iOS開發--圖片輪播

直接上代碼了，比較簡單。演示下載地址：Demo

//
//  UYViewController.m
//  圖片輪播器
//
//  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) {
        //若是爲空，建立一個
        _scrollView=[[UIScrollView alloc] initWithFrame:CGRectMake(10, 20, 300, 130)];
        _scrollView.backgroundColor=[UIColor redColor];
        
        //取消彈簧效果
        _scrollView.bounces=NO;
        
        // 取消水平滾動條
        _scrollView.showsHorizontalScrollIndicator = NO;
        _scrollView.showsVerticalScrollIndicator = NO;
        
        // 要分頁
        _scrollView.pagingEnabled = YES;
        
        // contentSize
        _scrollView.contentSize = CGSizeMake(kImageCount * _scrollView.bounds.size.width, 0);
        
        // 設置代理
        _scrollView.delegate = self;
        
        [self.view addSubview:_scrollView];
                     
    }
    return _scrollView;

}

- (UIPageControl *)pageControl
{
    if (_pageControl == nil) {
        // 分頁控件，本質上和scrollView沒有任何關係，是兩個獨立的控件
        _pageControl = [[UIPageControl alloc] init];
        // 總頁數
        _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);
        
        // 設置顏色
        _pageControl.pageIndicatorTintColor = [UIColor redColor];
        _pageControl.currentPageIndicatorTintColor = [UIColor blackColor];
        
        [self.view addSubview:_pageControl];
        
        // 添加監聽方法
        /** 在OC中，絕大多數"控件"，均可以監聽UIControlEventValueChanged事件，button除外" */
        [_pageControl addTarget:self action:@selector(pageChanged:) forControlEvents:UIControlEventValueChanged];
    }
    return _pageControl;
}

// 分頁控件的監聽方法
- (void)pageChanged:(UIPageControl *)page
{
    // 根據頁數，調整滾動視圖中的圖片位置 contentOffset
    CGFloat x = page.currentPage * self.scrollView.bounds.size.width;
    [self.scrollView setContentOffset:CGPointMake(x, 0) animated:YES];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
	//設置圖片
    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];
    }
    //計算imageView
    [self.scrollView.subviews enumerateObjectsUsingBlock:^(UIImageView *imageView, NSUInteger idx, BOOL *stop) {
        // 調整x => origin => frame
        CGRect frame = imageView.frame;
        frame.origin.x = idx * frame.size.width;
        
        imageView.frame = frame;
    }];
    
    // 分頁初始頁數爲0
    self.pageControl.currentPage = 0;
    
    // 啓動時鐘
    [self startTimer];
    
}

- (void)startTimer
{
    self.timer = [NSTimer timerWithTimeInterval:2.0 target:self selector:@selector(updateTimer) userInfo:nil repeats:YES];
    // 添加到運行循環
    [[NSRunLoop currentRunLoop] addTimer:self.timer forMode:NSRunLoopCommonModes];
}

- (void)updateTimer
{
    // 頁號發生變化
    // (當前的頁數 + 1) % 總頁數
    int page = (self.pageControl.currentPage + 1) % kImageCount;
    self.pageControl.currentPage = page;

    // 調用監聽方法，讓滾動視圖滾動
    [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
// 滾動視圖停下來，修改頁面控件的小點（頁數）
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
    // 計算頁數
    int page = scrollView.contentOffset.x / scrollView.bounds.size.width;
    
    self.pageControl.currentPage = page;
}

/**
 修改時鐘所在的運行循環的模式後，抓不住圖片
 
 解決方法：抓住圖片時，中止時鐘，送售後，開啓時鐘
 */
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
    // 中止時鐘，中止以後就不能再使用，若是要啓用時鐘，須要從新實例化
    [self.timer invalidate];
}

- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
    [self startTimer];
}


@end