Localization with String Catalogs

This project provides an iOS app with a string catalog for managing localizable strings. It is supposed to show options of how to store localizable keys so that a string catalog can automatically manage them.

Resources

• Localizing and varying text with a string catalog
• Discover String Catalogs
• Editing XLIFF and string catalog files
• LocalizedStringResource

Traits

ID	Type	SC compatible	SwiftUI	SwiftUI previews	UIKit	Key Access	Parameters
a	Swift.String.LocalizationValue	✅	⚠️	❌	⚠️	❌	❌
b	SwiftUI.LocalizedStringKey	✅	✅	✅	❌	❌	❌
c	Foundation.LocalizedStringResource	✅	✅	✅	⚠️	✅	✅
d	SwiftUI.Text	✅	✅	✅	❌	❌	✅
f	Foundation.NSLocalizedString	✅	✅	❌	✅	❌	✅
g	Swift.String extension	❌	✅	❌	✅	❌	❌
h	Swift.String(localized:)	✅	✅	❌	✅	❌	✅

Legend

Key	Description
ID	The variable name in the Examples
Type	The type to store a localizable key
SC compatible	Does the string catalog automatically find the specified keys in the project?
SwiftUI	Do SwiftUI symbols come with an interface?
SwiftUI previews	Do SwiftUI previews automatically reflect the current locale from environment?
UIKit	Do UIKit symbols come with an interface?
Key Access	Can the raw key be accessed, e.g. in tests?
Parameters	Are parameters for choosing comment, table, bundle available?

• ⚠️ Some types can and need to be converted into String before using them in UIKit, or SwiftUI
  • String(localized resource: LocalizedStringValue)
  • String(localized resource: LocalizedStringResource)

String Interpolation

All "SC compatible" types also support String interpolation to insert dynamic values into the localizable key.

For simplification these examples are not added to the project. The following code would result in a string catalog entry: Hello %@

func greeting(with name: String) -> LocalizedStringResource {
    LocalizedStringResource(
        "Hello \(name)",
        comment: "A short greeting with a name parameter"
    )
}

App vs. Preview

App	SwiftUI preview