在Swift中关闭并呈现视图控制器

Question

嗨,我正在尝试提供一个viewcontroller并解除我当前的模态视图,但这段代码不起作用

self.dismissViewControllerAnimated(true, completion: {
    let vc = self.storyboard?.instantiateViewControllerWithIdentifier("OrderViewController")
    self.presentViewController(vc!, animated: true, completion: nil)
})

反之亦然,在presentviewcontroller的完成块上也不起作用

编辑:更换vc!自我

Answer 1

你必须获得呈现self(当前ViewController)的viewController.如果该视图控制器是rootViewController,您可以使用如下,如果不是该查询它基于您查看控制器层次结构.

if let vc3 = self.storyboard?.instantiateViewController(withIdentifier: "vc3") as? ViewController3 {
    let appDelegate = UIApplication.shared.delegate as! AppDelegate
    appDelegate.window?.rootViewController!.present(vc3, animated: true, completion: nil)
}

Answer 2

你不能这样做,因为当UIViewController A调用UIViewController B并且第一个控制器被解除时,两个控制器都是零.

你需要有一个UIViewController作为基础,在这种情况下,MainViewController是基础.您需要使用协议来调用控制器之间的导航.

你可以使用协议,比如说如下: -

在你的viewController设置协议中:

    protocol FirstViewControllerProtocol {
    func dismissViewController()
}

class FirstViewController: UIViewController {
    var delegate:FirstViewControllerProtocol!

    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 goBack(sender: AnyObject) {
        self.dismissViewControllerAnimated(true) { 
            self.delegate!.dismissViewController()
        }
    }

现在在主视图控制器中

class MainViewController: UIViewController, FirstViewControllerProtocol {

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 goToFirstViewController(sender: AnyObject) {
    let viewController = self.storyboard?.instantiateViewControllerWithIdentifier(String(FirstViewController)) as! FirstViewController
    viewController.delegate = self
    self.presentViewController(viewController, animated: true, completion: nil)
}



//MARK: Protocol
func dismissViewController() {
    if let viewController = self.storyboard?.instantiateViewControllerWithIdentifier(String(SecondViewController)){
        self.presentViewController(viewController, animated: true, completion: nil)
    }
}

故事板的代码示例:

Answer 3

我认为你的代码中有一个错误,'self'应该是呈现视图控制器来呈现'vc',而不是'vc'它自己

你的代码

self.dismissViewControllerAnimated(true, completion: {
                let vc = self.storyboard?.instantiateViewControllerWithIdentifier("OrderViewController")
                vc!.presentViewController(vc!, animated: true, completion: nil)
            })

试试这个

self.dismissViewControllerAnimated(true, completion: {
                let vc = self.storyboard?.instantiateViewControllerWithIdentifier("OrderViewController")
                self.presentViewController(vc!, animated: true, completion: nil)
            })

希望这是有帮助的