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)
}
}
其他回答
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。
以下是NAlexN的回答。
class TapabbleLabel: UILabel {
let layoutManager = NSLayoutManager()
let textContainer = NSTextContainer(size: CGSize.zero)
var textStorage = NSTextStorage() {
didSet {
textStorage.addLayoutManager(layoutManager)
}
}
var onCharacterTapped: ((label: UILabel, characterIndex: Int) -> Void)?
let tapGesture = UITapGestureRecognizer()
override var attributedText: NSAttributedString? {
didSet {
if let attributedText = attributedText {
textStorage = NSTextStorage(attributedString: attributedText)
} else {
textStorage = NSTextStorage()
}
}
}
override var lineBreakMode: NSLineBreakMode {
didSet {
textContainer.lineBreakMode = lineBreakMode
}
}
override var numberOfLines: Int {
didSet {
textContainer.maximumNumberOfLines = numberOfLines
}
}
/**
Creates a new view with the passed coder.
:param: aDecoder The a decoder
:returns: the created new view.
*/
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setUp()
}
/**
Creates a new view with the passed frame.
:param: frame The frame
:returns: the created new view.
*/
override init(frame: CGRect) {
super.init(frame: frame)
setUp()
}
/**
Sets up the view.
*/
func setUp() {
userInteractionEnabled = true
layoutManager.addTextContainer(textContainer)
textContainer.lineFragmentPadding = 0
textContainer.lineBreakMode = lineBreakMode
textContainer.maximumNumberOfLines = numberOfLines
tapGesture.addTarget(self, action: #selector(TapabbleLabel.labelTapped(_:)))
addGestureRecognizer(tapGesture)
}
override func layoutSubviews() {
super.layoutSubviews()
textContainer.size = bounds.size
}
func labelTapped(gesture: UITapGestureRecognizer) {
guard gesture.state == .Ended else {
return
}
let locationOfTouch = gesture.locationInView(gesture.view)
let textBoundingBox = layoutManager.usedRectForTextContainer(textContainer)
let textContainerOffset = CGPoint(x: (bounds.width - textBoundingBox.width) / 2 - textBoundingBox.minX,
y: (bounds.height - textBoundingBox.height) / 2 - textBoundingBox.minY)
let locationOfTouchInTextContainer = CGPoint(x: locationOfTouch.x - textContainerOffset.x,
y: locationOfTouch.y - textContainerOffset.y)
let indexOfCharacter = layoutManager.characterIndexForPoint(locationOfTouchInTextContainer,
inTextContainer: textContainer,
fractionOfDistanceBetweenInsertionPoints: nil)
onCharacterTapped?(label: self, characterIndex: indexOfCharacter)
}
}
然后你可以在你的viewDidLoad方法中创建一个类的实例,就像这样:
let label = TapabbleLabel()
label.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(label)
view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("V:|-[view]-|",
options: [], metrics: nil, views: ["view" : label]))
view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("H:|-[view]-|",
options: [], metrics: nil, views: ["view" : label]))
let attributedString = NSMutableAttributedString(string: "String with a link", attributes: nil)
let linkRange = NSMakeRange(14, 4); // for the word "link" in the string above
let linkAttributes: [String : AnyObject] = [
NSForegroundColorAttributeName : UIColor.blueColor(), NSUnderlineStyleAttributeName : NSUnderlineStyle.StyleSingle.rawValue,
NSLinkAttributeName: "http://www.apple.com"]
attributedString.setAttributes(linkAttributes, range:linkRange)
label.attributedText = attributedString
label.onCharacterTapped = { label, characterIndex in
if let attribute = label.attributedText?.attribute(NSLinkAttributeName, atIndex: characterIndex, effectiveRange: nil) as? String,
let url = NSURL(string: attribute) {
UIApplication.sharedApplication().openURL(url)
}
}
最好有一个自定义属性,以便在点击字符时使用。它是NSLinkAttributeName,但可以是任何东西你可以使用那个值去做其他的事情除了打开一个url,你可以做任何自定义动作。
