SwinjectStoryboard中的storyboardInitCompleted（）不会调用VC resolve

Question

StoryboardInitCompleted块完成时，SwinjectStoryboard解析nil对象。这就是为什么ViewController中的viewModel: ViewModelProtocol!对象为nil的原因，它使我的应用程序始终在Swift 4.2中崩溃。

MainContainer：

import Swinject

class MainContainer {
  static let sharedContainer = MainContainer()
  let container = Container()

  private init() {
    setupContainers()
  }

  private func setupContainers() {
    Container.loggingFunction = nil
    container.register(UnsplashService.self){ _ in UnsplashService()}.inObjectScope(.container)
    container.register(UnsplashManagerProtocol.self){ r in UnsplashDataFetcher(with: r.resolve(UnsplashService.self)!)}.inObjectScope(.container)
    container.register(ViewModelProtocol.self){ r in ViewModel(withClient: r.resolve(UnsplashManagerProtocol.self)!)}.inObjectScope(.container)
  }
}

SwinjectStoryboard：

import Swinject
import SwinjectStoryboard

extension SwinjectStoryboard {
  @objc class func setup() {
    let mainContainer = MainContainer.sharedContainer.container

    defaultContainer.storyboardInitCompleted(PhotosCollectionViewController.self) { _, controller in
      controller.viewModel = mainContainer.resolve(ViewModelProtocol.self)!
    }
  }
}

PhotosCollectionViewController：

class PhotosCollectionViewController: UICollectionViewController {

  var viewModel: ViewModelProtocol!

  ...
}