為什么我的 iOS11 導航控制器不起作用

Question

我只想顯示一個大標題。
我的ViewController.swift看起來像：

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        self.view.backgroundColor = UIColor.white

        title = "Hello world"
        self.navigationController?.navigationBar.prefersLargeTitles = true
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }

}

但它不起作用。

Answer 1

  let navigationBar = UINavigationBar(frame: CGRect(x: 0, y: 0, width: self.view.frame.size.width, height: 60))
        navigationBar.backgroundColor = UIColor(red: 46.0/255.0, green: 145.0/255.0, blue: 245.0/255.0, alpha: 1.0)
        
        self.navigationItem.title = "Add Title"
        self.view .addSubview(navigationBar)
    if #available(iOS 11.0, *) {
        self.navigationController?.navigationBar.prefersLargeTitles = true
        self.navigationItem.largeTitleDisplayMode = .always
    } else {
        // Fallback on earlier versions
    }

Answer 2

顯示在導航欄，你需要做出大標題largeTitleDisplayMode .always添加下面的代碼行到您viewDidLoad也不要忘記檢查ios11或不

   title = "Hello world"

   if #available(iOS 11.0, *) {
        self.navigationController?.navigationBar.prefersLargeTitles = true
        self.navigationItem.largeTitleDisplayMode = .always
    }

並且您的UIViewController應該有一個UINavigationController如果您的 UIViewController 未嵌入 UINavigationController 中，請執行以下步驟

打開你的故事板 -> 選擇你的視圖控制器 -> 編輯器 -> 嵌入 -> NavigationController

Answer 3

首先，確保您的ViewController位於UINavigationController 。

繼續檢查IOS 11

title = "Title
if #available(iOS 11.0, *) {
    self.navigationController?.navigationBar.prefersLargeTitles = true
    self.navigationItem.largeTitleDisplayMode = .always

} else { ... }

Answer 4

您的問題是，您需要在導航控制器中添加您的視圖控制器

window = UIWindow(frame: UIScreen.main.bounds)
let mainController = ViewController()
let navigationController = UINavigationController(rootViewController: mainController)
self.window?.rootViewController = navigationController
self.window?.makeKeyAndVisible()