我已经看过 StackOverFlow。现有的问题似乎对我没有帮助。
我正在使用 ParseUI 来处理用户登录功能,但在注册新用户时遇到了问题。
问题:当用户去注册并点击“注册”按钮时,会出现此错误并且没有发生转义:
<Warning: Attempt to present edus.ClassEntryViewController: 0x7f8800ceb0a0> on <PFLogInViewController: 0x7f8800c2f520> whose view is not in the window hierarchy!
我不知道如何解决这个问题。相关代码如下:
import UIKit
import Parse
import Bolts
import ParseUI
import FBSDKCoreKit
import ParseFacebookUtils
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
var parseLoginHelper: ParseLoginHelper!
override init() {
super.init()
parseLoginHelper = ParseLoginHelper {[unowned self] user, error in
// Initialize the ParseLoginHelper with a callback
if let error = error {
// 1
ErrorHandling.defaultErrorHandler(error)
} else if let user = user {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
//creation
let classNavEntry = storyboard.instantiateViewControllerWithIdentifier("ClassNavEntry") as! UIViewController
//presentation. PROBLEM HERE??
self.window?.rootViewController!.presentViewController(classNavEntry, animated:true, completion:nil)
}
}
}
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
let user = PFUser.currentUser()
let startViewController: UIViewController;
if (user != nil) {
// 3
// if we have a user, set the ClassNavEntry to be the initial View Controller
let storyboard = UIStoryboard(name: "Main", bundle: nil)
//problem may arise here
startViewController =
storyboard.instantiateViewControllerWithIdentifier("ClassNavEntry") as! UINavigationController
} else {
// 4
// Otherwise set the LoginViewController to be the first
let loginViewController = PFLogInViewController()
loginViewController.fields = .UsernameAndPassword | .LogInButton | .SignUpButton | .PasswordForgotten | .Facebook
loginViewController.delegate = parseLoginHelper
loginViewController.signUpController?.delegate = parseLoginHelper
startViewController = loginViewController
}
// 5
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
self.window?.rootViewController = startViewController;
self.window?.makeKeyAndVisible()
更新:我知道是什么导致了这个问题,还在想办法解决它。
问题是有两个视图控制器:loginViewController 和 SignupViewController。我在这里指定根视图控制器是 loginViewController:
loginViewController.delegate = parseLoginHelper
loginViewController.signUpController?.delegate = parseLoginHelper
startViewController = loginViewController
}
// 5
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
//THIS SPECIFIES ROOTVIEW TO BE LOGINVIEWCONTROLLER
self.window?.rootViewController = startViewController
self.window?.makeKeyAndVisible()
所以我还需要能够在 SignUpViewController 上调用 parseHelper ......