Add "...Read More" to the end of UILabel

Swift4 (IOS 11.2)

Readmore at the end of the label without action

extension UILabel {    func addTrailing(with trailingText: String, moreText: String, moreTextFont: UIFont, moreTextColor: UIColor) {        let readMoreText: String = trailingText + moreText        let lengthForVisibleString: Int = self.visibleTextLength        let mutableString: String = self.text!        let trimmedString: String? = (mutableString as NSString).replacingCharacters(in: NSRange(location: lengthForVisibleString, length: ((self.text?.count)! - lengthForVisibleString)), with: "")        let readMoreLength: Int = (readMoreText.count)        let trimmedForReadMore: String = (trimmedString! as NSString).replacingCharacters(in: NSRange(location: ((trimmedString?.count ?? 0) - readMoreLength), length: readMoreLength), with: "") + trailingText        let answerAttributed = NSMutableAttributedString(string: trimmedForReadMore, attributes: [NSAttributedStringKey.font: self.font])        let readMoreAttributed = NSMutableAttributedString(string: moreText, attributes: [NSAttributedStringKey.font: moreTextFont, NSAttributedStringKey.foregroundColor: moreTextColor])        answerAttributed.append(readMoreAttributed)        self.attributedText = answerAttributed    }    var visibleTextLength: Int {        let font: UIFont = self.font        let mode: NSLineBreakMode = self.lineBreakMode        let labelWidth: CGFloat = self.frame.size.width        let labelHeight: CGFloat = self.frame.size.height        let sizeConstraint = CGSize(width: labelWidth, height: CGFloat.greatestFiniteMagnitude)        let attributes: [AnyHashable: Any] = [NSAttributedStringKey.font: font]        let attributedText = NSAttributedString(string: self.text!, attributes: attributes as? [NSAttributedStringKey : Any])        let boundingRect: CGRect = attributedText.boundingRect(with: sizeConstraint, options: .usesLineFragmentOrigin, context: nil)        if boundingRect.size.height > labelHeight {            var index: Int = 0            var prev: Int = 0            let characterSet = CharacterSet.whitespacesAndNewlines            repeat {                prev = index                if mode == NSLineBreakMode.byCharWrapping {                    index += 1                } else {                    index = (self.text! as NSString).rangeOfCharacter(from: characterSet, options: [], range: NSRange(location: index + 1, length: self.text!.count - index - 1)).location                }            } while index != NSNotFound && index < self.text!.count && (self.text! as NSString).substring(to: index).boundingRect(with: sizeConstraint, options: .usesLineFragmentOrigin, attributes: attributes as? [NSAttributedStringKey : Any], context: nil).size.height <= labelHeight            return prev        }        return self.text!.count    }}

Swift 4.2

extension UILabel {        func addTrailing(with trailingText: String, moreText: String, moreTextFont: UIFont, moreTextColor: UIColor) {            let readMoreText: String = trailingText + moreText            let lengthForVisibleString: Int = self.vissibleTextLength            let mutableString: String = self.text!            let trimmedString: String? = (mutableString as NSString).replacingCharacters(in: NSRange(location: lengthForVisibleString, length: ((self.text?.count)! - lengthForVisibleString)), with: "")            let readMoreLength: Int = (readMoreText.count)            let trimmedForReadMore: String = (trimmedString! as NSString).replacingCharacters(in: NSRange(location: ((trimmedString?.count ?? 0) - readMoreLength), length: readMoreLength), with: "") + trailingText            let answerAttributed = NSMutableAttributedString(string: trimmedForReadMore, attributes: [NSAttributedString.Key.font: self.font])            let readMoreAttributed = NSMutableAttributedString(string: moreText, attributes: [NSAttributedString.Key.font: moreTextFont, NSAttributedString.Key.foregroundColor: moreTextColor])            answerAttributed.append(readMoreAttributed)            self.attributedText = answerAttributed        }        var vissibleTextLength: Int {            let font: UIFont = self.font            let mode: NSLineBreakMode = self.lineBreakMode            let labelWidth: CGFloat = self.frame.size.width            let labelHeight: CGFloat = self.frame.size.height            let sizeConstraint = CGSize(width: labelWidth, height: CGFloat.greatestFiniteMagnitude)            let attributes: [AnyHashable: Any] = [NSAttributedString.Key.font: font]            let attributedText = NSAttributedString(string: self.text!, attributes: attributes as? [NSAttributedString.Key : Any])            let boundingRect: CGRect = attributedText.boundingRect(with: sizeConstraint, options: .usesLineFragmentOrigin, context: nil)            if boundingRect.size.height > labelHeight {                var index: Int = 0                var prev: Int = 0                let characterSet = CharacterSet.whitespacesAndNewlines                repeat {                    prev = index                    if mode == NSLineBreakMode.byCharWrapping {                        index += 1                    } else {                        index = (self.text! as NSString).rangeOfCharacter(from: characterSet, options: [], range: NSRange(location: index + 1, length: self.text!.count - index - 1)).location                    }                } while index != NSNotFound && index < self.text!.count && (self.text! as NSString).substring(to: index).boundingRect(with: sizeConstraint, options: .usesLineFragmentOrigin, attributes: attributes as? [NSAttributedString.Key : Any], context: nil).size.height <= labelHeight                return prev            }            return self.text!.count        }    }

