
super.init(frame: frame)
setup()
}
public required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setup()
}
public override func layoutSubviews() {
super.layoutSubviews()
textContainer.size = bounds.size
}
/// addLinks
///
/// - Parameters:
/// - text: text of link
/// - url: link url string
public func addLink(_ text: String, withURL url: String) {
guard let theText = attributedText?.string as? NSString else {
return
}
let range = theText.range(of: text)
guard range.location != NSNotFound else {
return
}
links[url] = range
}
private func setup() {
isUserInteractionEnabled = true
layoutManager.addTextContainer(textContainer)
textContainer.lineFragmentPadding = 0
textContainer.lineBreakMode = lineBreakMode
textContainer.maximumNumberOfLines = numberOfLines
}
public override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
guard let locationOfTouch = touches.first?.location(in: self) else {
return
}
textContainer.size = bounds.size
let indexOfCharacter = layoutManager.glyphIndex(for: locationOfTouch, in: textContainer)
for (urlString, range) in links {
if NSLocationInRange(indexOfCharacter, range), let url = URL(string: urlString) {
delegate?.tapableLabel(self, didTapUrl: urlString, atRange: range)
}
}
}}
其他回答
基于Charles Gamble的答案,这是我使用的(我删除了一些让我困惑并给我错误索引的行):
- (BOOL)didTapAttributedTextInLabel:(UILabel *)label inRange:(NSRange)targetRange TapGesture:(UIGestureRecognizer*) gesture{
NSParameterAssert(label != nil);
// create instances of NSLayoutManager, NSTextContainer and NSTextStorage
NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init];
NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:label.attributedText];
// configure layoutManager and textStorage
[textStorage addLayoutManager:layoutManager];
// configure textContainer for the label
NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:CGSizeMake(label.frame.size.width, label.frame.size.height)];
textContainer.lineFragmentPadding = 0.0;
textContainer.lineBreakMode = label.lineBreakMode;
textContainer.maximumNumberOfLines = label.numberOfLines;
// find the tapped character location and compare it to the specified range
CGPoint locationOfTouchInLabel = [gesture locationInView:label];
[layoutManager addTextContainer:textContainer]; //(move here, not sure it that matter that calling this line after textContainer is set
NSInteger indexOfCharacter = [layoutManager characterIndexForPoint:locationOfTouchInLabel
inTextContainer:textContainer
fractionOfDistanceBetweenInsertionPoints:nil];
if (NSLocationInRange(indexOfCharacter, targetRange)) {
return YES;
} else {
return NO;
}
}
UITextView支持OS3.0中的数据检测器,而UILabel不支持。
如果你在UITextView上启用了数据检测器,并且你的文本包含url、电话号码等,它们将以链接的形式出现。
修改了@timbroder代码,以正确处理swift4.2的多行
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: 0 );
// Adjust for multiple lines of text
let lineModifier = Int(ceil(locationOfTouchInLabel.y / label.font.lineHeight)) - 1
let rightMostFirstLinePoint = CGPoint(x: labelSize.width, y: 0)
let charsPerLine = layoutManager.characterIndex(for: rightMostFirstLinePoint, in: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
let indexOfCharacter = layoutManager.characterIndex(for: locationOfTouchInTextContainer, in: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
let adjustedRange = indexOfCharacter + (lineModifier * charsPerLine)
var newTargetRange = targetRange
if lineModifier > 0 {
newTargetRange.location = targetRange.location+(lineModifier*Int(ceil(locationOfTouchInLabel.y)))
}
return NSLocationInRange(adjustedRange, newTargetRange)
}
}
UILabel代码
let tapAction = UITapGestureRecognizer(target: self, action: #selector(self.tapLabel(gesture:)))
let quote = "For full details please see our privacy policy and cookie policy."
let attributedString = NSMutableAttributedString(string: quote)
let string1: String = "privacy policy", string2: String = "cookie policy"
// privacy policy
let rangeString1 = quote.range(of: string1)!
let indexString1: Int = quote.distance(from: quote.startIndex, to: rangeString1.lowerBound)
attributedString.addAttributes(
[.font: <UIfont>,
.foregroundColor: <UI Color>,
.underlineStyle: 0, .underlineColor:UIColor.clear
], range: NSRange(location: indexString1, length: string1.count));
// cookie policy
let rangeString2 = quote.range(of: string2)!
