FontFamily protocol helps to enumerate and access font face strongly typed.

FontFamily.md

FontFamily Enumerated (Swift)

Helps to quick enumarate font faces by strong typed enumerators.

Usage

enum Arial: String, FontFamily {
  case regular = "Arial-Regular"
  case bold = "Arial-Bold"
  case italic = "Arial-Italic"
  case extraBold = "Arial-ExtraBold"
}

// using strong typed font family:
let bodyFont = Arial.regular.withSize(12)
let titleFont = Arial.bold.withSize(26)

License

MIT

FontFamily.swift

/*
  FontFamily.swift
  
  MIT License
  Copyright (c) 2020 Jan Cassio
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/

import SwiftUI

/**
 * Provide a strong typed API for enumerated font family.
 *
 * FontFamily protocol enable easy font family setup using enumerators of string type
 * that just need to match the family name of desired font.
 *
 * ```
 * enum Arial: String, FontFamily {
 *   case regular = "Arial-Regular"
 *   case bold = "Arial-Bold"
 *   case italic = "Arial-Italic"
 *   case extraBold = "Arial-ExtraBold"
 * }
 *
 * // using strong typed font family:
 * let bodyFont = Arial.regular.withSize(12)
 * let titleFont = Arial.bold.withSize(26)
 * ```
 */
fileprivate protocol FontFamily {
  var fontName: String { get }
  func withSize(_ size: CGFloat) -> Font
}


extension FontFamily where Self: RawRepresentable, RawValue == String {
  var fontName: String {
    self.rawValue
  }
  
  func withSize(_ size: CGFloat) -> Font {
    Font.custom(fontName, size: size)
  }
}