refactor: the way providers are initialized. AnyView is used to render provider buttons.

[russellwheatley]

I cannot find a way to make it work where the Buttons are not type erased.

We have types unknown to core auth package and we're trying to render unknown button types in core auth package. How can we render without using type erasure?

If there is a clever way of doing this, I would love to know.

[morganchen12]

I think we should just make the button views any View since they're small views that aren't nested and we can't pass type data for these particular views up from subdependencies to the root Auth module.

[peterfriese]

Did you try returning some View? You might need to annotate the function with @ViewBuilder

[russellwheatley]

cannot have some View as return type on protocol apparently. Get Xcode compiler error: 'some' type cannot be the return type of a protocol requirement; did you mean to add an associated type?

[peterfriese]

I put together something that might help: https://gist.github.com/peterfriese/d9745f366fb4f857daf077e93b1eb01f

import SwiftUI

protocol AuthProvider: Identifiable {
  var id: String { get }
  associatedtype ButtonType: View
  var authButtonView: Self.ButtonType { get }
}

protocol FooProviderProtocol: AuthProvider {
  func doFoo()
}

struct FooProviderImpl1: FooProviderProtocol {
  var id: String = "FooProviderImpl1"

  func doFoo() {
    print("1")
  }

  var authButtonView: some View {
    Text("1")
  }
}

struct FooProviderImpl2: FooProviderProtocol {
  var id: String = "FooProviderImpl2"

  func doFoo() {
    print("2")
  }

  var authButtonView: some View {
    Text("2")
      .background(Color.red)
  }
}

protocol BarProviderProtocol: AuthProvider {
  func doBar()
}

struct BarProviderImpl1: BarProviderProtocol {
  var id: String = "BarProviderImpl1"
  
  func doBar() {
    print("1")
  }
  
  var authButtonView: some View {
    Text("1")
  }
}

struct BarProviderImpl2: BarProviderProtocol {
  var id: String = "BarProviderImpl2"
  
  func doBar() {
    print("2")
  }
  
  var authButtonView: some View {
    Text("2")
      .background(Color.red)
  }
}


struct ContentView<Provider: AuthProvider>: View {
  var provider: Provider
  var body: some View {
    VStack {
      provider.authButtonView
    }
  }
}

#Preview {
  ContentView(provider: BarProviderImpl2())
}

[russellwheatley]

I've responded in the other PR: #1250

[morganchen12]

Ok to use AnyView since there's no good way to get concrete view types from a module that may or may not be included. We can revisit this decision if it causes noticeable performance issues.