Two column NavigationView

November 13, 2022

---

A two column NavigationView creates a sidebar with a list of items and a content view. In the example shown below, selecting an item in the sidebar will change the content view. An @AppStorage property is used to remember the selected item.

import SwiftUI

struct ViewA: View {
    var body: some View {
        Text("View A 🍎").font(.title)
    }
}

struct ViewB: View {
    var body: some View {
        Text("View B 🥝").font(.title)
    }
}

struct ViewC: View {
    var body: some View {
        Text("View C 🍑").font(.title)
    }
}

struct ContentView: View {
    @AppStorage("savedSelection") private var savedSelection: String?

    var body: some View {
        NavigationView {
            List {
                NavigationLink("View A", tag: "A", selection: $savedSelection, destination: { ViewA() })
                NavigationLink("View B", tag: "B", selection: $savedSelection, destination: { ViewB() })
                NavigationLink("View C", tag: "C", selection: $savedSelection, destination: { ViewC() })
            }
            .frame(minWidth: 150)
            .listStyle(SidebarListStyle())
            Text("No sidebar item selected.")
        }
        .frame(width: 500, height: 300)
        .toolbar {
            ToolbarItem(placement: .navigation) {
                Button {
                    NSApp.sendAction(#selector(NSSplitViewController.toggleSidebar(_:)), to: nil, from: nil)
                } label: {
                    Image(systemName: "sidebar.left").help("Toggle sidebar")
                }
            }
        }
    }
}

Fill content view

To fill the entire content view, set the frame's max width and max height to infinity. This is demonstarated by the red and orange views shown below.

import SwiftUI

struct RedView: View {
    var body: some View {
        VStack {
            Text("Red View").font(.title)
            Text("🍎").font(.title)
        }
        .navigationTitle("Red View")
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(.red)
    }
}

struct OrangeView: View {
    var body: some View {
        VStack {
            Text("Orange View").font(.title)
            Text("🍊").font(.title)
        }
        .navigationTitle("Orange View")
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(.orange)
    }
}

struct ContentView: View {
    @AppStorage("savedSelection") private var savedSelection: String?

    var body: some View {
        NavigationView {
            List {
                NavigationLink("Red View", tag: "red", selection: $savedSelection, destination: { RedView() })
                NavigationLink("Orange View", tag: "orange", selection: $savedSelection, destination: { OrangeView() })
            }
            .frame(minWidth: 150)
            .listStyle(SidebarListStyle())

            Text("No sidebar item selected.")
        }
        .toolbar {
            ToolbarItem(placement: .navigation) {
                Button {
                    NSApp.sendAction(#selector(NSSplitViewController.toggleSidebar(_:)), to: nil, from: nil)
                } label: {
                    Image(systemName: "sidebar.left").help("Toggle sidebar")
                }
            }
        }
        .frame(width: 500, height: 300)
    }
}