下面是超链接UILabel的示例代码: 来源:http://sickprogrammersarea.blogspot.in/2014/03/adding-links-to-uilabel.html
#import "ViewController.h"
#import "TTTAttributedLabel.h"
@interface ViewController ()
@end
@implementation ViewController
{
UITextField *loc;
TTTAttributedLabel *data;
}
- (void)viewDidLoad
{
[super viewDidLoad];
UILabel *lbl = [[UILabel alloc] initWithFrame:CGRectMake(5, 20, 80, 25) ];
[lbl setText:@"Text:"];
[lbl setFont:[UIFont fontWithName:@"Verdana" size:16]];
[lbl setTextColor:[UIColor grayColor]];
loc=[[UITextField alloc] initWithFrame:CGRectMake(4, 20, 300, 30)];
//loc.backgroundColor = [UIColor grayColor];
loc.borderStyle=UITextBorderStyleRoundedRect;
loc.clearButtonMode=UITextFieldViewModeWhileEditing;
//[loc setText:@"Enter Location"];
loc.clearsOnInsertion = YES;
loc.leftView=lbl;
loc.leftViewMode=UITextFieldViewModeAlways;
[loc setDelegate:self];
[self.view addSubview:loc];
[loc setRightViewMode:UITextFieldViewModeAlways];
CGRect frameimg = CGRectMake(110, 70, 70,30);
UIButton *srchButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
srchButton.frame=frameimg;
[srchButton setTitle:@"Go" forState:UIControlStateNormal];
[srchButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
srchButton.backgroundColor=[UIColor clearColor];
[srchButton addTarget:self action:@selector(go:) forControlEvents:UIControlEventTouchDown];
[self.view addSubview:srchButton];
data = [[TTTAttributedLabel alloc] initWithFrame:CGRectMake(5, 120,self.view.frame.size.width,200) ];
[data setFont:[UIFont fontWithName:@"Verdana" size:16]];
[data setTextColor:[UIColor blackColor]];
data.numberOfLines=0;
data.delegate = self;
data.enabledTextCheckingTypes=NSTextCheckingTypeLink|NSTextCheckingTypePhoneNumber;
[self.view addSubview:data];
}
- (void)attributedLabel:(TTTAttributedLabel *)label didSelectLinkWithURL:(NSURL *)url
{
NSString *val=[[NSString alloc]initWithFormat:@"%@",url];
if ([[url scheme] hasPrefix:@"mailto"]) {
NSLog(@" mail URL Selected : %@",url);
MFMailComposeViewController *comp=[[MFMailComposeViewController alloc]init];
[comp setMailComposeDelegate:self];
if([MFMailComposeViewController canSendMail])
{
NSString *recp=[[val substringToIndex:[val length]] substringFromIndex:7];
NSLog(@"Recept : %@",recp);
[comp setToRecipients:[NSArray arrayWithObjects:recp, nil]];
[comp setSubject:@"From my app"];
[comp setMessageBody:@"Hello bro" isHTML:NO];
[comp setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
[self presentViewController:comp animated:YES completion:nil];
}
}
else{
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:val]];
}
}
-(void)mailComposeController:(MFMailComposeViewController *)controller didFinishWithResult:(MFMailComposeResult)result error:(NSError *)error{
if(error)
{
UIAlertView *alrt=[[UIAlertView alloc]initWithTitle:@"Erorr" message:@"Some error occureed" delegate:nil cancelButtonTitle:@"" otherButtonTitles:nil, nil];
[alrt show];
[self dismissViewControllerAnimated:YES completion:nil];
}
else{
[self dismissViewControllerAnimated:YES completion:nil];
}
}
- (void)attributedLabel:(TTTAttributedLabel *)label didSelectLinkWithPhoneNumber:(NSString *)phoneNumber
{
NSLog(@"Phone Number Selected : %@",phoneNumber);
UIDevice *device = [UIDevice currentDevice];
if ([[device model] isEqualToString:@"iPhone"] ) {
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:[NSString stringWithFormat:@"tel:%@",phoneNumber]]];
} else {
UIAlertView *Notpermitted=[[UIAlertView alloc] initWithTitle:@"Alert" message:@"Your device doesn't support this feature." delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
[Notpermitted show];
}
}
-(void)go:(id)sender
{
[data setText:loc.text];
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(@"Reached");
