轮播器(一)--UIScrollView实现图片轮播

此篇文章主要介绍如何采用UIScrollView来实现轮播图，加入定时器来实现自动轮播

#import <UIKit/UIKit.h>@protocol CarouselDelegate <NSObject>//图片的点击事件-(void)clickedAtIndex:(NSInteger)index;@end@interface CarouselView1 : UIView//代理@property (nonatomic,assign) id<CarouselDelegate> delegate;//初始化-(instancetype)initWithFrameAndData:(CGRect)frame data:(NSMutableArray *)dataModel;//开启自动滚动-(void)startAutoScroll;//停止自动滚动-(void)stopAutoScroll;@end

#import "CarouselView1.h"#import "UIImageView+WebCache.h"#import "CarouselModel.h"@interface CarouselView1 ()<UIScrollViewDelegate>//装载轮播图的scrollView@property (weak, nonatomic) IBOutlet UIScrollView *scrollView;//页码@property (weak, nonatomic) IBOutlet UIPageControl *pageControl;//数据源@property (strong,nonatomic) NSMutableArray *dataArr;//滚动的计时器@property (strong,nonatomic) NSTimer *timer;//是否开启自动滚动,默认不开启@property (assign,nonatomic) BOOL autoScroll;@end@implementation CarouselView1-(instancetype)initWithFrameAndData:(CGRect)frame data:(NSMutableArray *)dataModel{    if (self = [super initWithFrame:frame]) {        self = [[NSBundle mainBundle] loadNibNamed:@"CarouselView1" owner:nil options:nil][0];        self.frame = frame;        self.dataArr = dataModel;        [self initCarouselView];    }    return self;}-(void)initCarouselView{    CGFloat imageW = self.frame.size.width;    CGFloat imageH = self.frame.size.height;    CGFloat imageY = 0;    CGFloat imageX = 0;        //初始化    self.scrollView.delegate = self;    self.scrollView.backgroundColor = [UIColor lightGrayColor];        //添加图片    for (int i = 0; i < self.dataArr.count; i++) {        imageX = i * imageW;        UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(imageX, imageY, imageW, imageH)];        imageView.tag = 1000 + i;        imageView.userInteractionEnabled = YES;        CarouselModel *model = [self.dataArr objectAtIndex:i];        [imageView sd_setImageWithURL:[[NSURL alloc] initWithString:model.imageUrl] placeholderImage:[UIImage imageNamed:@"1"]];        [self.scrollView addSubview:imageView];                //添加imageView的点击事件        UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(imageViewTaped:)];        [imageView addGestureRecognizer:tap];    }        //设置内容区域    self.scrollView.contentSize = CGSizeMake(self.dataArr.count * imageW, 0);    self.scrollView.showsHorizontalScrollIndicator = NO;    self.scrollView.showsVerticalScrollIndicator = NO;    self.scrollView.pagingEnabled = YES;        //设置分页页数    self.pageControl.currentPage = 0;    self.pageControl.numberOfPages = self.dataArr.count;    self.pageControl.currentPageIndicatorTintColor = [UIColor whiteColor];    self.pageControl.pageIndicatorTintColor = [UIColor grayColor];    self.pageControl.userInteractionEnabled = NO;        if(self.autoScroll)    {        [self startTimer];    }}-(void)imageViewTaped:(UITapGestureRecognizer *)sender{    NSLog(@"+++++++++:%ld",sender.view.tag);    if ([self.delegate respondsToSelector:@selector(clickedAtIndex:)]) {        [self.delegate clickedAtIndex:sender.view.tag];    }}//开始自动滚动- (void)startTimer{    self.timer = [NSTimer timerWithTimeInterval:2.0 target:self selector:@selector(updateTimer) userInfo:nil repeats:YES];    [[NSRunLoop mainRunLoop] addTimer:self.timer forMode:NSDefaultRunLoopMode];}//开启自动滚动-(void)startAutoScroll{    self.autoScroll = YES;    [self startTimer];}//停止自动滚动-(void)stopAutoScroll{    self.autoScroll = NO;    [self.timer invalidate];    self.timer = nil;}- (void)updateTimer{    self.pageControl.currentPage = (self.pageControl.currentPage + 1) % self.dataArr.count;    [self pageChanged:self.pageControl];}#pragma mark - 分页控件监听方法- (void)pageChanged:(UIPageControl *)page{    CGFloat x = page.currentPage * self.scrollView.bounds.size.width;    [self.scrollView setContentOffset:CGPointMake(x, 0) animated:YES];}#pragma mark - 滚动视图代理方法- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{    // 根据contentOffset计算页数    NSInteger page = scrollView.contentOffset.x / scrollView.bounds.size.width;    self.pageControl.currentPage = page;}- (void)scrollViewDidScroll:(UIScrollView *)scrollView{    if (self.timer)    {        return;    }    self.pageControl.currentPage = (scrollView.contentOffset.x + scrollView.frame.size.width * 0.5) / scrollView.frame.size.width;}//手动滑动开始时，停止自动滚动- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{    if (self.autoScroll) {        [self.timer invalidate];        self.timer = nil;    }}//手动滑动停止时，开启自动滚动- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate{    if (self.autoScroll) {        [self startTimer];    }}#pragma mark 懒加载-(NSMutableArray *)dataArr{    if (!_dataArr) {        _dataArr = [[NSMutableArray alloc]init];    }    return _dataArr;}@end

@interface CarouselModel : NSObject//轮播图的地址@property(copy,nonatomic) NSString *imageUrl;//超链接内容的地址@property(copy,nonatomic) NSString *contentUrl;//文本显示内容@property(copy,nonatomic) NSString *labelText;@end

VC中使用

self.automaticallyAdjustsScrollViewInsets = NO;        NSMutableArray *dataList = [[NSMutableArray alloc]init];    NSMutableArray *dataArr = [[NSMutableArray alloc]initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"carouselArr.plist" ofType:nil]];    for (NSDictionary *dic in dataArr) {        CarouselModel *model = [[CarouselModel alloc]init];        model.imageUrl = [dic objectForKey:@"imageUrl"];        model.contentUrl = [dic objectForKey:@"contentUrl"];        model.labelText = [dic objectForKey:@"textLable"];        [dataList addObject:model];    }        CarouselView1 *view1 = [[CarouselView1 alloc]initWithFrameAndData:CGRectMake(20, 100, self.view.frame.size.width - 40, (self.view.frame.size.width - 40) * 0.5) data:dataList];    view1.delegate = self;//    开启自动滚动    [view1 startAutoScroll];    [self.view addSubview:view1];