let indexString2: Int = quote.distance(from: quote.startIndex, to: rangeString2.lowerBound )
attributedString.addAttributes(
[.font: <UIfont>,
.foregroundColor: <UI Color>,
.underlineStyle: 0, .underlineColor:UIColor.clear
], range: NSRange(location: indexString2, length: string2.count));
let label = UILabel()
label.frame = CGRect(x: 20, y: 200, width: 375, height: 100)
label.isUserInteractionEnabled = true
label.addGestureRecognizer(tapAction)
label.attributedText = attributedString
编码来识别水龙头
@objc
func tapLabel(gesture: UITapGestureRecognizer) {
if gesture.didTapAttributedTextInLabel(label: <UILabel>, inRange: termsLabelRange {
print("Terms of service")
} else if gesture.didTapAttributedTextInLabel(label:<UILabel> inRange: privacyPolicyLabelRange) {
print("Privacy policy")
} else {
print("Tapped none")
}
}
这是沙玛林。基于Kedar的答案的iOS c#实现。
MyClickableTextViewWithCustomUrlScheme实现与ShouldInteractWithUrl覆盖:
// Inspired from https://stackoverflow.com/a/44112932/15186
internal class MyClickableTextViewWithCustomUrlScheme : UITextView, IUITextViewDelegate
{
public MyClickableTextViewWithCustomUrlScheme()
{
Initialize();
}
public MyClickableTextViewWithCustomUrlScheme(Foundation.NSCoder coder) : base(coder)
{
Initialize();
}
public MyClickableTextViewWithCustomUrlScheme(Foundation.NSObjectFlag t) : base(t)
{
Initialize();
}
public MyClickableTextViewWithCustomUrlScheme(IntPtr handle) : base(handle)
{
Initialize();
}
public MyClickableTextViewWithCustomUrlScheme(CoreGraphics.CGRect frame) : base(frame)
{
Initialize();
}
public MyClickableTextViewWithCustomUrlScheme(CoreGraphics.CGRect frame, NSTextContainer textContainer) : base(frame, textContainer)
{
Initialize();
}
void Initialize()
{
Delegate = this;
}
[Export("textView:shouldInteractWithURL:inRange:")]
public new bool ShouldInteractWithUrl(UITextView textView, NSUrl URL, NSRange characterRange)
{
if (URL.Scheme.CompareTo(@"username") == 0)
{
// Launch the Activity
return false;
}
// The system will handle the URL
return base.ShouldInteractWithUrl(textView, URL, characterRange);
}
}
在c#中转换的objective-C代码变成:
MyClickableTextViewWithCustomUrlScheme uiHabitTile = new MyClickableTextViewWithCustomUrlScheme();
uiHabitTile.Selectable = true;
uiHabitTile.ScrollEnabled = false;
uiHabitTile.Editable = false;
// https://stackoverflow.com/a/34014655/15186
string wholeTitle = @"This is an example by marcelofabri";
NSMutableAttributedString attributedString = new NSMutableAttributedString(wholeTitle);
attributedString.AddAttribute(UIStringAttributeKey.Link,
new NSString("username://marcelofabri"),
attributedString.Value.RangeOfString(@"marcelofabri")
);
NSMutableDictionary<NSString, NSObject> linkAttributes = new NSMutableDictionary<NSString, NSObject>();
linkAttributes[UIStringAttributeKey.ForegroundColor] = UIColor.Green;
linkAttributes[UIStringAttributeKey.UnderlineColor] = UIColor.LightGray;
linkAttributes[UIStringAttributeKey.UnderlineStyle] = new NSNumber((short)NSUnderlineStyle.PatternSolid);
uiHabitTile.AttributedText = attributedString;
确保将Editable = false和Selectable = true设置为能够单击链接。
同样,ScrollEnabled = true允许textview正确地调整其高度大小。
对于完全自定义的链接,你需要使用UIWebView -你可以拦截调用,这样当链接被按下时,你可以转到应用程序的其他部分。
推荐文章
- 如何删除默认的导航栏空间在SwiftUI导航视图
- 如何在iOS中使用Swift编程segue
- Swift -整数转换为小时/分钟/秒
- Swift:声明一个空字典
- 我如何用javascript编程点击链接?
- 在成功提交我的应用程序后,“太多符号文件”
- 首先添加一个UIView,甚至是导航栏
- 我如何改变UIButton标题颜色?
- 在Swift中如何调用GCD主线程上的参数方法?
- NSLayoutConstraints是可动画的吗?
- iOS -构建失败,CocoaPods无法找到头文件
- CFNetwork SSLHandshake iOS 9失败
- 请求失败:不可接受的内容类型:文本/html使用AFNetworking 2.0
- 缺少推荐的图标文件-该包不包含iPhone / iPod Touch的应用程序图标,像素为“120x120”,png格式
- 以编程方式创建segue