[loc resignFirstResponder];
}
有些答案并不如我所料。这是Swift解决方案,也支持textAlignment和多行。不需要子类化,只是这个UITapGestureRecognizer扩展:
import UIKit
extension UITapGestureRecognizer {
func didTapAttributedString(_ string: String, in label: UILabel) -> Bool {
guard let text = label.text else {
return false
}
let range = (text as NSString).range(of: string)
return self.didTapAttributedText(label: label, inRange: range)
}
private func didTapAttributedText(label: UILabel, inRange targetRange: NSRange) -> Bool {
guard let attributedText = label.attributedText else {
assertionFailure("attributedText must be set")
return false
}
let textContainer = createTextContainer(for: label)
let layoutManager = NSLayoutManager()
layoutManager.addTextContainer(textContainer)
let textStorage = NSTextStorage(attributedString: attributedText)
if let font = label.font {
textStorage.addAttribute(NSAttributedString.Key.font, value: font, range: NSMakeRange(0, attributedText.length))
}
textStorage.addLayoutManager(layoutManager)
let locationOfTouchInLabel = location(in: label)
let textBoundingBox = layoutManager.usedRect(for: textContainer)
let alignmentOffset = aligmentOffset(for: label)
let xOffset = ((label.bounds.size.width - textBoundingBox.size.width) * alignmentOffset) - textBoundingBox.origin.x
let yOffset = ((label.bounds.size.height - textBoundingBox.size.height) * alignmentOffset) - textBoundingBox.origin.y
let locationOfTouchInTextContainer = CGPoint(x: locationOfTouchInLabel.x - xOffset, y: locationOfTouchInLabel.y - yOffset)
let characterTapped = layoutManager.characterIndex(for: locationOfTouchInTextContainer, in: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
let lineTapped = Int(ceil(locationOfTouchInLabel.y / label.font.lineHeight)) - 1
let rightMostPointInLineTapped = CGPoint(x: label.bounds.size.width, y: label.font.lineHeight * CGFloat(lineTapped))
let charsInLineTapped = layoutManager.characterIndex(for: rightMostPointInLineTapped, in: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
return characterTapped < charsInLineTapped ? targetRange.contains(characterTapped) : false
}
private func createTextContainer(for label: UILabel) -> NSTextContainer {
let textContainer = NSTextContainer(size: label.bounds.size)
textContainer.lineFragmentPadding = 0.0
textContainer.lineBreakMode = label.lineBreakMode
textContainer.maximumNumberOfLines = label.numberOfLines
return textContainer
}
private func aligmentOffset(for label: UILabel) -> CGFloat {
switch label.textAlignment {
case .left, .natural, .justified:
return 0.0
case .center:
return 0.5
case .right:
return 1.0
@unknown default:
return 0.0
}
}
}
用法:
class ViewController: UIViewController {
@IBOutlet var label : UILabel!
let selectableString1 = "consectetur"
let selectableString2 = "cupidatat"
override func viewDidLoad() {
super.viewDidLoad()
let text = "Lorem ipsum dolor sit amet, \(selectableString1) adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat \(selectableString2) non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
label.attributedText = NSMutableAttributedString(attributedString: NSAttributedString(string: text))
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(labelTapped))
label.addGestureRecognizer(tapGesture)
label.isUserInteractionEnabled = true
}
@objc func labelTapped(gesture: UITapGestureRecognizer) {
if gesture.didTapAttributedString(selectableString1, in: label) {
print("\(selectableString1) tapped")
} else if gesture.didTapAttributedString(selectableString2, in: label) {
print("\(selectableString2) tapped")
} else {
print("Text tapped")
}
}
}
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)
}
}
}}
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