如何解决如何从函数中获取更改后的视图控制器的值?
我的任务是为我的 OperationsService 创建一个“适配器”:
class OperationsService {
private var viewController: UIViewController
private let operationQueue = OperationQueue()
init(viewController: UIViewController) {
self.viewController = viewController
}
func getFriends() {
let request = Alamofire.request(...)
let getDataOperation = GetDataOperation(request: request)
operationQueue.addOperation(getDataOperation)
let parseDataOperation = ParseDataOperation<UserModel>()
parseDataOperation.addDependency(getDataOperation)
operationQueue.addOperation(parseDataOperation)
let reloadTableOperation = ReloadTableOperation<UserModel>(controller: viewController)
reloadTableOperation.addDependency(parseDataOperation)
OperationQueue.main.addOperation(reloadTableOperation)
}
我决定创建一个虚拟 VC 将它传递给我的 OperationsService:
class OperationsAdapter {
private var operationsService: OperationsService?
func getFriends(completion: @escaping ([UserModelItem]) -> Void) {
let dummyVC = FriendsViewController()
operationsService = OperationsService(viewController: dummyVC)
operationsService!.getFriends()
let friends = dummyVC.friends // friends == 0
completion(friends)
}
}
FriendsViewController 看起来像这样:
class FriendsViewController: UIViewController {
@IBOutlet weak var tableView: UITableView!
var friends: [UserModelItem] = []
private var operationsAdapter = OperationsAdapter()
override func viewDidLoad() {
super.viewDidLoad()
operationsAdapter.getFriends { [weak self] friends in
guard let self = self else { return }
self.friends = friends
self.tableView.reloadData()
}
但是我从 getFriends() 函数收到 0 个朋友,我不明白为什么。
我还认为您需要查看 ReloadTableOperation:
class ReloadTableOperation<T: Codable>: Operation {
private var controller: UIViewController?
init(controller: UIViewController?) {
self.controller = controller
}
override func main() {
guard
let parseDataOperation = dependencies.first as? ParseDataOperation<T>,let parsedData = parseDataOperation.outputData
else { return }
guard
let friendsViewController = controller as? FriendsViewController,let friends = parsedData as? [UserModelItem]
else { return }
friendsViewController.friends = friends // friends != 0
if friendsViewController.tableView != nil {
friendsViewController.tableView.reloadData()
}
}
}
在这个类中friendsViewController.friends不是0但是这个值没有传回来。
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。