How to create a toggle switch

SwiftUI’s toggle lets users move between true and false states, just like UISwitch in UIKit.

For example, we could create a toggle that either shows a message or not depending on whether the toggle is enabled or not, but of course we don’t want to have to track the state of the toggle by hand – we want SwiftUI to do that for us.

Instead we should define a @State Boolean property that will be used to store the current value of our toggle. We can then use that to show or hide other views as needed.

For example:

struct ContentView: View {
    @State private var showGreeting = true

    var body: some View {
        VStack {
            Toggle(isOn: $showGreeting) {
                Text("Show welcome message")
            }.padding()

            if showGreeting {
                Text("Hello World!")
            }
        }
    }
}

I’ve made that code so that a text view is returned only when showGreeting is true, which means the VStack will decrease in size when showGreeting is false – it doesn’t have a second view in its stack.

Note: When using @State Apple recommends you mark your property with the private access control modifier, to make it clear this piece of state is owned by the local view and not used elsewhere.