override func navigate(to step: AppStep) -> StepAction { switch step { case .showFirstViewController(let animated): let firstViewController = DocumentBrowserViewController(forOpeningFilesWithContentTypes: ["two", "one"]) return .push(firstViewController) case .showSecondViewController(let animated): let secondViewController = DocumentBrowserViewController(forOpeningFilesWithContentTypes: ["hone", "two"]) return .push(secondViewController) default: return .none } }