我有一个RootViewController
创建一个SecondViewController
. 在SecondViewController
in 中viewDidAppear
,我创建了 aUIScrollView
和 aUIPageControl
并将它们添加到视图中。我也这样做:scrollview.delegate = self
。是SecondViewController
一个<UIScrollViewDelegate>
。我scrollViewDidScroll
也在SecondViewController
. 所有这些工作、编译和运行。但是,当我触摸 时UIScrollView
,应用程序崩溃了。对于我的生活,我无法弄清楚为什么。这是最愚蠢的问题,但我无法解决。
它与这个问题非常相似:UIScrollView EXC_BAD_ACCESS crash in iOS 但是,我尝试了这些解决方案,但都没有奏效。
我在下面粘贴了一些代码。我真的很感激帮助。
根视图控制器:
- (void)viewDidAppear:(BOOL)animated
{
SecondViewController *secondViewController = [[SecondViewController alloc] init];
secondViewController.view.frame = CGRectMake(50, 50, 925, 600);
secondViewController.view.backgroundColor = [UIColor lightGrayColor];
[self.view addSubview:secondViewController.view];
}
第二视图控制器:
- (void)viewDidAppear:(BOOL)animated
{
CGRect scrollViewFrame = CGRectMake(50, 50, 824, 500);
self.scrollView = [[UIScrollView alloc] initWithFrame:scrollViewFrame];
self.scrollView.delegate = self;
self.scrollView.contentSize = CGSizeMake(self.scrollView.frame.size.width*3,
self.scrollView.frame.size.height);
self.scrollView.backgroundColor = [UIColor darkGrayColor];
self.scrollView.showsHorizontalScrollIndicator = YES;
self.scrollView.showsVerticalScrollIndicator = YES;
self.scrollView.pagingEnabled = YES;
[self.view addSubview:self.scrollView];
CGRect pageControlFrame = CGRectMake(0, 0, 50, 20);
self.pageControl = [[UIPageControl alloc] initWithFrame:pageControlFrame];
self.pageControl.numberOfPages = 3;
self.pageControl.currentPage = 0;
self.pageControl.backgroundColor = [UIColor grayColor];
[self.view addSubview:self.pageControl];
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGFloat pageWidth = self.scrollView.frame.size.width;
float fractionalPage = self.scrollView.contentOffset.x / pageWidth;
NSInteger page = lround(fractionalPage);
self.pageControl.currentPage = page;
}