L'erreur "La classe" Environnement "ne peut pas être utilisée comme attribut" reçue lorsque @Environment est appelé

J'essaie d'inclure Dynamic Type avec une police personnalisée dans SwiftUI, et cette erreur continue d'être appelée lorsque j'essaie d'obtenir la sizeCategory l'environnement.

J'ai essayé d'utiliser @Environment pour obtenir des objets autres que sizeCategory , mais cela continue de sizeCategory la même erreur.

J'utilise une modification du code de ce post StackOverflow, sur Xcode 11 beta 5. Cela semble fonctionner pour tout le monde là-bas, donc je ne comprends vraiment pas pourquoi cela ne fonctionne pas pour moi.

//
//  Fonts.swift
//  Team Study
//
//  Created by Aditya Chugh on 2019-07-02.
//  Copyright © 2019 Aditya Chugh. All rights reserved.
//

import SwiftUI

class Rawline {

  static let extraLight = "RawlineExtraLight-Regular"
  static let extraLightItalic = "RawlineExtraLight-Italic"

  static let light = "RawlineLight-Regular"
  static let lightItalic = "RawlineLight-Italic"

  static let thin = "RawlineThin-Regular"
  static let thinItalic = "Rawline-ThinItalic"

  static let regular = "Rawline-Regular"
  static let italic = "Rawline-Italic"

  static let medium = "RawlineMedium-Regular"
  static let mediumItalic = "RawlineMedium-Italic"

  static let semiBold = "RawlineSemiBold-Regular"
  static let semiBoldItalic = "RawlineSemiBold-Italic"

  static let bold = "Rawline-Bold"
  static let boldItalic = "Rawline-BoldItalic"

  static let extraBold = "RawlineExtraBold-Regular"
  static let extraBoldItalic = "RawlineExtraBold-Italic"

  static let black = "RawlineBlack-Regular"
  static let blackItalic = "RawlineBlack-Italic"

}

struct RawlineFont: ViewModifier {
  var textStyle: Font.TextStyle

  @Environment(\.sizeCategory) var sizeCategory : ContentSizeCategory

  init(_ textStyle: Font.TextStyle = .body) {
    self.textStyle = textStyle
  }

  func body(content: Content) -> some View {
    content.font(getFont())
  }

  func getFont() -> Font {
    switch(self.sizeCategory) {
    case .extraSmall:
      return Font.custom("Rawline", size: 16 * getStyleFactor())
    case .small:
      return Font.custom("Rawline", size: 21 * getStyleFactor())
    case .medium:
      return Font.custom("Rawline", size: 24 * getStyleFactor())
    case .large:
      return Font.custom("Rawline", size: 28 * getStyleFactor())
    case .extraLarge:
      return Font.custom("Rawline", size: 32 * getStyleFactor())
    case .extraExtraLarge:
      return Font.custom("Rawline", size: 36 * getStyleFactor())
    case .extraExtraExtraLarge:
      return Font.custom("Rawline", size: 40 * getStyleFactor())
    case .accessibilityMedium:
      return Font.custom("Rawline", size: 48 * getStyleFactor())
    case .accessibilityLarge:
      return Font.custom("Rawline", size: 52 * getStyleFactor())
    case .accessibilityExtraLarge:
      return Font.custom("Rawline", size: 60 * getStyleFactor())
    case .accessibilityExtraExtraLarge:
      return Font.custom("Rawline", size: 66 * getStyleFactor())
    case .accessibilityExtraExtraExtraLarge:
      return Font.custom("Rawline", size: 72 * getStyleFactor())
    @unknown default:
      return Font.custom("Rawline", size: 36 * getStyleFactor())
    }
  }

  func getStyleFactor() -> CGFloat {
    switch textStyle {
    case .caption:
      return 0.6
    case .footnote:
      return 0.7
    case .subheadline:
      return 0.8
    case .callout:
      return 0.9
    case .body:
      return 1.0
    case .headline:
      return 1.2
    case .title:
      return 1.5
    case .largeTitle:
      return 2.0
    @unknown default:
      return 1.0
    }
  }

}

Message d'erreur

Fichier de code complet:

struct RawlineFont: ViewModifier {
  var textStyle: Font.TextStyle

  @Environment(\.sizeCategory) var sizeCategory : ContentSizeCategory

  init(_ textStyle: Font.TextStyle = .body) {
    self.textStyle = textStyle
  }

  func body(content: Content) -> some View {
    content.font(getFont())
  }

  func getFont() -> Font {
    switch(self.sizeCategory) {
    case .extraSmall:
      return Font.custom("Rawline", size: 16 * getStyleFactor())
    case .small:
      return Font.custom("Rawline", size: 21 * getStyleFactor())
    case .medium:
      return Font.custom("Rawline", size: 24 * getStyleFactor())
    case .large:
      return Font.custom("Rawline", size: 28 * getStyleFactor())
    case .extraLarge:
      return Font.custom("Rawline", size: 32 * getStyleFactor())
    case .extraExtraLarge:
      return Font.custom("Rawline", size: 36 * getStyleFactor())
    case .extraExtraExtraLarge:
      return Font.custom("Rawline", size: 40 * getStyleFactor())
    case .accessibilityMedium:
      return Font.custom("Rawline", size: 48 * getStyleFactor())
    case .accessibilityLarge:
      return Font.custom("Rawline", size: 52 * getStyleFactor())
    case .accessibilityExtraLarge:
      return Font.custom("Rawline", size: 60 * getStyleFactor())
    case .accessibilityExtraExtraLarge:
      return Font.custom("Rawline", size: 66 * getStyleFactor())
    case .accessibilityExtraExtraExtraLarge:
      return Font.custom("Rawline", size: 72 * getStyleFactor())
    @unknown default:
      return Font.custom("Rawline", size: 36 * getStyleFactor())
    }
  }

  func getStyleFactor() -> CGFloat {
    switch textStyle {
    case .caption:
      return 0.6
    case .footnote:
      return 0.7
    case .subheadline:
      return 0.8
    case .callout:
      return 0.9
    case .body:
      return 1.0
    case .headline:
      return 1.2
    case .title:
      return 1.5
    case .largeTitle:
      return 2.0
    @unknown default:
      return 1.0
    }
  }

}