19.3 The DemoProjectApp.swift File

The DemoProjectApp.swift file contains the declaration for the App object as described in the chapter entitled “SwiftUI Architecture” and will read as follows:

import SwiftUI

 

@main

struct DemoProjectApp: App {

    var body: some Scene {

        WindowGroup {

            ContentView()

        }

    }

}

As implemented, the declaration returns a Scene consisting of a WindowGroup containing the View defined in the ContentView.swift file. Note that the declaration is prefixed with @main. This indicates to SwiftUI that this is the entry point for the app when it is launched on a device.