How to check if UILabel is truncated?

Question

I have a UILabel that can be varying lengths depending on whether or not my app is running in portrait or landscape mode on an iPhone or iPad. When the text is

Answer 1

Swift 3

You can count the number of lines after assigning the string and compare to the max number of lines of the label.

import Foundation
import UIKit

extension UILabel {
    
    func countLabelLines() -> Int {
        // Call self.layoutIfNeeded() if your view is uses auto layout
        let myText = self.text! as NSString
        let attributes = [NSFontAttributeName : self.font]
        
        let labelSize = myText.boundingRect(with: CGSize(width: self.bounds.width, height: CGFloat.greatestFiniteMagnitude), options: NSStringDrawingOptions.usesLineFragmentOrigin, attributes: attributes, context: nil)
        return Int(ceil(CGFloat(labelSize.height) / self.font.lineHeight))
    }
    
    func isTruncated() -> Bool {
        guard numberOfLines > 0 else { return false }
        return countLabelLines() > numberOfLines
    }
}