Update SignInView.swift

[movsianikov]

Fix issue with declaration of GoogleSignInButtonViewModel variable. Switching to @StateObject from @ObservedObject allows to customize the button using constructor, otherwise - the customization doesn't work.

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[mdmathias]

Can you clarify what you mean by "allows to customize the button using constructor, otherwise - the customization doesn't work?" I am not sure what you're fixing.

[movsianikov]

Can you clarify what you mean by "allows to customize the button using constructor, otherwise - the customization doesn't work?" I am not sure what you're fixing.

Hi @mdmathias , of course! Here you go:

1. With the current approach this customization does NOT work:
   @ObservedObject private var vm = GoogleSignInButtonViewModel(scheme: .dark, style: .wide, state: .normal)
2. In order to make it work (workaround), I've customized it in the init() method like this:

    init() {
        vm.style = .wide
        vm.scheme = .dark
    }

3. But the correct way, since the instance of the GoogleSignInButtonViewModel created in the SignInView, would be to declare it as @StateObject, then the customization will work fine without init() method:
   @ObservedObject private var vm = GoogleSignInButtonViewModel(scheme: .dark, style: .wide, state: .normal)

Please let me know if you have any questions, comments, or concerns.

Thank you!

Best regards,
MAKSYM OVSIANIKOV

[mdmathias]

@movsianikov I'm sorry! I still don't understand what you mean by the "customization" not working. In SignInView.swift, if you create the vm with a different scheme (e.g., .dark), then the button will be drawn with the dark blue background.

struct SignInView: View {
  @EnvironmentObject var authViewModel: AuthenticationViewModel
  @ObservedObject var vm = GoogleSignInButtonViewModel(scheme: .dark)
...