iOS UIScrollView自动轮播图片效果（只需一行代码就可集成到自己的项目中）

1. 简介

效果使用到的ＵＩ： UIScrollView  + UIPageControl + UIImageView + UILabel

本示例将UIScrollView自动轮播效果封装成一个自定义的控件，集成时只需一行代码就可以集成到自己的效果，初始化时只需给出数据源即可

2.使用步骤：

1. 将 LoopScrollImageView.h、LoopScrollImageView.h 拖到 自己的项目中

        2. 在使用的时候调用初始化方法： - (id) initWithFrame:(CGRect)frame images:(NSArray *)images 即可完成轮播效果

3. 示例：

- (void)viewDidLoad {    [super viewDidLoad];    self.title = @"UIImage自动轮播";        NSArray *  imageDataSource = [NSArray arrayWithObjects:@"1.jpg", @"2.jpg", @"3.jpg", nil];    // 只需初始化就可以实现效果    LoopScrollImageView * loopScrollImageView =[[LoopScrollImageView alloc] initWithFrame:CGRectMake(0, 64, self.view.frame.size.width, 130) images:imageDataSource];    [self.view addSubview:loopScrollImageView];}

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#import <UIKit/UIKit.h>@interface LoopScrollImageView : UIView <UIScrollViewDelegate> {    }@property (nonatomic, retain) NSTimer * timer;@property (nonatomic, retain) UIScrollView * scrollView;@property (nonatomic, retain) UIPageControl * pageControl;@property (nonatomic, retain) UILabel * currentPageLabel;@property (nonatomic, retain) NSArray * dataSource;- (id) initWithFrame:(CGRect)frame images:(NSArray *)images;- (void) startTimer;- (void) stopTimer;@end

#import "LoopScrollImageView.h"@implementation LoopScrollImageView - (id) initWithFrame:(CGRect)frame images:(NSArray *)images {    if (self = [super initWithFrame:frame]) {        self.dataSource = images;        // 1. 初始化定时器        _timer = [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(loopImageTimer:) userInfo:nil repeats:YES];        //[timer setFireDate:[NSDate distantFuture]];                CGFloat viewWidth = CGRectGetWidth(self.frame);        CGFloat viewHeigh = CGRectGetHeight(self.frame);        NSUInteger pageCount = images.count;                // 2. 初始化UIScrollView        _scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, viewWidth, viewHeigh)];        _scrollView.contentSize = CGSizeMake(viewWidth * pageCount, viewHeigh);        _scrollView.showsVerticalScrollIndicator = NO;        _scrollView.showsHorizontalScrollIndicator = NO;        _scrollView.pagingEnabled = YES;        _scrollView.delegate = self;                for (int i = 0; i < images.count; i++) {            UIImageView * imageView = [[UIImageView alloc] initWithFrame:CGRectMake(viewWidth * i, 0, viewWidth, viewHeigh)];            imageView.contentMode = UIViewContentModeScaleAspectFill;            imageView.image = [UIImage imageNamed:images[i]];            imageView.tag = i;            imageView.userInteractionEnabled = YES;            UITapGestureRecognizer * tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(loopImageOnClicked:)];            [imageView addGestureRecognizer:tap];                        [_scrollView addSubview:imageView];        }                [self addSubview:_scrollView];                if (images.count > 1) {            // 3. 初始化UIPageControl            int pageControllHeight = 30;            CGFloat scrollViewBottom = _scrollView.frame.origin.y + _scrollView.frame.size.height;            _pageControl = [[UIPageControl alloc] initWithFrame:CGRectMake(10, scrollViewBottom - pageControllHeight, 100, pageControllHeight)];            _pageControl.currentPage = 0;            _pageControl.numberOfPages = pageCount;            _pageControl.backgroundColor = [UIColor grayColor];            [self addSubview:_pageControl];                        // 4. 初始化 当前页/总页数            _currentPageLabel = [[UILabel alloc] initWithFrame:CGRectMake(viewWidth - 50, _pageControl.frame.origin.y, 50, pageControllHeight)];            _currentPageLabel.text = [NSString stringWithFormat:@"%d/%ld", 1, images.count];            [self addSubview:_currentPageLabel];        }    }        return self;}- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {    if ([scrollView isMemberOfClass:[UITableView class]]) {            }else {        int index = fabs(scrollView.contentOffset.x) / scrollView.frame.size.width;   //当前是第几个视图        _pageControl.currentPage = index;                _currentPageLabel.text = [NSString stringWithFormat:@"%d/%ld", index + 1, self.dataSource.count];    }}#pragma mark -#pragma mark - Actions- (void) loopImageTimer:(NSTimer *)timer {    NSUInteger totalNum = self.dataSource.count;    if (totalNum > 1) {        CGPoint newOffset = _scrollView.contentOffset;        newOffset.x = newOffset.x + CGRectGetWidth(_scrollView.frame);        if (newOffset.x > (CGRectGetWidth(_scrollView.frame) * (totalNum-1))) {            newOffset.x = 0 ;        }        int index = newOffset.x / CGRectGetWidth(_scrollView.frame);   //当前是第几个视图        newOffset.x = index * CGRectGetWidth(_scrollView.frame);                _pageControl.currentPage = index;        _currentPageLabel.text = [NSString stringWithFormat:@"%d / %ld",index+1, totalNum];        [_scrollView setContentOffset:newOffset animated:YES];    }else{        [_timer setFireDate:[NSDate distantFuture]];//关闭定时器    }}- (void) loopImageOnClicked:(UITapGestureRecognizer *) tapGestureRecognizer{    NSInteger imageViewTag = tapGestureRecognizer.view.tag;    NSLog(@"imageViewTag: ----------------- %ld", imageViewTag);        // 0, 1, 2}#pragma mark -#pragma mark - Methods- (void) startTimer {    [_timer setFireDate:[NSDate distantPast]];}- (void) stopTimer {    [_timer setFireDate:[NSDate distantFuture]];}@end

实现效果如图：