轮播图

#import"ViewController.h"

@interfaceViewController()

//滑动视图UIScrollView,自带了可滑动功能

@property(nonatomic,strong)

UIScrollView*scrollView;

@end

@implementationViewController

#define screenWidth[UIScreen mainScreen].bounds.size.width

#define screenHeight[UIScreen mainScreen].bounds.size.height

- (void)viewDidLoad {

[superviewDidLoad];

//创建初始化滑动视图

self.scrollView= [[UIScrollViewalloc]initWithFrame:[UIScreenmainScreen].bounds];

for(NSIntegeri =0; i <6; i++) {

//根据i循环创建UIImageView，在添加到滑动视图scrollView上面

UIImageView*imageView = [[UIImageViewalloc]initWithFrame:CGRectMake(i*screenWidth,0,screenWidth,screenHeight)];

NSString*imageName =nil;

if(i==5)

{

imageName =@"1.jpg";

}

else{

imageName = [NSStringstringWithFormat:@"%ld.jpg",i+1];

}

//加载响应图片

UIImage*image = [UIImageimageNamed:imageName];

//设置图片

imageView.image= image;

//将imageview添加到滑动视图上面

[self.scrollViewaddSubview:imageView];

}

//添加滑动视图到屏幕上

[self.viewaddSubview:self.scrollView];

//设置滑动试图的滑动区域contenSize

self.scrollView.contentSize=CGSizeMake(6*screenWidth,screenHeight);

//整屏翻转

self.scrollView.pagingEnabled=YES;

//边界回弹

self.scrollView.bounces=NO;

//设置代理，代理是负责监听滑动试图整个滑动过程的

self.scrollView.delegate=self;

}

//滑动视图滑动的时候调用

- (void)scrollViewDidScroll:(UIScrollView*)scrollView;{

//contene)ffset是访问到了滑动视图的偏移量，包含了X和Y轴的偏移量

//sentConteneOffset:animated:

//{NSLog(@"偏移量,x = %f,y = %f",scrollView.contentOffset.x,scrollView.contentOffset.y);

}

//scrollView结束减速（停止）

- (void)scrollViewDidEndDecelerating:(UIScrollView*)scrollView

{

//判断是否为最后一张

NSIntegerindex = scrollView.contentOffset.x/screenWidth;

//==5表示最后一张

if(index==5) {

[scrollViewsetContentOffset:CGPointMake(0,0)animated:NO];

}

//开启一个计时器

//TimeInterval:时间间隔

//每隔一段时间间隔，target会去执行selector这个方法

[NSTimer

scheduledTimerWithTimeInterval:2target:selfselector:@selector(turnToNextImage)userInfo:nilrepeats:YES];

}

//定时器触发的方法；跳转到下一张

-(void)turnToNextImage

{

//获取当前第几张图片

NSIntegerindex =self.scrollView.contentOffset.x/screenWidth;

//跳转到下一张(设置偏移量)

[self.scrollViewsetContentOffset:CGPointMake((index+1)*screenWidth,0)animated:YES];

}

//滑动结束时候调用

- (void)scrollViewDidEndScrollingAnimation:(UIScrollView*)scrollView;

{

//现获取当前下标

NSIntegerindex =self.scrollView.contentOffset.x/screenWidth;if(index==5) {

[scrollViewsetContentOffset:CGPointMake(0,0)animated:NO];

}

}

- (void)didReceiveMemoryWarning{

[superdidReceiveMemoryWarning];

// Dispose of any resources that can be

recreated.

}

@end

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