How do you get text length in Swift 4?

Question

I am not sure how to update this code:

func textWidth(text: String, font: UIFont?) -> CGFloat
{
    let attributes = font?.fontDescriptor.fontAttributes
    return text.size(withAttributes: attributes).width
}

Swift 4 complain: Cannot convert value of type '[UIFontDescriptor.AttributeName : Any]?' to expected argument type '[NSAttributedStringKey : Any]?'

I don't know why they broke this, but it does not get automatically fixed.

score 6 · Accepted Answer · answered Jan 19 '18 at 06:27

6

(SWIFT 4 Updated)

func textWidth(text: String, font: UIFont?) -> CGFloat {
    let attributes = font != nil ? [NSFontAttributeName: font] : [:]
    return text.size(withAttributes: attributes).width
}

Hope it helps.

answered Jan 19 '18 at 06:27

Avinash Mishra

797
9
19

Thanks, great minds think alike. That seems to be letter for letter the same as OOPer's solution of 27 June 17 I ended up using an extension of UIFont: public func textWidth(s: String) -> CGFloat { return s.size(withAttributes: [NSAttributedStringKey.font: self]).width } – MarkAurelius Jan 21 '18 at 23:25
@MarkAurelius Thanks Buddy :) – Avinash Mishra Jan 22 '18 at 04:22

score 5 · Answer 2 · answered Jun 27 '17 at 14:05

I guess, you want to write something like this:

(Swift 4)

func textWidth(text: String, font: UIFont?) -> CGFloat {
    let attributes = font != nil ? [NSAttributedStringKey.font: font!] : [:]
    return text.size(withAttributes: attributes).width
}

(Swift 3)

func textWidth(text: String, font: UIFont?) -> CGFloat {
    let attributes = font != nil ? [NSFontAttributeName: font!] : [:]
    return text.size(attributes: attributes).width
}

fontAttributes is not a valid input for size(withAttributes:) (size(attributes:) in Swift 3) even if the type matches.

Thanks! That seems to work. I'll stare at it for a while to try to understand the thinking. — MarkAurelius, Jun 28 '17 at 01:10

score 0 · Answer 3 · answered Jun 28 '17 at 01:45

0

An alternative way to do this in Swift 4, avoiding the handling of the optional, is like this:

  extension UIFont { 


    func textWidth(s: String) -> CGFloat
    {
        return s.size(withAttributes: [NSAttributedStringKey.font: self]).width
    }

}

answered Jun 28 '17 at 01:45

MarkAurelius

1,203
1
14
27

that return wrong size for me :( let font = UIFont.systemFont(ofSize: 16) -> return CGSize(12 + font.textWidth(s: service.licenseName!), 50) -> wrong size, label does not show full text – famfamfam Oct 30 '19 at 04:33
Darn. Did any other approach work? That is early is Swift's history. – MarkAurelius May 28 '20 at 08:02

How do you get text length in Swift 4?

3 Answers3