performseguewithidentifier在一个viewDidLoad中工作但在另一个viewDidLoad中没有，使用＆＃34; Show＆＃34;塞格斯

Question

这是第一个viewDidLoad：

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    if ([[NSUserDefaults standardUserDefaults] objectForKey:@"Tutorial"]) {
        [self performSegueWithIdentifier:@"fromTutorialToWelcome" sender:self];
    }else{
        [self setupVc];
    }
}

这是第二个，在以下视图控制器中：

- (void)viewDidLoad {
    [super viewDidLoad];
    if ([[NSUserDefaults standardUserDefaults] objectForKey:@"loginTesting"]) { //This evaluates to true, I double and triple checked.

        [self performSegueWithIdentifier:@"fromWelcomeToEntryPoint" sender:self];
    }else{
        [self setupVc];
    }
}

两个segues都是显示 segues，那么为什么第二个不工作呢？

编辑：强调segue的类型，因为这不再是iOS5。

EDIT2：我想我没有正确解释我想做什么。我希望在不看第二个视图控制器的情况下显示第三个视图控制器。

Answer 1

当您从非运行状态打开应用程序时，每个视图仅加载到内存中一次。在第二个视图控制器中，将它从viewDidLoad移动到viewDidAppear。我相信它会解决你的问题。如果它没有，请告诉我，我会尝试调试它。

编辑：

这是我做的一个工作示例。

第一次： FirstViewController - ＆gt; SecondViewController - ＆gt; ThirdViewController

第二次： FirstViewController - ＆gt; ThirdViewController（没有看到SecondViewController！）

FirstViewController.swift：

import UIKit

class FirstViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    @IBAction func ToSecondPressed(sender: AnyObject) {

        if let skip = NSUserDefaults.standardUserDefaults().valueForKey("SkipSecond") as? Bool{

            let Third: ThirdViewController = UIStoryboard(name: "Main", bundle: NSBundle.mainBundle()).instantiateViewControllerWithIdentifier("Third") as! ThirdViewController

            UIApplication.sharedApplication().delegate?.window??.rootViewController = Third
        }

        else{

            let Second: SecondViewController = UIStoryboard(name: "Main", bundle: NSBundle.mainBundle()).instantiateViewControllerWithIdentifier("Second") as! SecondViewController

            NSUserDefaults.standardUserDefaults().setBool(true, forKey: "SkipSecond")
            UIApplication.sharedApplication().delegate?.window??.rootViewController = Second
        }

    }

}

SecondViewController.swift：

import UIKit

class SecondViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    @IBAction func ToThirdPressed(sender: AnyObject) {
        let Third = UIStoryboard(name: "Main", bundle: NSBundle.mainBundle()).instantiateViewControllerWithIdentifier("Third") as? ThirdViewController

        UIApplication.sharedApplication().delegate?.window??.rootViewController = Third
    }


}

ThirdViewController.swift：

import UIKit

class ThirdViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}