UIPageControl是分页符，在新闻类的APP中很常见，随着新闻页面的滚动，在屏幕中会有一些小点，也随着移动，用来分辨当前的页数，就是UIPageControl和ScrollView的结合使用；
直接给大家上代码，这样更有助于理解：
1 page = [[UIPageControl alloc] initWithFrame:CGRectMake(20, 30, 200, 40)]; 2 page.backgroundColor = [UIColor clearColor]; 3 page.numberOfPages = 3;//设置页数（多少个点） 4 page.currentPage = 0;//设置当前选中页 5 NSLog(@"%d",page.currentPage);//获取当前选中页下标 6 page.pageIndicatorTintColor = [UIColor greenColor];//未选中颜色 7 page.currentPageIndicatorTintColor = [UIColor redColor];//当前选中的颜色 8 [page addTarget:self action:@selector(change:) forControlEvents:UIControlEventValueChanged]; 9 [self.view addSubview:page]; 10 11 UIPageControl与UIScrollView 的结合使用 12 13 #import "ViewController.h" 14 15 @interface ViewController ()<UIScrollViewDelegate>{ 16 UIPageControl *page; 17 UIScrollView *scrollView; 18 } 19 20 @end 21 22 @implementation ViewController 23 24 - (void)viewDidLoad { 25 [super viewDidLoad]; 26 27 page = [[UIPageControl alloc] initWithFrame:CGRectMake(20, 30, 200, 40)]; 28 page.backgroundColor = [UIColor clearColor]; 29 page.numberOfPages = 3;//设置页数（多少个点） 30 page.currentPage = 0;//设置当前选中页 31 NSLog(@"%d",page.currentPage);//获取当前选中页下标 32 page.pageIndicatorTintColor = [UIColor greenColor];//未选中颜色 33 page.currentPageIndicatorTintColor = [UIColor redColor];//当前选中的颜色 34 [page addTarget:self action:@selector(change:) forControlEvents:UIControlEventValueChanged]; 35 [self.view addSubview:page]; 36 37 scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(20, 90, 300, 400)]; 38 scrollView.contentSize = CGSizeMake(900, 0); 39 scrollView.delegate = self; 40 scrollView.pagingEnabled = YES; 41 [self.view addSubview:scrollView]; 42 43 UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 300, 400)]; 44 view.backgroundColor = [UIColor grayColor]; 45 [scrollView addSubview:view]; 46 47 UIView *view1 = [[UIView alloc] initWithFrame:CGRectMake(300, 0, 300, 400)]; 48 view1.backgroundColor = [UIColor brownColor]; 49 [scrollView addSubview:view1]; 50 51 UIView *view2 = [[UIView alloc] initWithFrame:CGRectMake(600, 0, 300, 400)]; 52 view2.backgroundColor = [UIColor purpleColor]; 53 [scrollView addSubview:view2]; 54 55 56 } 57 58 -(void)change:(id)page{ 59 NSLog(@"--%zi",[page currentPage]); 60 61CGPoint p = {[page currentPage]*300,0};//获取分页符当前的页数与view的宽相乘作为CGPoint的x
62 [scrollView setContentOffset:p animated:YES];//将p赋给scrollView的当前滚动位置，就建立了联系
63 }
64
65
-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
66 int index = scrollView.contentOffset.x/scrollView.frame.size.width;//当scrollView滚动停止时，将scrollView当前滚动到的位置除以view的宽，获得的值就是页数
67 page.currentPage = index; //将上面获得的页数赋给page，就是page的当前页
68 }
69
70 - (void)didReceiveMemoryWarning {
71 [super didReceiveMemoryWarning];
72 // Dispose of any resources that can be recreated.
73 }
74
75 @end