需求：
1.点击卡片跳至中心
2.若点击的卡片已在中心，跳转控制器
3.滑动卡片至中心

实现效果：

iCarousel效果图.gif

具体实现：
遵守协议

@interface AXView () <iCarouselDelegate, iCarouselDataSource>
@property (nonatomic, strong) iCarousel *crousel;
// 单元格
@property (nonatomic, strong) AXViewItem *item;
@end

初始化

 _carousel = [[iCarousel alloc] initWithFrame:self.bounds];
// 设置滚动的模式
 _carousel.type = iCarouselTypeRotary;
// _carousel.scrollOffset = -100;
// 设置手势滑动的力度 deault 0.95
 _carousel.decelerationRate = 0.5;
 _carousel.delegate = self;
 _carousel.dataSource = self;
 [self addSubview:_carousel];

数据源方法

#pragma mark iCarouselDataSource
// 有多少项
- (NSInteger)numberOfItemsInCarousel:(iCarousel *)carousel{   
// 这里返回网络获取的数据数组个数 
return 3;
}
// 最大有多少个可以显示
- (NSUInteger)numberOfVisibleItemsInCarousel:(iCarousel *)carousel{      
  return 5;
}
//每一个的内容
- (UIView *)carousel:(iCarousel *)carousel viewForItemAtIndex:(NSInteger)index reusingView:(UIView *)view{    
    AXViewItem *item = nil;
    if (!view) {
        view = [[UIView alloc]initWithFrame:CGRectMake(0, 0, ScaleWidth(100),ScaleHeight(150))];
        item = [[AXViewItem alloc]initWithFrame:view.bounds];
        [view addSubview:item];
        item.tag = 100;
    }
    item = (AXViewItem *)[view viewWithTag:100];
    self.item = item;
    // 模型赋值
    // ...
    return item;
}

代理方法

#pragma mark - iCarouselDelegate
// MARK ：返回的宽度值是单元格item的可操作范围
-(CGFloat)carouselItemWidth:(iCarousel *)carousel{
    return ScaleWidth(79);
}
// 设置布局的选项：此处只用到下面两种
- (CGFloat)carousel:(iCarousel *)carousel valueForOption:(iCarouselOption)option withDefault:(CGFloat)value{
    
    switch (option)
    {
        case iCarouselOptionWrap:
        {
            // 是否旋转木马效果
            return YES;
        }
        case iCarouselOptionSpacing:
        {
            // 旋转半径，默认为0.25
            return value * 4.0f;
        }
        default:
        {
            return value;
        }
    }
}

didselect方法和拖拽结束时的方法单独抽离出来

- (void)carousel:(iCarousel *)carousel didSelectItemAtIndex:(NSInteger)index{
//    if (self.model.count > 0) {
//        Model *a = self.model[index];
//        self.item.model = a;
//    }
    if ( index == _ carousel.currentItemIndex) {
        // 因为多是view跳转控制器，所以此处用跟、根控制器为tabbarController演示
        UINavigationController *nav = (UINavigationController *)[UIApplication sharedApplication].keyWindow.rootViewController.rootViewController[0];
        AXTestViewController *vc = [[AXTestViewController alloc]init];    
        [nav pushViewController:vc animated:YES];      
    }
    // 测试用
    switch (index) {
        case 0:
        {
            NSLog(@"0======currentItemIndex:%ld",(long)carousel.currentItemIndex);           
        }
            break;
        case 1:
        {
            NSLog(@"1======currentItemIndex:%ld",(long)carousel.currentItemIndex);
        }
            break;
        case 2:
        {
            NSLog(@"2======currentItemIndex:%ld",(long)carousel.currentItemIndex);
        }
            break;
        default:
            break;
    } 
}
// 这个注释省略
- (void)carouselDidEndDecelerating:(iCarousel *)carousel{
    // 获取当前index
    // 模型赋值刷新控件等
    // 发送通知
}

最后销毁

- (void)dealloc
{
    //it's a good idea to set these to nil here to avoid
    //sending messages to a deallocated viewcontroller
     _carousel.delegate = nil;
     _carousel.dataSource = nil;
}