UICollectionView实现无限图片轮播

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目的：无限图片轮播

技术：UICollectionView

技术要点：利用UICollectionViewCell的重用实现无限图片轮播，实例提供5张图片

主控制器代码

//  ViewController.m

//  UICollectionView-无限轮播-demo

#import "ViewController.h"

#import "BQAdvCell.h"

#import "BQBeauty.h"

@interface ViewController ()<UICollectionViewDataSource,UICollectionViewDelegate,UIScrollViewDelegate>

@property (weak, nonatomic) IBOutlet UICollectionView *collectionView;

@property (strong, nonatomic) NSArray *beauties;

@property (weak, nonatomic) IBOutlet UIPageControl *pageControl;

@property (strong,nonatomic) NSTimer *timer;

@end

@implementation ViewController

-(NSArray *)beauties{

    if (_beauties == nil) {

        NSString *path = [[NSBundle mainBundle]pathForResource:@"beauties" ofType:@"plist"];

        NSArray *dictArray = [NSArray arrayWithContentsOfFile:path];

        NSMutableArray *array = [NSMutableArray array];

        for (NSDictionary *dict in dictArray) {

            BQBeauty *beauty = [BQBeauty beautyWithDict:dict];

            [array addObject:beauty];

        }

        _beauties = array;

    }

    return _beauties;

}

- (void)viewDidLoad {

    [super viewDidLoad];

    //设置代理

    self.collectionView.dataSource = self;

    self.collectionView.delegate = self;

    //注册cell

    [self.collectionView registerNib:[UINib nibWithNibName:@"BQAdvCell" bundle:nil]forCellWithReuseIdentifier:@"beauty"];

    //默认选择5000组

    [self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:50 inSection:0]atScrollPosition:UICollectionViewScrollPositionLeft animated:NO];

    //设置pageControl

    //1.总页数

    self.pageControl.numberOfPages = self.beauties.count;

    //定时器

    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:5.0 target:self selector:@selector(bro) userInfo:nil repeats:YES];

    self.timer = timer;

    [[NSRunLoop mainRunLoop] addTimer:timer forMode:NSDefaultRunLoopMode];

}

-(void)bro{

    static int index = 0;

    if (index == 5) {

        index = 0;

    }

    [self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:50+index inSection:0]atScrollPosition:UICollectionViewScrollPositionLeft animated:NO];

    index++;

}

#pragma mark - UICollectionViewDataSource

//返回多少组

-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{

    return 1;

}

//返回多少个

-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{

    return self.beauties.count * 100;

}

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{

    //1.去缓存池取cell

    BQAdvCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"beauty" forIndexPath:indexPath];

    //2.设置cell

    cell.beauty = self.beauties[indexPath.item % 5];

    //3.返回cell

    return cell;

}

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

    int page = scrollView.contentOffset.x / 300;

    self.pageControl.currentPage = page % 5;

}

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

    //关闭定时器

    [self.timer setFireDate:[NSDate distantFuture]];

}

-(void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset{

    //开启定时器

    [self.timer setFireDate:[NSDate distantPast]];

}

UICollectionView实现无限图片轮播

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原文地址：http://www.cnblogs.com/newFansOne/p/4824384.html