ios 使用 NavigationViewController swift 呈现 ViewController

presenting ViewController with NavigationViewController swift

提问by Yury Alexandrov

I have system "NavigationViewController -> MyViewController", and I programmatically want to present MyViewController inside a third view controller. The problem is that I don't have navigation bar in MyViewController after presenting it. Can you help me?

我有系统“NavigationViewController -> MyViewController”，我想以编程方式在第三个视图控制器中显示 MyViewController。问题是我在呈现后在 MyViewController 中没有导航栏。你能帮助我吗？

var VC1 = self.storyboard.instantiateViewControllerWithIdentifier("MyViewController") as ViewController
self.presentViewController(VC1, animated:true, completion: nil)

回答by stefandouganhyde

Calling presentViewControllerpresents the view controller modally, outside the existing navigation stack; it is not contained by your UINavigationController or any other. If you want your new view controller to have a navigation bar, you have two main options:

调用在现有导航堆栈之外以模态方式presentViewController呈现视图控制器；它不包含在您的 UINavigationController 或任何其他控件中。如果你想让你的新视图控制器有一个导航栏，你有两个主要选择：

Option 1. Push the new view controller onto your existing navigation stack, rather than presenting it modally:

选项 1. 将新的视图控制器推送到您现有的导航堆栈上，而不是以模态方式呈现：

let VC1 = self.storyboard!.instantiateViewControllerWithIdentifier("MyViewController") as! ViewController
self.navigationController!.pushViewController(VC1, animated: true)

Option 2. Embed your new view controller into a new navigation controller and present the new navigation controller modally:

选项 2. 将新的视图控制器嵌入到新的导航控制器中，并以模态方式呈现新的导航控制器：

let VC1 = self.storyboard!.instantiateViewControllerWithIdentifier("MyViewController") as! ViewController
let navController = UINavigationController(rootViewController: VC1) // Creating a navigation controller with VC1 at the root of the navigation stack.
self.present(navController, animated:true, completion: nil)

Bear in mind that this option won't automatically include a "back" button. You'll have to build in a close mechanism yourself.

请记住，此选项不会自动包含“后退”按钮。你必须自己建立一个封闭的机制。

Which one is best for you is a human interface design question, but it's normally clear what makes the most sense.

哪一个最适合你是一个人机界面设计问题，但通常很清楚什么最有意义。

回答by Maksim Kniazev

SWIFT 3

斯威夫特 3

let VC1 = self.storyboard!.instantiateViewController(withIdentifier: "MyViewController") as! MyViewController
let navController = UINavigationController(rootViewController: VC1)
self.present(navController, animated:true, completion: nil)

回答by Vinod Joshi

My navigation bar was not showing, so I have used the following method in Swift 2 iOS 9

我的导航栏没有显示，所以我在 Swift 2 iOS 9 中使用了以下方法

let viewController = self.storyboard?.instantiateViewControllerWithIdentifier("Dashboard") as! Dashboard

// Creating a navigation controller with viewController at the root of the navigation stack.
let navController = UINavigationController(rootViewController: viewController)
self.presentViewController(navController, animated:true, completion: nil)

回答by Honey

The accepted answer is great. This is not answer, but just an illustration of the issue.

接受的答案很棒。这不是答案，而只是问题的说明。

I present a viewController like this:

我提出了一个这样的视图控制器：

inside vc1:

在 vc1 内：

func showVC2() {
    if let navController = self.navigationController{
        navController.present(vc2, animated: true)
    }
}

inside vc2:

在 vc2 里面：

func returnFromVC2() {
    if let navController = self.navigationController {
        navController.popViewController(animated: true)
    }else{
        print("navigationController is nil") <-- I was reaching here!
    }
}

As 'stefandouganhyde' has said: "it is not contained by your UINavigationController or any other"

正如“stefandouganhyde”所说：“它不包含在您的 UINavigationController 或任何其他控件中”

new solution:

新解决方案：

func returnFromVC2() {
    dismiss(animated: true, completion: nil)
}

回答by Atka

I used an extension to UIViewController and a struct to make sure that my current view is presented from the favourites

我使用了 UIViewController 的扩展和结构来确保我当前的视图是从收藏夹中显示的

1.Struct for a global Bool

1.Struct 全局 Bool

struct PresentedFromFavourites {
static var comingFromFav = false}

2.UIVeiwController extension: presented modally as in the second option by "stefandouganhyde - Option 2 " and solving the back

2.UIVeiwController 扩展：在“stefandouganhyde - Option 2”的第二个选项中模态呈现并解决后面

extension UIViewController {
func returnToFavourites()
{
    // you return to the storyboard wanted by changing the name
    let storyBoard : UIStoryboard = UIStoryboard(name: "Main", bundle:nil)
    let mainNavigationController = storyBoard.instantiateViewController(withIdentifier: "HomeNav") as! UINavigationController
    // Set animated to false
    let favViewController = storyBoard.instantiateViewController(withIdentifier: "Favourites")
    self.present(mainNavigationController, animated: false, completion: {
        mainNavigationController.pushViewController(favViewController, animated: false)
    })

}
// call this function in viewDidLoad()
// 
func addBackToFavouritesButton()
{
    if PresentedFromFavourites.comingFromFav
    {
        //Create a button
        // I found this good for most size classes
        let buttonHeight = (self.navigationController?.navigationBar.frame.size.height)! - 15
        let rect = CGRect(x: 2, y: 8, width: buttonHeight, height: buttonHeight)
        let aButton = UIButton(frame: rect)
        // Down a back arrow image from icon8 for free and add it to your image assets  
        aButton.setImage(#imageLiteral(resourceName: "backArrow"), for: .normal)
        aButton.backgroundColor = UIColor.clear
        aButton.addTarget(self, action:#selector(self.returnToFavourites), for: .touchUpInside)
        self.navigationController?.navigationBar.addSubview(aButton)
        PresentedFromFavourites.comingFromFav = false
    }

}}