Find width of string (swift)

Question

How do I find the width of a string (CGFloat) given the font name and font size?

(The goal is to set the width of a UIView to be just wide enough to hold the string.)

I have two strings: one with "1" repeated 36 times, the other with "M" repeated 36 times. These both fill the width (359.0) of the screen (give or take a little for margins).

I am using using Courier 16, which is monospaced, so I expect the width of both strings to be equal (as they in fact do appear on the screen).

However, using https://stackoverflow.com/a/58782429/8635708 :

• the width of the string with the "1"s is 257.34375
• the width of the string with the "M"s is 492.1875.
• The first is does not fill the screen, the other is way too long.

And using https://stackoverflow.com/a/58795998/8635708 :

• the width of each string is 249.640625.
• At least here, they are the same, but that value clearly does not fill the screen.

Answer 1

let attributedString = NSAttributedString(string: YOUR_STRING, attributes: [NSAttributedString.Key.font: YOUR_FONT])
let line = CTLineCreateWithAttributedString(attributedString)
let lineBounds = CTLineGetBoundsWithOptions(line, .useGlyphPathBounds)
return CGFloat(lineBounds.width)

Answer 2

I think you could create a label and call label.sizeToFit():

let label = UILabel()
label.font = UIFont.init(name: "Courier", size: 16)
label.text = "mmmmmmmmmmmmmmmm"//"1111111111111111"
label.sizeToFit()
print("Width: \(label.frame.size.width)") //153.66666666666666 -> For both strings