Multiple sheets in SwiftUI

Multiple sheets in SwiftUI.md

This gist accompanies a blog post on Masilotti.com, How to manage multiple sheets in SwiftUI.

SettingsSheet.swift

class SettingsSheet: SheetState<SettingsSheet.State> {
    enum State {
        case attributions
        case email
        case feedback
        case instructions
        case licenseAgreement
        case privacyPolicy
    }
}

SettingsView.swift

struct SettingsView: View {
    @ObservedObject var sheet = SettingsSheet()

    var body: some View {
        VStack {
            Button("Attributions") { self.sheet.state = .attributions }
            Button("Email") { self.sheet.state = .email }
            Button("Feedback") { self.sheet.state = .feedback }
            Button("Instructions") { self.sheet.state = .instructions }
            Button("License Agreement") { self.sheet.state = .licenseAgreement }
            Button("Privacy Policy") { self.sheet.state = .privacyPolicy }
        }
        .sheet(isPresented: $sheet.isShowing, content: sheetContent)
    }

    @ViewBuilder
    private func sheetContent() -> some View {
        if sheet.state == .attributions {
            AttributionsView()
        } else if sheet.state == .email {
            EmailView()
        } else if sheet.state == .feedback {
            FeedbackView()
        } else if self.sheet.state == .instructions {
            InstructionsView()
        } else if self.sheet.state == .licenseAgreement {
            WebView(url: Policy.licenseURL)
        } else if self.sheet.state == .privacyPolicy {
            WebView(url: Policy.privacyURL)
        } else {
            EmptyView()
        }
    }
}

SheetState.swift

import Combine

class SheetState<State>: ObservableObject {
    @Published var isShowing = false
    @Published var state: State? {
        didSet { isShowing = state != nil }
    }
}

well written post/examples!

also I guess in the buttons you were mean to write

Button("Attributions") { self.sheet.state = .attributions }

Thanks @fespinoza.

You're correct, I updated the gist. Great catch!

I like your solution. How would you best implement a “Done” button inside the sheet? Pass $sheet.isShowing as Binding to the SheetView?

Exactly, @UlricusR! I'm doing the same for a confirmation button in a form-style sheet.

As I still had issues with conflicting Bindings to other Observable Objects with your final and your pre-final solution (the one without the SheetState class), I posted this on StackOverflow with a - in my eyes - very elegant solution, as you can even get rid of the SheetState class this way:

https://stackoverflow.com/questions/64139912/swiftui-state-property-is-not-updated

To close the sheet, I followed this post:

https://daddycoding.com/2020/03/01/swiftui-sheet-modals/

At the end, I combined your solution with the other two. Thanks again!

Very nice! Do you have a version for iOS 13?

Well, the App I use it for has target iOS 13.5 and above, so yes, it should work for iOS 13. You can see it in action e.g. in FoodList.swift in my repo https://github.com/UlricusR/iOS-EasyFPU