Custom back button in the NavigateAndLoad case study

Related Projects Swift Composable Architecture
1

I'm struggling to figure out how to add a custom back button to a view, while following the NavigateAndLoad case study example.

when I add
@Environment(\.presentationMode) var mode
to the CounterView, the IfLetStore breaks in the parent view.

NavigationLink(
              destination: IfLetStore(
                self.store.scope(
                  state: \.selection?.value,
                  action: LoadThenNavigateListAction.counter
                ),
                then: CounterView.init(store:mode:)
              ),
              tag: row.id,
              selection: viewStore.binding(
                get: \.selection?.id,
                send: LoadThenNavigateListAction.setNavigation(selection:)
              )
            )

The error is:
Cannot convert value of type '(Store<CounterState, CounterAction>, Environment<Binding>) -> CounterView' to expected argument type '(Store<CounterState, CounterAction>) -> CounterView'

Can anyone guide me on how to rewrite the IfLetStore statement, so that it can initialize the CounterView while it includes an environment variable?

2

When you add the environment value presentationMode to a view it becomes apart of the initializer, but you are not meant to actually pass it along. It has a default value.

So this means you must explicitly open the closure for the then view in order to pass along just the store:

then: { CounterView(store: $0) }
3

Amazing, thank you so much!

4

Alternatively, you should just mark the environment property as private (it should be private anyway) and it shouldn’t become part of the initialiser.

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