致命错误：在自定义navigationcontroller中使用未实现的初始化程序

I'm creating a custom navigation controller. I have something like this:

我正在创建一个自定义导航控制器。我有这样的事情:

public class CustomNavigationController: UINavigationController {

    // MARK: - Life Cycle

    override init(rootViewController: UIViewController) {
        super.init(rootViewController: rootViewController)

        delegate = self
    }

    required public init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        delegate = self
    }
}

I wanted to test this out so I created a CustomNavigationController like this:

我想测试一下,所以我创建了一个CustomNavigationController,如下所示:

CustomNavigationController(rootViewController: ViewController())

When I run the app I get this:

当我运行应用程序时,我得到了这个:

fatal error: use of unimplemented initializer 'init(nibName:bundle:)' for class 'TestApp.CustomNavigationController'

I don't see the problem, can anyone help me out?

我没有看到问题,任何人都可以帮助我吗?

2 个解决方案

#1

UINavigationController's implementation of init(rootViewController:) probably calls self.init(nibName:bundle:) which you haven't implemented so it throws the error.

UINavigationController的init(rootViewController :)实现可能会调用你没有实现的self.init(nibName:bundle :),因此它会抛出错误。

You should override init(nibName:bundle) in addition to the initializers you already override. init(nibName:bundle:) is a designated initializer while init(rootViewController:) is a convenience initializer.

除了已经覆盖的初始值设定项之外,还应覆盖init(nibName:bundle)。 init(nibName:bundle :)是指定的初始化程序,而init(rootViewController :)是一个便利初始化程序。

#2

While using custom navigation controller, we need to use override initproperty of NavigationController as-

使用自定义导航控制器时,我们需要使用NavigationController的覆盖initproperty-

class CustomNavigationController: UINavigationController {

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

    }
    override init(rootViewController: UIViewController) {
        super.init(rootViewController: rootViewController)
    }
    override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
        super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
    }

}

& in Appdelegate class use -

&在Appdelegate类中使用 -

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        self.window = UIWindow(frame: UIScreen.main.bounds)
        let vc = ViewController(nibName: "ViewController", bundle: nil)
        let navi =  CustomNavigationController(rootViewController: vc)
        window?.backgroundColor = .white
        window?.rootViewController = navi
        window?.makeKeyAndVisible()
        return true
    }
}

As per Apple Document - To simplify the relationships between designated and convenience initializers, Swift applies the following three rules for delegation calls between initializers:

根据Apple文档 - 为了简化指定和便利初始化程序之间的关系,Swift对初始化程序之间的委托调用应用以下三个规则:

Rule 1 A designated initializer must call a designated initializer from its immediate superclass.

规则1指定的初始化程序必须从其直接超类中调用指定的初始化程序。

Rule 2 A convenience initializer must call another initializer from the same class.

规则2便捷初始化程序必须从同一个类调用另一个初始化程序。

Rule 3 A convenience initializer must ultimately call a designated initializer.

规则3便利初始化器必须最终调用指定的初始化器。

A simple way to remember this is:-

记住这一点的一个简单方法是: -

#1