iOS开发--图片轮播

直接上代码了，比较简单。演示下载地址：Demo

//

//  UYViewController.m

//  图片轮播器

//

//  Created by jiangys on 15/5/23.

//  Copyright (c) 2015年 uxiaoyuan. All rights reserved.

//



#import "UYViewController.h"

#define kImageCount 5



@interface UYViewController ()<UIScrollViewDelegate>



@property (nonatomic,strong) UIScrollView *scrollView;

@property (nonatomic,strong) UIPageControl *pageControl;



@property (nonatomic, strong) NSTimer *timer;



@end



@implementation UYViewController



-(UIScrollView *)scrollView

{

    if (_scrollView==nil) {

        //如果为空，创建一个

        _scrollView=[[UIScrollView alloc] initWithFrame:CGRectMake(10, 20, 300, 130)];

        _scrollView.backgroundColor=[UIColor redColor];

        

        //取消弹簧效果

        _scrollView.bounces=NO;

        

        // 取消水平滚动条

        _scrollView.showsHorizontalScrollIndicator = NO;

        _scrollView.showsVerticalScrollIndicator = NO;

        

        // 要分页

        _scrollView.pagingEnabled = YES;

        

        // contentSize

        _scrollView.contentSize = CGSizeMake(kImageCount * _scrollView.bounds.size.width, 0);

        

        // 设置代理

        _scrollView.delegate = self;

        

        [self.view addSubview:_scrollView];

                     

    }

    return _scrollView;



}



- (UIPageControl *)pageControl

{

    if (_pageControl == nil) {

        // 分页控件，本质上和scrollView没有任何关系，是两个独立的控件

        _pageControl = [[UIPageControl alloc] init];

        // 总页数

        _pageControl.numberOfPages = kImageCount;

        // 控件尺寸

        CGSize size = [_pageControl sizeForNumberOfPages:kImageCount];

        

        _pageControl.bounds = CGRectMake(0, 0, size.width, size.height);

        _pageControl.center = CGPointMake(self.view.center.x, 130);

        

        // 设置颜色

        _pageControl.pageIndicatorTintColor = [UIColor redColor];

        _pageControl.currentPageIndicatorTintColor = [UIColor blackColor];

        

        [self.view addSubview:_pageControl];

        

        // 添加监听方法

        /** 在OC中，绝大多数"控件"，都可以监听UIControlEventValueChanged事件，button除外" */

        [_pageControl addTarget:self action:@selector(pageChanged:) forControlEvents:UIControlEventValueChanged];

    }

    return _pageControl;

}



// 分页控件的监听方法

- (void)pageChanged:(UIPageControl *)page

{

    // 根据页数，调整滚动视图中的图片位置 contentOffset

    CGFloat x = page.currentPage * self.scrollView.bounds.size.width;

    [self.scrollView setContentOffset:CGPointMake(x, 0) animated:YES];

}



- (void)viewDidLoad

{

    [super viewDidLoad];

	//设置图片

    for (int i=0; i<kImageCount; i++) {

        NSString *imageName=[NSString stringWithFormat:@"img_%02d",i+1];

        UIImage *image=[UIImage imageNamed:imageName];

        

        UIImageView *imageView=[[UIImageView alloc] initWithFrame:self.scrollView.bounds];

        imageView.image=image;

        

        [self.scrollView addSubview:imageView];

    }

    //计算imageView

    [self.scrollView.subviews enumerateObjectsUsingBlock:^(UIImageView *imageView, NSUInteger idx, BOOL *stop) {

        // 调整x => origin => frame

        CGRect frame = imageView.frame;

        frame.origin.x = idx * frame.size.width;

        

        imageView.frame = frame;

    }];

    

    // 分页初始页数为0

    self.pageControl.currentPage = 0;

    

    // 启动时钟

    [self startTimer];

    

}



- (void)startTimer

{

    self.timer = [NSTimer timerWithTimeInterval:2.0 target:self selector:@selector(updateTimer) userInfo:nil repeats:YES];

    // 添加到运行循环

    [[NSRunLoop currentRunLoop] addTimer:self.timer forMode:NSRunLoopCommonModes];

}



- (void)updateTimer

{

    // 页号发生变化

    // (当前的页数 + 1) % 总页数

    int page = (self.pageControl.currentPage + 1) % kImageCount;

    self.pageControl.currentPage = page;



    // 调用监听方法，让滚动视图滚动

    [self pageChanged:self.pageControl];

}



- (void)didReceiveMemoryWarning

{

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.s

    

}







#pragma mark - ScrollView的代理方法

// 滚动视图停下来，修改页面控件的小点（页数）

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView

{

    // 计算页数

    int page = scrollView.contentOffset.x / scrollView.bounds.size.width;

    

    self.pageControl.currentPage = page;

}



/**

 修改时钟所在的运行循环的模式后，抓不住图片

 

 解决方法：抓住图片时，停止时钟，送售后，开启时钟

 */

- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView

{

    // 停止时钟，停止之后就不能再使用，如果要启用时钟，需要重新实例化

    [self.timer invalidate];

}



- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate

{

    [self startTimer];

}





@end