let bodyFontDescriptor = UIFontDescriptor .preferredFontDescriptor(withTextStyle: UIFontTextStyle.body) let bodyMonospacedFontDescriptor = bodyFontDescriptor.addingAttributes( [ UIFontDescriptorFeatureSettingsAttribute: [ [ UIFontFeatureTypeIdentifierKey: kTextSpacingType, UIFontFeatureSelectorIdentifierKey: kMonospacedTextSelector ] ] ]) let bodyMonospacedFont = UIFont(descriptor: bodyMonospacedFontDescriptor, size: 0.0) textview.font = bodyMonospacedFont This produces text with characters of variable width. I need to get a monospace font without hardcoding courier new and fixed size. Deployment target is ios 9.0
1 Answers
Answers 1
Here is an extension to UIFontDescriptor that returns a preferred monospaced font descriptor for a given text style. There is no simple way to get a fully monospaced font using UIFont or UIFontDescriptor. This solution attempts to find a good monospaced font and falls back to Courier if needed.
extension UIFontDescriptor { static let monoDescriptor: UIFontDescriptor = { // Attempt to find a good monospaced, non-bold, non-italic font for family in UIFont.familyNames { for name in UIFont.fontNames(forFamilyName: family) { let f = UIFont(name: name, size: 12)! let fd = f.fontDescriptor let st = fd.symbolicTraits if st.contains(.traitMonoSpace) && !st.contains(.traitBold) && !st.contains(.traitItalic) && !st.contains(.traitExpanded) && !st.contains(.traitCondensed) { return fd } } } return UIFontDescriptor(name: "Courier", size: 0) // fallback }() class func preferredMonoFontDescriptor(withTextStyle style: UIFontTextStyle) -> UIFontDescriptor { // Use the following line if you need a fully monospaced font let monoDescriptor = UIFontDescriptor.monoDescriptor // Use the following two lines if you only need monospaced digits in the font //let monoDigitFont = UIFont.monospacedDigitSystemFont(ofSize: 0, weight: .regular) //let monoDescriptor = monoDigitFont.fontDescriptor // Get the non-monospaced preferred font let defaultFontDescriptor = preferredFontDescriptor(withTextStyle: style) // Remove any attributes that specify a font family or name and remove the usage // This will leave other attributes such as size and weight, etc. var fontAttrs = defaultFontDescriptor.fontAttributes fontAttrs.removeValue(forKey: .family) fontAttrs.removeValue(forKey: .name) fontAttrs.removeValue(forKey: .init(rawValue: "NSCTFontUIUsageAttribute")) let monospacedFontDescriptor = monoDescriptor.addingAttributes(fontAttrs) return monospacedFontDescriptor.withSymbolicTraits(defaultFontDescriptor.symbolicTraits) ?? monospacedFontDescriptor } } Note the comments about whether you need a font that is fully monospaced or a font that just has monospaced digits. Comment/Uncomment those lines to suit your specific needs.
Sample usage:
let bodyMonospacedFont = UIFont(descriptor: .preferredMonoFontDescriptor(withTextStyle: .body), size: 0) textview.font = bodyMonospacedFont The following is some test code to confirm that the results of preferredMonoFontDescriptor(withTextStyle:) works properly for all styles:
let textStyles: [UIFontTextStyle] = [ .body, .callout, .caption1, .caption2, .footnote, .headline, .subheadline, .largeTitle, .title1, .title2, .title3 ] for style in textStyles { let nfont = UIFont(descriptor: .preferredFontDescriptor(withTextStyle: style), size: 0) let mfont = UIFont(descriptor: .preferredMonoFontDescriptor(withTextStyle: style), size: 0) print(style) print(nfont) print(mfont) } If you compare each pair of results, they have the same size, weight, and style, just a different font.
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