用法 (作者离职，求一份工作)
- 只需要一个urlString数组，即可从后端服务器获取图片，并实现图片轮播
先看看效果
优化版图片浏览器.gif
使用条件
- 先导入SD_WebImage框架
- 将WHCircleImageView、WHCirCleImageViewCell类导入项目（具体代码见下面）
代码
- WHCircleImageView.h
#import <UIKit/UIKit.h>
@interface WHCircleImageView : UICollectionView
//提供一个接口
-(instancetype)initWithFrame:(CGRect)frame AndImageUrlArray:(NSArray *)ImageUrlArray view:(UIView *)view;
@end
- WHCircleImageView.m
#import "WHCircleImageView.h"
#import "WHCirCleImageViewCell.h"
#import "UIImageView+WebCache.h"
//多少秒翻动一次图片
#define changeImageTime 1.5
//pageControl的中心点位置
#define pageControlPosition CGPointMake(CGRectGetMaxX(frame)/2, CGRectGetMaxY(frame)-20)
@interface WHCircleImageView ()<UICollectionViewDelegate,UICollectionViewDataSource>
//接受传来的ImageUrlArray
@property(nonatomic,strong)NSArray *ImageUrlArray;
//存储下载的图片
@property(nonatomic,strong)NSArray *imageViewArray;
// 当前显示图片的索引
@property (nonatomic, assign) NSInteger currentIndex;
//提供一个timer，让其自动循环播放
@property(nonatomic,strong)NSTimer *timer;
//全局属性图片滚动到的位置
@property (nonatomic,assign)NSInteger index;
@property (nonatomic,strong)UIPageControl * page;
@end
@implementation WHCircleImageView
-(instancetype)initWithFrame:(CGRect)frame AndImageUrlArray:(NSArray *)ImageUrlArray view:(UIView *)view{
//创建流水布局
UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
layout.itemSize = CGSizeMake(frame.size.width, frame.size.height);
layout.minimumInteritemSpacing = 0;
layout.minimumLineSpacing = 0;
layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
//创建collectionView
self = [[WHCircleImageView alloc] initWithFrame:frame collectionViewLayout:layout];
//注册cell
[self registerClass:[WHCirCleImageViewCell class] forCellWithReuseIdentifier:@"circle"];
self.pagingEnabled = YES;
self.showsHorizontalScrollIndicator = NO;
self.delegate =self;
self.dataSource = self;
[self addTimer];
self.index = self.ImageUrlArray.count*30;
NSIndexPath * indexPath = [NSIndexPath indexPathForItem:self.index inSection:0];
//默认一开始滚动到第1000张图片的位置
[self scrollToItemAtIndexPath:indexPath atScrollPosition:UICollectionViewScrollPositionNone animated:YES];
self.ImageUrlArray = ImageUrlArray;
//添加pageController
UIPageControl * page = [self createPage];
//根据图片张数获取page的宽高
CGSize pageSize = [page sizeForNumberOfPages:self.ImageUrlArray.count];
page.frame = CGRectMake(0, 0, pageSize.width, pageSize.height);
page.center = pageControlPosition;
self.page = page;
[view addSubview:self];
[view addSubview:page];
return self;
}
//计时器的方法 自动滚动图片
-(void)changeImage
{
//调用计时器方法是 让图片索引++ 滚动图片
self.index++;
NSIndexPath *indexpath = [NSIndexPath indexPathForItem:self.index inSection:0];
[self scrollToItemAtIndexPath:indexpath atScrollPosition:UICollectionViewScrollPositionNone animated:YES];
self.page.currentPage = self.index%self.imageViewArray.count;
}
// MARK:数据源方法
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
return 30000;
}
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
WHCirCleImageViewCell * cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"circle" forIndexPath:indexPath];
//取出图片赋值给cell
cell.UrlimageView = self.imageViewArray[indexPath.item%self.imageViewArray.count];
return cell;
}
//当手指拖动图片时
-(void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView
{
[self deleteTimer];
}
//滚动结束之后发送通知 让控制器接收通知 设置page的当前页数
-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
NSInteger index = scrollView.contentOffset.x/scrollView.bounds.size.width;
self.index = index;
self.page.currentPage = self.index%self.imageViewArray.count;
[self addTimer];
}
-(void)addTimer
{
NSTimer * timer = [NSTimer scheduledTimerWithTimeInterval:changeImageTime target:self selector:@selector(changeImage) userInfo:nil repeats:YES];
//添加到运行循环
[[NSRunLoop currentRunLoop] addTimer:timer forMode:NSDefaultRunLoopMode];
self.timer = timer;
}
-(void)deleteTimer
{
[self.timer invalidate];
self.timer = nil;
}
//创建pageControl
-(UIPageControl *)createPage
{
//初始化方法
UIPageControl * page = [[UIPageControl alloc]init];
page.currentPage = 0;
page.numberOfPages = self.ImageUrlArray.count;
page.currentPageIndicatorTintColor = [UIColor orangeColor];
page.pageIndicatorTintColor = [UIColor cyanColor];
return page;
}
//当手指拖动图片时
//懒加载
-(NSArray *)imageViewArray{
NSMutableArray *tempArray = [NSMutableArray arrayWithCapacity:self.ImageUrlArray.count];
for (int i = 0; i < [_ImageUrlArray count]; i++) {
NSString *imageUrl = self.ImageUrlArray[i];
UIImageView *imageView = [[UIImageView alloc] initWithFrame:self.frame];
UIImage *image = [UIImage imageNamed:@"new_feature_finish_button_highlighted"];
[imageView sd_setImageWithURL:[NSURL URLWithString:imageUrl] placeholderImage:image];
[tempArray addObject:imageView];
}
return tempArray;
}
@end
- WHCirCleImageViewCell.h
#import <UIKit/UIKit.h>
@interface WHCirCleImageViewCell : UICollectionViewCell
//接受外部的图片
@property(nonatomic,strong)UIImageView *UrlimageView;
@end
- WHCirCleImageViewCell.m
#import "WHCirCleImageViewCell.h"
@interface WHCirCleImageViewCell ()
@property(nonatomic,strong)UIImageView *imageView;
@end
@implementation WHCirCleImageViewCell
-(void)setUrlimageView:(UIImageView *)UrlimageView{
_UrlimageView = UrlimageView;
self.imageView = UrlimageView;
[self.contentView addSubview:UrlimageView];
}
@end
- Controller中掉用
#import "ViewController.h"
#import "WHCircleImageView.h"
#define Application_Frame [[UIScreen mainScreen] bounds]
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
NSArray *testArr = @[@"http://img4.duitang.com/uploads/item/201303/17/20130317090104_jF8iH.jpeg",@"http://imgsrc.baidu.com/forum/pic/item/0e2442a7d933c895d8064c31d11373f08202007b.jpg",@"http://d.3987.com/Qhyrz_130520/004.jpg"];
WHCircleImageView *circleImageView = [[WHCircleImageView alloc] initWithFrame:CGRectMake(0, 0, Application_Frame.size.width, 250) AndImageUrlArray:testArr view:self.view];
#pragma 不要再掉用下面方法了，在上面的方法内部已经将circleImageView添加到self.view上过了
// [self.view addSubview:circleImageView];
}
@end