Usage

let readmoreFont = UIFont(name: "Helvetica-Oblique", size: 11.0)let readmoreFontColor = UIColor.blueDispatchQueue.main.async {    self.yourLabel.addTrailing(with: "... ", moreText: "Readmore", moreTextFont: readmoreFont!, moreTextColor: readmoreFontColor)}

Result

NOTE: - Action is not included for Readmore

So this is what I did to add the Read More... button to the UITextView, UITextField or UILabel:

- (void)addReadMoreStringToUILabel:(UILabel*)label{    NSString *readMoreText = @" ...Read More";    NSInteger lengthForString = label.text.length;    if (lengthForString >= 30)    {        NSInteger lengthForVisibleString = [self fitString:label.text intoLabel:label];        NSMutableString *mutableString = [[NSMutableString alloc] initWithString:label.text];        NSString *trimmedString = [mutableString stringByReplacingCharactersInRange:NSMakeRange(lengthForVisibleString, (label.text.length - lengthForVisibleString)) withString:@""];        NSInteger readMoreLength = readMoreText.length;        NSString *trimmedForReadMore = [trimmedString stringByReplacingCharactersInRange:NSMakeRange((trimmedString.length - readMoreLength), readMoreLength) withString:@""];        NSMutableAttributedString *answerAttributed = [[NSMutableAttributedString alloc] initWithString:trimmedForReadMore attributes:@{                                                                                                                                        NSFontAttributeName : label.font                                                                                                                                        }];        NSMutableAttributedString *readMoreAttributed = [[NSMutableAttributedString alloc] initWithString:readMoreText attributes:@{                                                                                                                                        NSFontAttributeName : Font(TWRegular, 12.),                                                                                                                                        NSForegroundColorAttributeName : White                                                                                                                                        }];        [answerAttributed appendAttributedString:readMoreAttributed];        label.attributedText = answerAttributed;        UITagTapGestureRecognizer *readMoreGesture = [[UITagTapGestureRecognizer alloc] initWithTarget:self action:@selector(readMoreDidClickedGesture:)];        readMoreGesture.tag = 1;        readMoreGesture.numberOfTapsRequired = 1;        [label addGestureRecognizer:readMoreGesture];        label.userInteractionEnabled = YES;    }    else {        NSLog(@"No need for 'Read More'...");    }}

There is a use of fitString:intoLabel method which can be found here.

As for the UITagTapGestureRecognizer is just a normal UITapGestureRecognizer subclass with a NSInteger property called tag. I did that because I want to identify which Read More... were clicked in I case I have more than one in the same UIViewController. You can use a normal UITapGestureRecognizer.

Enjoy!

Tttattributed label has this feature

https://github.com/TTTAttributedLabel/TTTAttributedLabel

You need to set the "truncation" token as "read more..."

See

attributedTruncationToken

var subTitleLabel = TTTAttributedLabel(frame : frame)    self.addSubview(subTitleLabel)    var trunc = NSMutableAttributedString(string: "...more")    trunc.addAttribute(NSFontAttributeName, value: UIFont.systemFontOfSize(12), range: NSMakeRange(0, 7))    trunc.addAttribute(NSForegroundColorAttributeName, value: UIColor.blueColor(), range: NSMakeRange(0, 7))    subTitleLabel.attributedTruncationToken = trunc    subTitleLabel.numberOfLines = 1    subTitleLabel.autoresizingMask = UIViewAutoresizing.FlexibleHeight | UIViewAutoresizing.FlexibleWidth