有没有办法让导航栏跨多个视图？

Question

所以我有 2 个视图，当我点击“转到第二个视图”时，导航栏应该是固定的，唯一应该移动的部分是导航栏下方的视图。 swift 是否有可能通过情节提要或以编程方式允许此操作？

Answer 1

是的。 有。

1. 创建PageViewController.swift并粘贴下面的代码

//
//  Copyright © 2018 fewlinesofcode.com All rights reserved.
//
import UIKit

class PageViewController: UIPageViewController {
    fileprivate(set) var currentPageIndex: Int = 0
    
    var pages = [UIViewController]()
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        if let firstViewController = page(at: currentPageIndex) {
            setViewControllers([firstViewController], direction: .forward, animated: false, completion: { completed in })
        }
    }
    
    func resetIndex() { currentPageIndex = 0 }
    
    func page(at index: Int) -> UIViewController? {
        guard index >= 0 && index < pages.count else { return nil }
        return pages[index]
    }
}

extension PageViewController: UIPageViewControllerDataSource {
    func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? {
        guard let pageIndex = pages.index(of: viewController), currentPageIndex != 0 else {
            return nil
        }
        currentPageIndex = pageIndex
        currentPageIndex -= 1
        return page(at: currentPageIndex)
    }
    
    func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController? {
        guard let pageIndex = pages.index(of: viewController) else {
            return nil
        }
        currentPageIndex = pageIndex + 1
        
        if currentPageIndex == pages.count {
            return nil
        }
        return page(at: currentPageIndex)
    }
    
    func presentationCount(for pageViewController: UIPageViewController) -> Int {
        return pages.count
    }
    
    func presentationIndex(for pageViewController: UIPageViewController) -> Int {
        return currentPageIndex
    }
}

extension PageViewController {
    func showPrev(completion: ((Bool) -> Void)? = nil) {
        guard currentPageIndex > 0 else { return }
        currentPageIndex -= 1
        setViewControllers([pages[currentPageIndex]], direction: .reverse, animated: true, completion: completion)
    }
    
    func showNext(completion: ((Bool) -> Void)? = nil) {
        guard currentPageIndex < pages.count - 1 else { return }
        currentPageIndex += 1
        setViewControllers([pages[currentPageIndex]], direction: .forward, animated: true, completion: completion)
    }
}

2. 像下面的示例一样对其进行子类化：

class ViewController: PageViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        
        setupChildViewControllers()
    }
    
    private func setupChildViewControllers() {
        let vc1 = <Instantiate your VC 1>
        let vc2 = <Instantiate your VC 2>
        
        pages = [
            vc1, vc2
        ]
    }
}

3.设置导航

只需在UINavigationController嵌入ViewController 。

Answer 2

每个视图控制器都有自己的导航栏执行。 唯一可行的方法是不要移动到另一个视图控制器，您可以创建 UIView 的子类，并在单击该按钮时通过将其添加到基本视图控制器的子视图来呈现一个新的 UIView。