关于UIScrollView图片浏览的例子有很多,之前也写过类似方面的文章,关于UIScrollView的图片循环在新闻类的App基本上是比较常见的一种情况就是图片浏览,然后根据不同的图片显示不同的内容显示不同的图片的介绍,因为属于比较常用的空间,先来看下需要实现的效果:
小圆点指示器是通过UIPageControl实现的,图片循环通过UIScrollView实现:
-(UIPageControl *)pageControl{ if (!_pageControl) { _pageControl=[[UIPageControl alloc]initWithFrame:CGRectMake(0, 0, 150, 40)]; _pageControl.currentPage=0; _pageControl.pageIndicatorTintColor=[UIColor whiteColor]; _pageControl.currentPageIndicatorTintColor=[UIColor greenColor]; } return _pageControl; } -(UIScrollView *)scrollView{ if (!_scrollView) { CGRect screenRect=[[UIScreen mainScreen]bounds]; _scrollView=[[UIScrollView alloc]initWithFrame:CGRectMake(0, 64, CGRectGetWidth(screenRect), CGRectGetHeight(screenRect)-164)]; [_scrollView setBounces:NO]; [_scrollView setShowsHorizontalScrollIndicator:NO]; [_scrollView setPagingEnabled:YES]; _scrollView.delegate=self; } return _scrollView; }
关于分页的页面配置以及页数Label的设置:
self.screenRect=[[UIScreen mainScreen]bounds]; CGFloat width=self.scrollView.bounds.size.width; CGFloat height=self.scrollView.bounds.size.height; self.imageArr=@[@"girl0.jpg",@"girl1.jpg",@"girl2.jpg"]; [self.scrollView setContentSize:CGSizeMake([self.imageArr count]*width, height)]; for (NSInteger i=0; i<[self.imageArr count]; i++) { UIImageView *imageView=[[UIImageView alloc]initWithFrame:CGRectMake(i*width, 0, width,height)]; imageView.image=[UIImage imageNamed:self.imageArr[i]]; imageView.contentMode=UIViewContentModeScaleToFill; [self.scrollView addSubview:imageView]; } [self.view addSubview:self.scrollView]; self.pageControl.numberOfPages=[self.imageArr count]; self.pageControl.center=CGPointMake(self.scrollView.center.x, CGRectGetMaxY(self.scrollView.bounds)+50); [self.view addSubview:self.pageControl]; self.pageLabel.text=[NSString stringWithFormat:@"%d/%lu",1,[self.imageArr count]]; [self.view addSubview:self.pageLabel];
实现UIScrollViewDelegate中scrollViewDidEndDecelerating的方法:
//博客园-FlyElephant 原文地址:http://www.cnblogs.com/xiaofeixiang/ -(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{ if (self.currentPage==[self.imageArr count]-1) { self.currentPage=0; self.scrollView.contentOffset=CGPointMake(0, 0); }else{ self.currentPage=scrollView.contentOffset.x/CGRectGetWidth(self.screenRect); } self.pageControl.currentPage=self.currentPage; [self.pageLabel setText:[NSString stringWithFormat:@"%ld/%lu",self.currentPage+1,[self.imageArr count]]]; }
简单的UIScrollView实现基本上ok了,当然关于UIScrollView根据不同场景去实现不同的功能代码量比这肯定更复杂~