iOS UIScrollView 实现轮播图

利用UIScrollView实现轮播图 , 需要三个ImageView轮流切换,具体原理就不讲解了.

具体实现代码如下:

<span style="font-size:24px;">////  ViewController.m//  PhotosShowDemo////  Created by 帝炎魔 on 16/5/29.//  Copyright © 2016年 帝炎魔. All rights reserved.//#import "ViewController.h"#define kWidth [UIScreen mainScreen].bounds.size.width#define kHeitht [UIScreen mainScreen].bounds.size.height#define kRedColor [UIColor redColor]#define kWhitColor [UIColor yellowColor]#define kBlueColor [UIColor blueColor]#define kGreenColor [UIColor greenColor]#define kBrownColor [UIColor brownColor]@interface ViewController () <UIScrollViewDelegate>@property (nonatomic, strong) UIScrollView *scrollView;@property (nonatomic, strong) UIPageControl *pageControl;@property (nonatomic, strong) UIView *leftView;@property (nonatomic, strong) UIView *currentView;@property (nonatomic, strong) UIView *rightView;@property (nonatomic, assign) int viewCount;@property (nonatomic, assign) int currentViewIndex;@property (nonatomic, copy) NSArray *viewColorArray;@property (nonatomic, copy) NSTimer *timer;@property (nonatomic, assign) BOOL isScroll;@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];        self.viewColorArray = @[kRedColor, kBlueColor, kBrownColor, kWhitColor, kGreenColor ];                // 添加scrollView    [self.view addSubview:self.scrollView];    [self.view addSubview:self.pageControl];        [self loadImageView];        // 创建定时器 实现轮播    [self zidong];    // Do any additional setup after loading the view, typically from a nib.}// 开启定时器- (void)zidong{    _timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(nextPage) userInfo:NULL repeats:YES];}// 定时器的方法-(void)nextPage{    _isScroll = YES;    int rightCout;    [_scrollView setContentOffset:CGPointMake(kWidth * 2, 0)animated:YES];           _currentViewIndex = (_currentViewIndex + 1) % 5;    _currentView.backgroundColor = _viewColorArray[_currentViewIndex];       rightCout = (_currentViewIndex + 1) % 5;            _rightView.backgroundColor = _viewColorArray[rightCout];       _pageControl.currentPage = _currentViewIndex;    [_scrollView setContentOffset:CGPointMake(kWidth, 0) animated:NO];        }// 添加滑动视图- (UIScrollView *)scrollView{    if (!_scrollView) {        _scrollView = [[UIScrollView alloc] init];                _scrollView.frame = CGRectMake(0, 0, kWidth, kHeitht);                _scrollView.contentSize = CGSizeMake(kWidth * 3, kHeitht);        _scrollView.pagingEnabled = YES;                _scrollView.delegate = self;       [_scrollView setContentOffset:CGPointMake(kWidth, 0)];        _scrollView.showsVerticalScrollIndicator = NO;        _scrollView.showsHorizontalScrollIndicator = NO;    }    return _scrollView;}// 添加按钮-(UIPageControl *)pageControl{    if (!_pageControl) {        _pageControl = [[UIPageControl alloc] init];        _pageControl.frame = CGRectMake(0, kHeitht - 100, kWidth, 30);        _pageControl.currentPage = _currentViewIndex;        _pageControl.numberOfPages = 5;        _pageControl.pageIndicatorTintColor = kBlueColor;        _pageControl.currentPageIndicatorTintColor = kWhitColor;    }    return _pageControl;}// 加载图片- (void)loadImageView{    _leftView = [[UIView alloc] init];    _leftView.backgroundColor = _viewColorArray[4];    _leftView.frame = CGRectMake(0, 0, kWidth, kHeitht);    [_scrollView addSubview:_leftView];        _currentView = [[UIView alloc] initWithFrame:CGRectMake(kWidth, 0, kWidth, kHeitht)];    _currentView.backgroundColor = _viewColorArray[0];    [_scrollView addSubview:_currentView];        _rightView = [[UIView alloc] initWithFrame:CGRectMake(2 * kWidth, 0, kWidth, kHeitht)];    _rightView.backgroundColor = _viewColorArray[1];    [_scrollView addSubview:_rightView];        _currentViewIndex = 0;    }#pragma mark ---- 滚动将要停止的时候- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{    // 滚动视图停止减速    // contentOffset 偏移量    // 开启定时器    if (_isScroll == NO) {        [self zidong];        _isScroll = YES;    }            [self loadData];        _pageControl.currentPage = _currentViewIndex;    [_scrollView setContentOffset:CGPointMake(kWidth, 0)];            // UIControl 响应的控件 的父类   //  UIControl        }-(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{    // 移除定时器         [self.timer invalidate];    if (_isScroll == YES) {         scrollView.contentOffset = CGPointMake(kWidth, 0);        _currentView.backgroundColor = _viewColorArray[_currentViewIndex];    }    _isScroll = NO;       // _currentView = _viewColorArray[_currentViewIndex];}- (void)loadData{    if (_scrollView.contentOffset.x > kWidth) {        NSLog(@"右滑动");        _currentViewIndex = (_currentViewIndex + 1) % 5;            } else if (_scrollView.contentOffset.x < kWidth) {        NSLog(@"左滑动");        _currentViewIndex = (_currentViewIndex + 4 ) % 5;    }    _currentView.backgroundColor = _viewColorArray[_currentViewIndex];    _leftView.backgroundColor = _viewColorArray[(_currentViewIndex + 4) % 5];    _rightView.backgroundColor = _viewColorArray[(_currentViewIndex + 1) % 5];    }- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end</span>