robb/atrandom

Fixed Seeds

By default, different instances of the same View or ViewModifier generate unique @Random values. To ensure consistency, you can provide a custom seed via the property wrapper’s projectedValue's seed value.

For example, assigning a model’s hashValue to $greeting.seed ensures stability when the view gets recreated, say in a LazyVStack.

struct Cell: View {
    @Random(in: "Hello", "Bonjour", "Willkommen") var greeting

    var model: Model

    init(model: Model) {
        self.model = model
        $greeting.seed = model.hashValue
    }

    var body: some View {
      // The same `model` will get the same `greeting`, every time.
      Text("\(greeting), \(model.name)!")
    }
}

This way, each Cell instance with the same model will always produce the same greeting.

[!IMPORTANT] Some Swift types, like String, generate different hashValues across app launches. For values that persist across launches, use a stable identifier, such as a user ID.

Package Metadata

Repository: robb/atrandom

Default branch: main

README: README.md