UIPageControl 指示点在页面更改时不会更改

Posted 2023-03-14

【中文标题】UIPageControl 指示点在页面更改时不会更改

【英文标题】：UIPageControl indicator dot does not change when the page changes

【发布时间】：2014-03-06 21:17:01

【问题描述】：

我遇到了UIPagecotrol 的问题。它没有在模拟器中激活。点不会更改到下一个视图。

- (void)viewWillAppear:(BOOL)animated 
    [super viewWillAppear:animated];

    for (NSUInteger i =0; i < [self.childViewControllers count]; i++) 
        [self loadScrollViewWithPage:i];
    

    self.pageControl.currentPage = 0;
    _page = 0;
    [self.pageControl setNumberOfPages:[self.childViewControllers count]];

    UIViewController *viewController = [self.childViewControllers objectAtIndex:self.pageControl.currentPage];
    if (viewController.view.superview != nil) 
        [viewController viewWillAppear:animated];

    

    self.scrollView.contentSize = CGSizeMake(scrollView.frame.size.width * [self.childViewControllers count], scrollView.frame.size.height);


- (void)loadScrollViewWithPage:(int)page 
    if (page < -0)
        return;
    if (page >= [self.childViewControllers count])
        return;

    // replace the placeholder if necessary
    UIViewController *controller = [self.childViewControllers objectAtIndex:page];
    if (controller == nil) 
        return;
    

    // add the controller's view to the scroll view
    if (controller.view.superview == nil) 
        CGRect frame = self.scrollView.frame;
        frame.origin.x = frame.size.width * page;
        frame.origin.y = 0;
        controller.view.frame = frame;
        [self.scrollView addSubview:controller.view];
    



// At the begin of scroll dragging, reset the boolean used when scrolls originate from the UIPageControl
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView 
    _pageControlUsed = NO;


// At the end of scroll animation, reset the boolean used when scrolls originate from the UIPageControl
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView 
    _pageControlUsed = NO;


- (IBAction)changePage:(id)sender; 

这里的源代码：https://mega.co.nz/#F!0EkBQbTK!bKjEwFf7BQsUx0YGtoHehw

只需以 zip 格式下载并在 Xcode 中运行。请注意，UIPageControl 不会随当前页面移动。

【参考方案1】：

你可以看看这篇博客文章：http://mobileappdev.learningtree.com/2012/12/18/paging-with-collection-views-part-2/ ...我只是用它来设置我的 UIPageControl 元素，它工作正常。您可能需要根据您的特定需求对其进行一些调整...