XX问我一个问题，就是以前做过的无线滚动，，-_-||，突然发现没什么印象了，于是赶紧做了个Demo熟悉一下，其实也挺简单的
原理：改变数组，重新加载图片，偏移量1，2，3达到3瞬间回到2，达到2，瞬间回到1
利用3个UIImageView多次利用
贴代码：
//// ViewController.m// 测试-滚动//// Created by lanqs on 15/2/7.// Copyright (c) 2015年 Tanqihong. All rights reserved.//#import "ViewController.h"@interface ViewController ()<UIScrollViewDelegate>@property (nonatomic,strong)UIScrollView *scrollView;@property (nonatomic,strong)NSMutableArray *array;@property (nonatomic,strong)NSMutableArray *imageArray;@property (nonatomic,strong)NSTimer *timer;@end@implementation ViewController#pragma mark – 懒加载- (NSMutableArray *)array {if (!_array) {_array = [[NSMutableArray alloc]initWithObjects:@"QQ20150207-2.png",@"QQ20150207-3.png",@"QQ20150207-4.png",@"QQ20150207-5.png",@"QQ20150207-6.png", nil];}return _array;}- (NSMutableArray *)imageArray {if (!_imageArray) {_imageArray = [[NSMutableArray alloc]init];}return _imageArray;}#pragma mark – viewDidLoad- (void)viewDidLoad {[super viewDidLoad];_scrollView = [[UIScrollView alloc]initWithFrame:self.view.bounds];_scrollView.backgroundColor = [UIColor grayColor];_scrollView.contentSize = CGSizeMake(CGRectGetWidth(self.view.bounds)*3, CGRectGetHeight(self.view.bounds));_scrollView.pagingEnabled = YES;_scrollView.delegate = self;[self.view addSubview:_scrollView];for (int i = 0; i < 3; i ++) {UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(i * CGRectGetWidth(self.view.bounds), 0, CGRectGetWidth(self.view.bounds), CGRectGetHeight(self.view.bounds))];[imageView setImage:[UIImage imageNamed:self.array[i]]];imageView.layer.borderWidth = 1;[_scrollView addSubview:imageView];//在imageArray上添加3个imageView[self.imageArray addObject:imageView];}//设置这个是为了自动轮播做准备_scrollView.contentOffset = CGPointMake(CGRectGetWidth(self.view.bounds), 0);_timer = [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(processTimer) userInfo:nil repeats:YES];}#pragma mark – Timer- (void)processTimer {//有滑动效果的//当他到CGRectGetWidth(self.view.bounds) *2 这个偏移量的时候就会触发滚动视图的滚动方法//效果是，回到中间，然后再偏移，再回到，循环滚动就完成了[_scrollView setContentOffset:CGPointMake(CGRectGetWidth(self.view.bounds) *2, 0) animated:YES];}#pragma mark – 重新加载数组里面的图片- (void)setImageToImageView {NSInteger i = 0;//因为只有3个所以循环3呲牙for (UIImageView *imageView in self.imageArray) {//给imageArray 添加改变后的图片（向左或者向右移动一张图片的）//遍历，你改变遍历里面的元素，self.imageArray会改变的[imageView setImage:[UIImage imageNamed:self.array[i]]];i ++;}}#pragma mark – <UIScrollViewDelegate>- (void)scrollViewDidScroll:(UIScrollView *)scrollView {if (scrollView.contentOffset.x >= 2 * CGRectGetWidth(self.view.bounds)) {//向右滚动//a,b,c三个位置//当滑动的超过这个距离的时候其实已经瞬间回到b的位置了//就相当于你拉着b在向c滑动//复制数组中第一张图id fisrtImageName = [self.array[0] mutableCopy];//删除数组中第一张图[self.array removeObjectAtIndex:0];//添加这张图，到数组的末尾[self.array addObject:fisrtImageName];}else if (scrollView.contentOffset.x <= 0) {//向左滚动//同上…id lastImageName = [self.array.lastObject mutableCopy];[self.array removeLastObject];[self.array insertObject:lastImageName atIndex:0];}else {return;}[self setImageToImageView];scrollView.contentOffset = CGPointMake(CGRectGetWidth(self.view.bounds), 0);}@end效果图：
一遍一遍的……你突然明白自己还活着，
