将页面控件设置到 UIPageViewController 的顶部

Posted 2023-03-14

【中文标题】将页面控件设置到 UIPageViewController 的顶部

【英文标题】：Set page control to the top of UIPageViewController

【发布时间】：2018-04-07 16:51:43

【问题描述】：

目前我想使用 UIPageViewController。但默认情况下，页面控件会自动放置在屏幕底部。那么我怎样才能实现如下图所示页面控件位于顶部的位置

我使用容器视图并将视图控制器更改为 uipageviewcontroller

更新

class ProfilePageViewController: UIPageViewController, UIPageViewControllerDelegate, UIPageViewControllerDataSource 

var pageControl = UIPageControl(frame: CGRect(x: 0,y: 0,width: UIScreen.main.bounds.width,height: 50))
lazy var VCArr: [UIViewController] = 
    return [self.VCInstance(name: "button1"),
            self.VCInstance(name: "button2"),
            self.VCInstance(name: "button3")]
()

override func viewDidLayoutSubviews() 
    super.viewDidLayoutSubviews()
    for view in self.view.subviews 
        if view is UIScrollView 
            view.frame = UIScreen.main.bounds
         else if view is UIPageControl 
            view.backgroundColor = UIColor.clear
        
    


private func VCInstance(name: String) -> UIViewController 
    return UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: name)


override func viewDidLoad() 
    super.viewDidLoad()
    self.dataSource = self
    self.delegate = self
    pageControl.currentPageIndicatorTintColor = UIColor.green
    pageControl.pageIndicatorTintColor = UIColor.gray
    if let firstVC = VCArr.first 
        setViewControllers([firstVC], direction: .forward, animated: true, completion: nil)
    




public func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? 
    guard let viewControllerIndex = VCArr.index(of: viewController) else 
        return nil
    

    let previousIndex = viewControllerIndex - 1

    guard previousIndex >= 0 else 
        return VCArr.last
        //uncomment atas comment bawa untuk loop
        //return nil
    

    guard VCArr.count > previousIndex else 
        return nil
    

    return VCArr[previousIndex]



public func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController? 
    guard let viewControllerIndex = VCArr.index(of: viewController) else 
        return nil
    

    let nextIndex = viewControllerIndex + 1

    guard nextIndex < VCArr.count else 
        return VCArr.first
        //uncomment atas, comment bawah untuk loop
        //return nil
    

    guard VCArr.count > nextIndex else 
        return nil
    

    return VCArr[nextIndex]



public func presentationCount(for pageViewController: UIPageViewController) -> Int 
    return VCArr.count



public func presentationIndex(for pageViewController: UIPageViewController) -> Int 
    guard let firstViewController = viewControllers?.first,
        let firstViewControllerIndex = VCArr.index(of: firstViewController) else 
            return 0
    

    return firstViewControllerIndex

我已经更新了我已经做的最新代码，但页面控件似乎仍在页面底部。

下面是我当前页面控件的图片

【参考方案1】：

不要从外观上使用默认的 UIPageControl。删除那些块。 根据您的视图矩形和位置创建一个新的 UIPageControl。

在 UIpagecontrol 的框架中：设置 y = 0 表示顶部或 UIScreen.main.bounds.maxY - 偏移量

这里是示例代码

 //1 : member variable
 var pageControl = UIPageControl()

// Call it from viewDidLoad
func setupPageControl() 
   // 2: set y = 0 means top or UIScreen.main.bounds.maxY - offset
    pageControl = UIPageControl(frame: CGRect(x: 0,y: 0,width: UIScreen.main.bounds.width,height: 50))
    self.pageControl.numberOfPages = pageCount
   // self.pageControl.currentPage = 0
    self.pageControl.tintColor = UIColor.lightGray
    self.pageControl.pageIndicatorTintColor = UIColor.lightGray
    self.pageControl.currentPageIndicatorTintColor = UIColor.black
    pageControl.backgroundColor = UIColor.clear
    self.view.addSubview(pageControl)

您需要从 viewControllerAfter () & viewControllerBefore

更新当前页面 (pageControl.currentPage = count)

【讨论】：

我已经在页面控件上添加了 cgrect，但它仍然出现在页面底部

在viewdidLoad中，添加self.view.addSubview(pageControl)

添加到子视图后告诉我结果。