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iOS图片轮播器banner封装(新增swift版本)

iOS图片轮播器banner封装(新增swift版本)

作者: 打瞌睡de小男孩 | 来源:发表于2016-12-19 20:33 被阅读199次

    最近闲来无事,封装了一个无限图片轮播器,基于collectionView完成,抽取了两个API,一个是创建轮播器,一个是点击图片的跳转,使用的话,直接把JZLCycleView这个文件夹拖进项目,调用API就完成了,非常简单
    更新:
    2016.12.21 解决控制器被销毁时,timer不被释放造成的内存泄漏

    1.无限轮播思路:
    建了图片数量*3个数的cell,然后去一直显示中间的cell,到最后一组的第一个,无动画滚动到中间一组的第一个,到第一组的最后一个,无动画滚动到中间一组的最后一个
    2.调用的方法,使用直接调用API

    
    
        _cycleView = [JZLCycleView cycleCollectionViewWithFrame:CGRectMake(0, 0, JZLScreenWidth, JZLCycleViewHeight) imageArray:arrTemp PlaceholderImage:[UIImage imageNamed:@"placeholderImage"]];
    //小圆点颜色设置,自己根据需求更改,默认黑色和白色
        _cycleView.pageControl.pageIndicatorTintColor = [UIColor orangeColor];
        _cycleView.pageControl.currentPageIndicatorTintColor = [UIColor whiteColor];
    //如果要跳转记得遵守协议,设置代理
        _cycleView.delegate = self;
        _cycleView.clickItemBlock = ^(NSInteger index){
            NSLog(@"%ld",(long)index);
        };
        [self.view addSubview:_cycleView];
    

    2.1跳转这一块封装了两个,一个block,一个代理,个人认为代理更清晰一些

    //block跳转
        _cycleView.clickItemBlock = ^(NSInteger index){
            NSLog(@"%ld",(long)index);
        };
    
    //代理跳转
    - (void)selectItemAtIndex:(NSInteger)index {
        NSLog(@"%ld",index);
    }
    

    3.实现
    1.初始化轮播器,这里抽取了两个,一个是加载本地图片,一个是加载网路url,一般开发中第二个用的比较多

    
    
    
    
    /**
     初始化实例
    
     @param frame 图片轮播器frame
     @param imageArray 本地图片数组(可传图片url和本地图片,自动判断)
     @param placeholderImage 占位图
     @return 图片轮播器
     */
    + (instancetype)cycleCollectionViewWithFrame: (CGRect)frame imageArray: (NSArray *)imageArray PlaceholderImage: (UIImage *)placeholderImage;
    

    2.主要的就是去完成collectionView

    
    
    //设置collectionView
    - (void)setupCollcetionView {
        //collcetionView
        UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];
        UICollectionView *collectionView = [[UICollectionView alloc] initWithFrame:self.bounds collectionViewLayout:flowLayout];
        flowLayout.itemSize = CGSizeMake(self.bounds.size.width, self.bounds.size.height);
        flowLayout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
        flowLayout.minimumLineSpacing = 0;
        collectionView.pagingEnabled = YES;
        collectionView.bounces = NO;
        collectionView.showsHorizontalScrollIndicator = NO;
        collectionView.delegate = self;
        collectionView.dataSource = self;
        [collectionView registerClass:[JZLCollectionViewCell class] forCellWithReuseIdentifier: reuseID];
        [self addSubview:collectionView];
        self.collectionView = collectionView;
        //pageControl
        self.pageControl = [[UIPageControl alloc] initWithFrame:CGRectMake(self.bounds.size.width / 2 - 50, self.bounds.size.height - 20, 100, 20)];
        //默认一张,加载图片后自动更新
        self.pageControl.numberOfPages = 1;
        self.pageControl.currentPage = 0;
        [self addSubview:self.pageControl];
        
    }
    

    3.添加定时器以及手动滚动和自动滚动的切换

    
    
    //设置页码
    - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
        self.pageControl.currentPage = (NSInteger)(scrollView.contentOffset.x / scrollView.bounds.size.width)%self.imageArray.count;
    }
    
    //添加定时器
    - (void)addTimer {
        self.timer = [NSTimer scheduledTimerWithTimeInterval:automaticTime target:self selector:@selector(automaticScrollCollectionCell) userInfo:nil repeats:YES];
        [[NSRunLoop currentRunLoop] addTimer:self.timer forMode:NSRunLoopCommonModes];
    }
    
    //删除定时器
    - (void)deleteTimer {
        [self.timer invalidate];
        self.timer = nil;
    }
    //自动滚动
    - (void)automaticScrollCollectionCell {
        self.index++;
        if (self.imageArray.count == 0) {
            return;
        }else {
            NSIndexPath *indexPath = [NSIndexPath indexPathForItem:self.index inSection:0];
            [self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:0 animated:YES];
            
            if (indexPath.row == self.imageArray.count * 2) {
                dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
                    NSIndexPath *indexPath = [NSIndexPath indexPathForItem:self.imageArray.count inSection:0];
                    [self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:0 animated:NO];
                });
                
            }
            
            self.pageControl.currentPage = self.index % self.imageArray.count ;
        }
    
    }
    //手动滚动时删除定时器
    - (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView {
        [self deleteTimer];
        if (self.imageArray.count == 0) {
            return;
        }else {
            if (self.index == self.imageArray.count - 1) {
                [self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:self.imageArray.count * 2 - 1 inSection:0] atScrollPosition:0 animated:NO];
            }
            
            if (self.index == self.imageArray.count * 2) {
                [self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:self.imageArray.count inSection:0] atScrollPosition:0 animated:NO];
            }
        }
    
        
        
    }
    //停止滚动时打开定时器
    - (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate {
        [self addTimer];
    }
    - (void)scrollViewDidScroll:(UIScrollView *)scrollView {
        self.index = (NSInteger)(scrollView.contentOffset.x / scrollView.bounds.size.width);
        
    }
    

    git地址:https://github.com/allenjzl/JZLCycleView.git
    swift版本:https://github.com/allenjzl/JZLCycleView_Swift.git
    下载图片用了sdwebImage,demo的话报错记得icocoaPods里面install一下,如果大家发现有崩溃或者问题,请留言,谢谢

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