UIPageControl

• 简单使用

1.    pageControl = [[UIPageControl alloc] init];
2.    pageControl.frame = CGRectMake((self.view.bounds.size.width - 100) / 2.0,
3.                                   self.view.frame.size.height - 40,
4.                                   100,
5.                                   20);
6.    pageControl.numberOfPages = 3; // 一共有多少项（也就是有多少个圆点）
7.    pageControl.pageIndicatorTintColor = [UIColor darkGrayColor]; // 指示器的颜色
8.    pageControl.currentPageIndicatorTintColor = [UIColor cyanColor]; //指示器的当前颜色
9.
10.    [self.view addSubview:pageControl];
11.

• pageControl结合scrollView使用,scrollView必须打开分页，示例如下

1.#import "ViewController.h"
2.
3.@interface ViewController ()<UIScrollViewDelegate>
4.{
5.    UIScrollView *scrollView;
6.    UIPageControl *pageControl;
7.}
8.@end
9.
10.@implementation ViewController
11.
12.- (void)viewDidLoad {
13.    [super viewDidLoad];
14.
15.
16.    scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
17.    scrollView.bounces = NO;
18.    scrollView.showsHorizontalScrollIndicator = NO;
19.    scrollView.showsVerticalScrollIndicator = NO;
20.
21.    CGFloat foreX = self.view.frame.size.width;
22.    for (int i = 1; i <= 3; i++) {
23.        NSString *str = [NSString stringWithFormat:@"%d.jpg",i];
24.        UIImage *image = [UIImage imageNamed:str];
25.        CGSize size = image.size;
26.        UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
27.        imageView.frame = CGRectMake(foreX * (i - 1), 20, size.width, self.view.frame.size.height - 20);
28.
29.        [scrollView addSubview:imageView];
30.    }
31.
32.    scrollView.contentSize = CGSizeMake(3 * foreX, self.view.frame.size.height - 20);
33.
34.    [self.view addSubview:scrollView];
35.
36.    scrollView.pagingEnabled = YES;// 启用翻页模式(不能会停在两个页面中间)
37.
38.    scrollView.delegate = self;
39.
40.    pageControl = [[UIPageControl alloc] init];
41.    pageControl.frame = CGRectMake((self.view.bounds.size.width - 100) / 2.0,
42.                                   self.view.frame.size.height - 40,
43.                                   100,
44.                                   20);
45.    pageControl.numberOfPages = 3; // 一共有多少项（也就是有多少个圆点）
46.    pageControl.pageIndicatorTintColor = [UIColor darkGrayColor]; // 指示器的颜色
47.    pageControl.currentPageIndicatorTintColor = [UIColor cyanColor]; //指示器的当前颜色
48.
49.    [self.view addSubview:pageControl];
50.
51.}
52.// 在scroll滚动到下一页后，改变pageControl的当前页
53.-(void)scrollViewDidScroll:(UIScrollView *)_scrollView{
54.
55.    CGPoint offset = _scrollView.contentOffset;
56.    CGFloat w = self.view.frame.size.width;
57.
58.    pageControl.currentPage = (NSInteger)(offset.x / w);
59.
60.}
61.
62.
63.@end