Detect whether a font is bold/italic on iOS?

Question

Given a UIFont or a CTFont, how can I tell whether the font is bold/italic?

Cameron Lowell Palmer · Answer 1 · 2015-12-24T10:17:22.253

45

iOS7 Font Descriptor

No reason to use Core Text, you can simply ask UIFont for the fontDescriptor.

        UIFont *font = [UIFont boldSystemFontOfSize:17.0f];
        UIFontDescriptor *fontDescriptor = font.fontDescriptor;
        UIFontDescriptorSymbolicTraits fontDescriptorSymbolicTraits = fontDescriptor.symbolicTraits;
        BOOL isBold = (fontDescriptorSymbolicTraits & UIFontDescriptorTraitBold) != 0;

Going forward this is probably the easiest way to ask about the traits of a font.

edited Dec 24 '15 at 10:17

answered Dec 11 '13 at 09:31

Cameron Lowell Palmer

21,528
7
125
126

Don't cast `uint32_t` to `BOOL`, it will cause you problems. Use `BOOL isBold = (fontDescriptorSymbolicTraits & UIFontDescriptorTraitBold) != 0` or `BOOL isBold = !!(fontDescriptorSymbolicTraits & UIFontDescriptorTraitBold)` instead. – Jeffery Thomas Nov 24 '15 at 03:37

Arjan · Answer 2 · 2023-01-02T13:08:28.013

39

If you want to do this with Swift:

extension UIFont {
    var isBold: Bool {
        return fontDescriptor.symbolicTraits.contains(.traitBold)
    }
    
    var isItalic: Bool {
        return fontDescriptor.symbolicTraits.contains(.traitItalic)
    }
}

Usage:

let font: UIFont = UIFont.preferredFont(forTextStyle: .headline)
if font.isBold {
  print("it's bold..")
}

edited Jan 02 '23 at 13:08

answered Feb 25 '16 at 15:36

Arjan

16,210
5
30
40

13

@JanGreve please reconsider your downvote, Answering old questions when there's new solutions available is a good thing, and I added Swift tag for clarity. – Arjan Feb 25 '16 at 18:44
4

I removed the swift tag again. There is no way the author could've meant to ask for swift, so your edit clearly conflicts with the author's intend. Other than that, you are right; a new objective-c technique would have been fine. – Tobi Nary Feb 25 '16 at 18:47
3

Note: this is currently being [discussed on meta](http://meta.stackoverflow.com/questions/317716/are-only-tags-allowed-that-the-author-could-have-intended) @Jan – Shog9 Feb 25 '16 at 19:42

score 35 · Accepted Answer · answered Jul 10 '11 at 04:28

35

Looking at the font's name won't always work. Consider the font "Courier Oblique" (which is italic) or "HoeflerText-Black" (which is bold), Neither of those contain "bold" or "italic" in their names.

Given a font as a CTFontRef, the proper way to determine whether it's bold or italic is to use the CTFontGetSymbolicTraits function:

CTFontRef font = CTFontCreateWithName((CFStringRef)@"Courier Oblique", 10, NULL);
CTFontSymbolicTraits traits = CTFontGetSymbolicTraits(font);
BOOL isItalic = ((traits & kCTFontItalicTrait) == kCTFontItalicTrait);
BOOL isBold = ((traits & kCTFontBoldTrait) == kCTFontBoldTrait);
NSLog(@"Italic: %i Bold: %i", isItalic, isBold);
CFRelease(font);

answered Jul 10 '11 at 04:28

omz

53,243
5
129
141

Thanks, I think this is a really clean way of doing this. One more question. Let's say I have a CTFont, how can I make it bold? – aryaxt Jul 10 '11 at 16:34
1

Use the `CTFontCreateCopyWithSymbolicTraits` function. – omz Jul 10 '11 at 16:44
```isItalic``` doesn't work with Superclarendon, Marion and Gill Sans fonts. – Shmidt Sep 13 '14 at 10:10

John Rogers · Answer 4 · 2018-11-01T02:06:55.567

11

Answer for Swift 3/4 based on Arjan's answer:

extension UIFont {
    var isBold: Bool {
        return fontDescriptor.symbolicTraits.contains(.traitBold)
    }

    var isItalic: Bool {
        return fontDescriptor.symbolicTraits.contains(.traitItalic)
    }
}

edited Nov 01 '18 at 02:06

answered Apr 20 '18 at 04:59

John Rogers

2,192
19
29

Detect whether a font is bold/italic on iOS?

4 Answers4

iOS7 Font Descriptor

Linked