Xcode Previews for Dynamic Font Sizes: Boosting App Accessibility for 25% of iOS Users

In the realm of iOS app development, understanding user preferences is paramount. Recent studies, including insights from PSPDFKit research and observations from @bloom_life, reveal a significant trend: over a quarter of iOS users prefer non-default text sizes. This highlights the necessity of dynamic font sizes for modern app development.

struct ExampleView: View {
    var body: some View {
        VStack{
            Color.green
            Text("Dreamcraft.io").foregroundColor(.black).fontWeight(.black)
            Color.blue
        }
    }
}

In the app design phase, using Xcode previews effectively can give developers an edge. These previews allow one to simulate how an app interface adapts when users tweak the dynamic font size. Given that SwiftUI’s API preview is a vital component, it’s recommended to tap into its full potential. In this context, use the environment modifier to set the sizeCategory keypath to .accessibilityLarge.

struct Example_Previews: PreviewProvider {
   static var previews: some View {
     ExampleView().environment(\.sizeCategory, .accessibilityLarge)
   }
}

While one could embed this view in a group, allocating a distinctive sizeCategory to each ExampleView, there’s a more streamlined approach. SwiftUI introduces the for each feature. This ensures that for every distinct sizeCategory, there’s a corresponding preview.

struct Example_Previews: PreviewProvider {
  static var previews: some View {
    ForEach(ContentSizeCategory.allCases, id: \.self){ item in
      ExampleView().environment(\.sizeCategory, item)
    }
  }
}

Conclusion

Prioritizing dynamic font sizes is integral to producing an iOS app that’s both user-friendly and accessible. By leveraging Xcode previews in conjunction with SwiftUI, developers can effortlessly cater to a broader audience. Investing time in these nuances not only amplifies the user experience but also underscores a developer’s dedication to inclusivity. In the ever-evolving digital landscape, it’s such attention to detail that distinguishes a top-tier app, ensuring it resonates effectively with the target audience.

Written by

Dragos Resetnic

I have over 15 years of experience in software development, with a particular focus on the Apple platform. My expertise lies in developing iOS applications for a wide range of clients. Along the way, I've had the opportunity to present technical talks and write articles on iOS/Swift, sharing my knowledge and insights with the community.