Example of aligning labels in SwiftUI.Form on macOS

FormDemoApp.swift

//
//  FormDemoApp.swift
//  FormDemo
//
//  Created by Marc Prud'hommeaux
//

import SwiftUI

@main
struct FormDemoApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

/// Alignment guide for aligning a text field in a `Form`.
/// Thanks for Jim Dovey  https://developer.apple.com/forums/thread/126268
extension HorizontalAlignment {
    private enum ControlAlignment: AlignmentID {
        static func defaultValue(in context: ViewDimensions) -> CGFloat {
            return context[HorizontalAlignment.center]
        }
    }
    
    static let controlAlignment = HorizontalAlignment(ControlAlignment.self)
}

public extension View {
    /// Attaches a label to this view for laying out in a `Form`
    /// - Parameter view: the label view to use
    /// - Returns: an `HStack` with an alignment guide for placing in a form
    func formLabel<V: View>(_ view: V) -> some View {
        HStack {
            view
            self
                .alignmentGuide(.controlAlignment) { $0[.leading] }
        }
        .alignmentGuide(.leading) { $0[.controlAlignment] }

    }
}

struct ContentView: View {
    var body: some View {
        Form {
            TextField("Text Field", value: .constant(""), formatter: NumberFormatter())
                .textFieldStyle(RoundedBorderTextFieldStyle())
                .formLabel(Text("Text Field"))

            Section() {
                Picker(selection: .constant(2), label: Text("Menu Picker"), content: {
                    Text("First").tag(1)
                    Text("Second").tag(2)
                })
                .pickerStyle(MenuPickerStyle())

                Picker(selection: .constant(2), label: Text("Segment Picker"), content: {
                    Label("First", systemImage: "1.circle.fill").tag(1)
                    Label("Second", systemImage: "2.circle.fill").tag(2)
                })
                .labelStyle(IconOnlyLabelStyle())
                .pickerStyle(SegmentedPickerStyle())

                Picker(selection: .constant(2), label: Text("Radio Picker"), content: {
                    Text("One").tag(1)
                    Text("Two").tag(2)
                })
                .pickerStyle(InlinePickerStyle())
            }

            Slider(value: .constant(0.5), in: 0...1) {
                Label("Slider", systemImage: "bolt")
            }
            .labelStyle(TitleOnlyLabelStyle())

            Stepper(
                onIncrement: { },
                onDecrement: {  },
                onEditingChanged: { changed in },
                label: {
                    Text("Stepper")
                })


            Section() {
                Toggle("Toggle A", isOn: .constant(true))
                    .toggleStyle(SwitchToggleStyle())
            }

        }
        .padding()
        .frame(width: 270)
    }
}

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