Annotated is a small library that let you annotate your strings with semantic annotations.
Once a String is annotated, you can transform it to a NSAttributedString or a SwiftUI Text
It allows you, for example, to semantically annotate a String in your View Model without thinking about the final visual style, and then render your String in your View as an NSAttributedString.
- iOS 11.0
- Swift 5.1
Annotated is available through CocoaPods and SwiftPM
First, you need to define your annotations. Using an enum is generally great for that.
enum AddressAnnotations: Hashable {
case city, postalCode, highlighted
}Then you can create you Annotated<AddressAnnotations> string using a string literal. You can directly annotate parts of your string thanks to custom String Interpolation.
var string: Annotated<AddressAnnotations> = """
1 Infinite Loop
\("Cupertino", .city), CA \(95014, .postalCode)
"""You can also add annotations manually.
string.addAnnotation(.highlighted, at: 0..<1)
string.addAnnotation(.highlighted, forOccurencesOf: "in", options: .caseInsensitive)Finally, you can render your string into an NSAttributedString or a SwiftUI Text using provided factory methods.
let attributedString = string.makeAttributedString { annotation in
switch annotation {
case nil: return [.font: UIFont.systemFont(ofSize: 24)]
case .city: return [.font: UIFont.boldSystemFont(ofSize: 24)]
case .postalCode: return [.underlineStyle: NSNumber(value: NSUnderlineStyle.single.rawValue)]
case .highlighted: return [.foregroundColor: UIColor.systemRed]
}
}let text = string.makeText { annotation in
switch annotation {
case nil: return { $0.font(.system(size: 24)) }
case .city: return { $0.bold() }
case .postalCode: return { $0.underline() }
case .highlighted: return { $0.foregroundColor(.red) }
}
}
Annotated is available under the MIT license. See the LICENSE file for more info.