Use the Entire Screen

Published by @SoNiceInfo at 6/24/2020

There are 2 ways to use the entire screen.

Expand frame maxWidth and maxHeight of VStack to infinity
Apply .edgesIgnoringSafeArea(.all) to ZStack

Expand `frame` of `VStack`

Setting .infinity of frame, the view is expanded to the entire screen remaining the safe area.
Here is the example code applied infinity to frame.
backgound() is colored to make it easier to understand.

//
//  ContentView.swift
//

import SwiftUI

struct ContentView: View {
    @State var name: String = ""

    var body: some View {
        VStack {
            Spacer()
            Text("Result: ") + Text(name)
            TextField("Placeholder", text: $name)
                .padding()
                .border(Color.green, width: CGFloat(2))
            Spacer()
        }
        // ここが大事
        .frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .topLeading)
        .background(Color.yellow)
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

Use the entire screen remaining the safe area.

Apply `.edgesIgnoringSafeArea(.all)` to `ZStack`

Applying .edgesIgnoringSafeArea(.all), the view is expanded ignoring the safe area.
In ZStack, the first View is at the bottom, and the second View is at the top.

Make the background yellow to make the effect easier to see.

//
//  ContentView.swift
//

import SwiftUI

struct ContentView: View {
    @State var name: String = ""

    var body: some View {
        ZStack {
            Color.yellow
                .opacity(0.4)
                // ここが大事
                .edgesIgnoringSafeArea(.all)

            VStack {
                Text("Result: ") + Text(name)
                TextField("Placeholder", text: $name)
                    .padding()
                    .border(Color.green, width: CGFloat(2))
            }
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}