+ (instancetype)pageScroll

 {

     // NSStringFromClass 将类名转换成字符串,xib文件名和类名一样

     return [[[NSBundle mainBundle] loadNibNamed:NSStringFromClass(self) owner:nil options:nil] lastObject];

 }

 - (void)setImageNames:(NSArray *)imageNames

 {

     _imageNames = imageNames;

     // 添加图片

     for (int i =  ; i < imageNames.count; i ++ )

     {

         UIImageView *imageView = [[UIImageView alloc] init];

         imageView.image = [UIImage imageNamed:_imageNames[i]];

         [self.scrollView addSubview:imageView];

     }

     // 设置pageControl的页数

     self.pageControl.numberOfPages = _imageNames.count;

     // 设置scrollView是否在滚动到中间是自动滑向出现较多的那个页面

     self.scrollView.pagingEnabled = YES;

 }

 // layout ,计算控件的frame

 - (void)layoutSubviews

 {

     [super layoutSubviews];

     // 设置scrollView的frame

     self.scrollView.frame = self.bounds;

     //view的高度和宽度

     CGFloat viewW = self.scrollView.frame.size.width;

     CGFloat viewH = self.scrollView.frame.size.height;

     // view 的位置

     self.scrollView.contentSize = CGSizeMake(viewW * _imageNames.count, );

     // pageControl 的frame

     self.pageControl.frame = CGRectMake(viewW - , viewH - , , );

     // 计算图片的 frame

     for(int i = ; i < _imageNames.count ; i ++)

     {

         UIImageView *imageView = self.scrollView.subviews[i];

         imageView.frame = CGRectMake(i * viewW, , viewW, viewH);

     }

 }

 // 代理方法

 - (void)scrollViewDidScroll:(UIScrollView *)scrollView

 {

     // 设置当前页的索引

     self.pageControl.currentPage = (int)(scrollView.contentOffset.x / scrollView.frame.size.width + 0.5);

 }

 - (void)viewDidLoad {

     [super viewDidLoad];

     // Do any additional setup after loading the view, typically from a nib.

     // 加载ScrollView对象

     SLQPageScroll *scroll = [SLQPageScroll pageScroll];

     scroll.frame = CGRectMake(, , , );

     scroll.imageNames = @[@"img_00",@"img_01",@"img_02",@"img_03"];

     scroll.backgroundColor = [UIColor redColor];

     [self.view addSubview:scroll];

 }