可以循环滚动的展示图

ViewController.h

@interface ViewController : UIViewController<UIScrollViewDelegate>
{
NSInteger _index;
UIPageControl *_pageCtrl;
UIScrollView *_scrollerView;
}
ViewController.m
#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
[super viewDidLoad];

_scrollerView= [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
_scrollerView.delegate = self;
_scrollerView.backgroundColor = [UIColor redColor];
_scrollerView.pagingEnabled = YES;
_scrollerView.showsHorizontalScrollIndicator = NO;
_scrollerView.contentSize = CGSizeMake(320*6, 480);
[self.view addSubview:_scrollerView];

for (int i=0; i<6; i++) {
NSString *name = [NSString stringWithFormat:@"%d",i];
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:name]];
imageView.frame = CGRectMake(320*i, 0, 320, 480);
[_scrollerView addSubview:imageView];
}

_pageCtrl = [[UIPageControl alloc] initWithFrame:CGRectMake(20, 400, 280, 30)];
_pageCtrl.backgroundColor = [UIColor grayColor];
_pageCtrl.numberOfPages = 5;
[self.view addSubview:_pageCtrl];

//自动滑动
[NSTimer scheduledTimerWithTimeInterval:2
target:self
selector:@selector(timeAction:)
userInfo:nil
repeats:YES];

}

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

int count = scrollView.contentOffset.x/320;
//实现循环滑动
if (count == 5) {
//重点是这句话
scrollView.contentOffset = CGPointMake(0, 0);
_pageCtrl.currentPage = 0;

}else {
_pageCtrl.currentPage = count;
}
}

- (void)timeAction:(NSTimer *)time {

_index ++;
if (_index == 5) {
_index = 0;
}
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:.5];
_scrollerView.contentOffset = CGPointMake(_index*320, 0);
[UIView commitAnimations];

_pageCtrl.currentPage = _scrollerView.contentOffset.x/320;
}

@end