Entry Macro (SwiftUI)

The @Entry macro declares a custom environment value in one line, replacing the EnvironmentKey type plus the getter and setter extension. It also works for focused, container, and transaction values, and it back-deploys to earlier OS versions.

Before and After

The manual pattern needs a key type with a defaultValue and a computed property on EnvironmentValues, repeated for every value you share.

struct UserStateEnvironmentKey: EnvironmentKey {
  static var defaultValue: UserState = .new
}

extension EnvironmentValues {
  public var userState: UserState {
    get { self[UserStateEnvironmentKey.self] }
    set { self[UserStateEnvironmentKey.self] = newValue }
  }
}

With the macro, the default value comes from the initializer:

extension EnvironmentValues {
  @Entry var userState = UserState.new
}

Using the Value

The macro generates the key path, so injection and reading look exactly like any built-in environment value.

@main
struct MyApp: App {
  @State var userState = UserState.new

  var body: some Scene {
    WindowGroup {
      ContentView()
        .environment(\.userState, userState)
    }
  }
}

Focused Values

The same macro replaces FocusedValueKey boilerplate. The one difference: the property must be optional, because a focused value only exists while a view is focused.

extension FocusedValues {
  @Entry var noteValue: String?
}