UIPageView 显示具有 if 条件的页面

Question

在我的应用程序中，我使用 UIPageViewController 将多个视图控制器显示为页面。 这个想法是根据系统日期呈现一个视图控制器。 我通过这段代码实现了这一点，并且效果很好：

    let Today = UserDefaults.standard.string(forKey: "nextDAY")!

    print(Today)

    //24.10.2021
    
    let vc1 = self.storyboard?.instantiateViewController(withIdentifier: "page1")as! TestPageVC
    vc1.WordTitle = "One"

    let vc2 = self.storyboard?.instantiateViewController(withIdentifier: "page1")as! TestPageVC
    vc2.WordTitle = "Two"

    let vc3 = self.storyboard?.instantiateViewController(withIdentifier: "page1")as! TestPageVC
    vc3.WordTitle = "Three"

根据我执行此操作的日期来展示 VC：

    if Today == "23.10.2021" {
        arraypage1.append(vc1)

        if let firstVC = arraypage1.first {
            setViewControllers([firstVC], direction: .forward, animated: true, completion: nil)
        }
        
    } else if Today == "24.10.2021" {
        arraypage1.append(vc1)
        arraypage1.append(vc2)

        let otherVC = arraypage1[1]
         self.setViewControllers([otherVC], direction: .forward, animated: false, completion: nil)
        
    }  else if Today == "25.10.2021" {
        
        arraypage1.append(vc1)
        arraypage1.append(vc2)
        arraypage1.append(vc3)
        
        let otherVC = arraypage1[2]
         self.setViewControllers([otherVC], direction: .forward, animated: false, completion: nil)
    }

但是代码会太长，有很多数据

有一个更好的方法吗 ？

Answer 1

你需要学习如何使用UIPageViewControllerDelegate

https://developer.apple.com/documentation/uikit/uipageviewcontrollerdelegate/

它允许您以编程方式指定想要的视图，而不必每次都设置视图控制器数组。