iOS:UIScrollView控件和UIPageControl控件的详解

 1 #import "ViewController.h"
 2 
 3 @interface ViewController ()<UIScrollViewDelegate> //实现滚动视图协议
 4 @property (strong,nonatomic)UIScrollView *scrollview; //滚动视图控件对象
 5 @property (strong,nonatomic)UIPageControl *pagecontrol;//分页控制控件对象
 6 @end
 7 
 8 @implementation ViewController
 9 
10 - (void)viewDidLoad {
11     [super viewDidLoad];
12     //创建ScrollView并初始化
13     self.scrollview = [[UIScrollView alloc]initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
14     //将滚动视图添加到视图控制器控制的视图View容器中
15     [self.view addSubview:self.scrollview];
16     
17     
18     //创建5个imageView对象并加载图片
19     CGFloat x = 0;
20     CGFloat y = 0;
21     UIImage *image;
22     for(int i=0; i<5; i++)
23     {
24         UIImageView *imageview = [[UIImageView alloc]init];
25         image = [UIImage imageNamed:[NSString stringWithFormat:@"s%d.jpg",i+1]];
26         [imageview setImage:image];
27         //设置每一个图像视图imageView的frame矩形区域
28         imageview.frame = CGRectMake(x+self.view.frame.size.width*i, y, self.view.frame.size.width, image.size.height);
29         //设置图像模式，使图片变动时，图片不失真
30         imageview.contentMode = UIViewContentModeScaleAspectFit;
31         //将图像视图添加到滚动视图容器中
32         [self.scrollview addSubview:imageview];
33     }
34     
35     //设置scrollView
36     self.scrollview.contentSize = CGSizeMake(5*self.view.frame.size.width, self.view.frame.size.height);//有多少图片,那么滚动视图的滚动宽度就等于图片数量乘以你所设置的单个滚动视图矩形区域的宽度
37     self.scrollview.contentOffset = CGPointZero;//默认滚动视图的初始原点位置都为0
38     self.scrollview.pagingEnabled = YES;//设置滚动视图可以进行分页
39     self.scrollview.delegate = self;//设置滚动视图的代理
40     
41     //创建初始化并设置PageControl
42     self.pagecontrol = [[UIPageControl alloc]init];
43     self.pagecontrol.bounds = CGRectMake(0, 0, 100, 50);
44     self.pagecontrol.center = self.view.center;
45     self.pagecontrol.numberOfPages = 5; //因为有5张图片，所以设置分页数为5
46     self.pagecontrol.currentPage  = 0; //默认第一页页数为0
47     //设置分页控制点颜色
48     self.pagecontrol.pageIndicatorTintColor = [UIColor redColor];//未选中的颜色
49     self.pagecontrol.currentPageIndicatorTintColor = [UIColor greenColor];//选中时的颜色
50     //添加分页控制事件用来分页
51     [self.pagecontrol addTarget:self action:@selector(pageControlChanged:) forControlEvents:UIControlEventValueChanged];
52     //将分页控制视图添加到视图控制器视图中
53     [self.view addSubview:self.pagecontrol];
54     //设置试图控制器背景色为黑色
55     self.view.backgroundColor = [UIColor blackColor];
56 }
57 #pragma mark - pageControll的事件响应
58 -(void)pageControlChanged:(UIPageControl*)sender
59 {
60     /*
61     //NSLog(@"%ld",sender.currentPage);
62     CGRect frame;
63     frame.origin.x = self.scrollview.fram
64      e.size.width * sender.currentPage;
65     frame.origin.y = 0;
66     frame.size = self.scrollview.frame.size;
67     [self.scrollview scrollRectToVisible:frame animated:YES];
68     */
69     或者
70     //计算scrollview相应地contentOffset
71     CGFloat x = sender.currentPage * self.scrollview.frame.size.width;
72     self.scrollview.contentOffset = CGPointMake(x,0);
73     
74 }
75 
76 #pragma mark - scrollView的代理方法
77 -(void)scrollViewDidScroll:(UIScrollView *)scrollView
78 {
79     //计算pagecontroll相应地页(滚动视图可以滚动的总宽度/单个滚动视图的宽度=滚动视图的页数)
80     NSInteger currentPage = (int)(scrollView.contentOffset.x) / (int)(self.view.frame.size.width);
81     self.pagecontrol.currentPage = currentPage;//将上述的滚动视图页数重新赋给当前视图页数,进行分页
82 }
83 @end