How to find actual number of lines of UILabel?

Question

How can I find the actual number of lines of a UILabel after I have initialized it with a text and a font? I have set

Answer 1

Firstly set text in UILabel

First Option :

Firstly calculate height for text according to font :

NSInteger lineCount = 0;
CGSize labelSize = (CGSize){yourLabel.frame.size.width, MAXFLOAT};
CGRect requiredSize = [self boundingRectWithSize:labelSize  options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName: yourLabel.font} context:nil];

Now calculate number of lines :

int charSize = lroundf(yourLabel.font.lineHeight);
int rHeight = lroundf(requiredSize.height);
lineCount = rHeight/charSize;
NSLog(@"No of lines: %i",lineCount);

Second Option :

 NSInteger lineCount = 0;
 CGSize textSize = CGSizeMake(yourLabel.frame.size.width, MAXFLOAT);
 int rHeight = lroundf([yourLabel sizeThatFits:textSize].height);
 int charSize = lroundf(yourLabel.font.lineHeight);
 lineCount = rHeight/charSize;
 NSLog(@"No of lines: %i",lineCount);

Answer 2

Swift 5.2

The main point to make it work for me was to call label.layoutIfNeeded() because I was using autoLayout, otherwise it doesnt work.

func actualNumberOfLines(label: UILabel) -> Int {
        // You have to call layoutIfNeeded() if you are using autoLayout
        label.layoutIfNeeded()

        let myText = label.text! as NSString

        let rect = CGSize(width: label.bounds.width, height: CGFloat.greatestFiniteMagnitude)
        let labelSize = myText.boundingRect(with: rect, options: .usesLineFragmentOrigin, attributes: [NSAttributedString.Key.font: label.font as Any], context: nil)

        return Int(ceil(CGFloat(labelSize.height) / label.font.lineHeight))
    }

Credits to: https://gist.github.com/fuxingloh/ccf26bb68f4b8e6cfd02, which provided the solution in an older swift version, and for mentioning the importance of layoutIfNeeded().