UIScrollview + UIPageControl 实现简单例子

#define   NewfeatureCount  4

@interface NewfeatureViewController ()<UIScrollViewDelegate>

@property(nonatomic,weak)  UIPageControl  *pageControl;

@end

- (void)viewDidLoad {

    [super viewDidLoad];

    //创建一个scrollview:显示所有的新特性

    UIScrollView  *scrollView = [[UIScrollView  alloc]init];

    scrollView.frame = self.view.bounds;

    [self.view  addSubview:scrollView];

    for (int  i = 0; i < NewfeatureCount; i++) {

        UIImageView  *image = [[UIImageView  alloc]init];

        image.size = scrollView.size;

        image.y = 0 ;

        image.x = i * image.width;

        //显示图片

        NSString  *name = [NSString  stringWithFormat:@"new_feature_%d",i+1];

        image.image = [UIImage  imageNamed:name];

        [scrollView  addSubview:image];

    }

    

    //如果想要某个方向不能滚动，那就就该方向上的值设置为0

    scrollView.contentSize = CGSizeMake(NewfeatureCount * scrollView.width, 0);

    

    scrollView.bounces = NO;//去除弹簧效果

    scrollView.pagingEnabled = YES;

    scrollView.showsHorizontalScrollIndicator = NO;

    scrollView.delegate = self;

    

    //添加pageControl：设置分页

    

    UIPageControl  *pageControl = [[UIPageControl  alloc]init];

    pageControl.numberOfPages = NewfeatureCount;

    pageControl.width = 100;

    pageControl.height = 50;

    //pageControl.backgroundColor = [UIColor  redColor];

    pageControl.centerX = scrollView.width * 0.5;

    pageControl.centerY = scrollView.height -50;

    pageControl.currentPageIndicatorTintColor = [UIColor  redColor];   

    pageControl.pageIndicatorTintColor = [UIColor  grayColor];

    pageControl.userInteractionEnabled = NO;//不许与用户界面交互

    [self.view  addSubview:pageControl];

    self.pageControl = pageControl;

    

}

-(void)scrollViewDidScroll:(UIScrollView *)scrollView{

    double  page = scrollView.contentOffset.x / scrollView.width;

    

    //四舍五入计算页面

    self.pageControl.currentPage = (int)(page + 0.5);

}