Mastering SwiftUI’s FocusState

Photo by Stefan Cosma on Unsplash

When developing iOS apps using SwiftUI it is critical that focus is managed. That means we gain fine-grained control over which field is in focus at any given time, so long as we are using iOS 15 or later.

Here is an article about @FocusState, how is it can be used in any apps you might have brewing.

What is @FocusState?

@FocusState is a property wrapper in SwiftUI that allows developers to manage focus programmatically for input fields like TextField and SecureField. By binding the focus state of these components to a shared @FocusState property, you gain fine-grained control over which field is in focus at any given time.

Essentially FocusState is an alternative to UIKit’s becomeFirstResponder and gives similar functionality in a declarative world.

An Example

struct ContentView: View {
    @State private var firstName: String = ""
    @State private var lastName: String = ""
    @FocusState private var focusedField: Field?
    
    enum Field: Hashable {
        case firstName
        case lastName
    }

    var body: some View {
        Form {
            TextField("First Name", text: $firstName)
                .focused($focusedField, equals: .firstName)
                .submitLabel(.next)
                .onSubmit {…