一、UIScrollView继承于UIView，它还有一个常用的子类UITableView；今天只介绍UIScrollView的基本使用：首先介绍一下它的几个常用属性，这里不做过多属性的介绍，有关其属性的相关信息可以command+鼠标左键，进入系统中自行查看
CGSize contentSize：用于设置滚动范围的，在创建一个UIScrollView对象之后，除了设置对象的frame还必须设置其滚动范围（CGSize contentSize）；CGPoint contentOffSet：当前显示的范围；CGFloat minimumZoomScale：最小缩放最小比例（默认是1不进行缩放）；CGFloat maximumZoomScale：最大缩放最小比例（默认是1不进行缩放）;self.scrollView.showsHorizontalScrollIndicator = NO;//是否设置水平方向的滚动条；self.scrollView.showsVerticalScrollIndicator = NO;//是否设置垂直方向的滚动条等等；滚动所用的方法别忘记设置协议<UIScrollViewDelegate>
下面举了简单的例子：实现多张图片的滑动（添加了UIPageControl）及缩放，图片滑过之后尺寸自动还原。
AppDelegate.m文件中：
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch. self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds]; self.window.backgroundColor = [UIColor whiteColor]; [self.window makeKeyAndVisible]; self.window.rootViewController = [[RootViewController alloc] init]; return YES;}RootViewController.m#import "RootViewController.h"
#import "RootView.h"@interface RootViewController ()<UIScrollViewDelegate>//自定义视图替换控制器自带的View，提升程序的灵活性、可移植性@property (nonatomic, strong) RootView *rootView;@end@implementation RootViewController-(void)loadView { //自定义视图替换控制器自带的View，提升程序的灵活性、可移植性 self.rootView = [[RootView alloc] initWithFrame:[UIScreen mainScreen].bounds]; self.view = self.rootView;}- (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. //给“scrollView”设置代理 self.rootView.scrollView.delegate = self; //给pageControl添加方法 [self.rootView.pageControl addTarget:self action:@selector(pageControlAction:) forControlEvents:UIControlEventValueChanged]; //设置初始尺寸 self.rootView.scrollView.zoomScale = 1; //给每一个“scroll”设置代理 for (int i = 10; i < 15; i++) { UIScrollView *scroll = [self.rootView.scrollView viewWithTag:i]; scroll.zoomScale = 1; scroll.delegate = self; }}//返回进行缩放的“scroll”- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView { if (scrollView != self.rootView.scrollView) { return [scrollView.subviews objectAtIndex:0]; }else return nil;}//设置pageControl，图片向后滑动一张，pageControl向后动一下-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{ NSInteger index = scrollView.contentOffset.x / self.rootView.frame.size.width; self.rootView.pageControl.currentPage = index;}//上面pageControl方法的实现- (void)pageControlAction:(UIPageControl *)sender { NSInteger index = self.rootView.pageControl.currentPage; CGPoint points = CGPointMake(index * self.rootView.frame.size.width, 0); [UIView animateWithDuration:0.5 animations:^{ self.rootView.scrollView.contentOffset = points; }];}//将划过的图片还原-(void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView { if (scrollView == self.rootView.scrollView) { NSUInteger index = self.rootView.pageControl.currentPage; [[scrollView.subviews objectAtIndex:index] setZoomScale:1.0]; }}//图片缩放后居中-(void)scrollViewDidZoom:(UIScrollView *)scrollView { [scrollView.subviews objectAtIndex:0].center = self.rootView.center;}@endRootView.h
#import <UIKit/UIKit.h>
@interface RootView : UIView@property (nonatomic, strong) UIScrollView *scrollView;@property (nonatomic, strong) UIPageControl *pageControl;@endRootView.m
#import "RootView.h"
@implementation RootView-(instancetype)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; if (self) { [self addAllViews]; } return self;}- (void)addAllViews { //布局scrollView self.scrollView = [[UIScrollView alloc]initWithFrame:self.frame]; self.scrollView.backgroundColor = [UIColor redColor]; self.scrollView.pagingEnabled = YES; self.scrollView.minimumZoomScale = 0.2; self.scrollView.maximumZoomScale = 3; [self addSubview:self.scrollView]; self.scrollView.contentSize = CGSizeMake(self.frame.size.width * 5, 0); //创建多个scrollView，每张图片对应一个scrollView，进行缩放时，对每个图片所在的scrollView进行缩放， for (int i = 0; i < 5; i++) { UIScrollView *scrollViews = [[UIScrollView alloc] initWithFrame:CGRectMake(i * self.frame.size.width, 0, self.frame.size.width, self.frame.size.height)]; scrollViews.contentSize = CGSizeMake(self.frame.size.width, self.frame.size.height); scrollViews.tag = i + 10; scrollViews.minimumZoomScale = 0.2; scrollViews.maximumZoomScale = 3; NSString *str = [NSString stringWithFormat:@"%d.jpg", i + 1]; UIImageView *imageView = [[UIImageView alloc] init]; imageView.frame = CGRectMake(0, 0, scrollViews.frame.size.width, scrollViews.frame.size.height); imageView.image = [UIImage imageNamed:str]; [scrollViews addSubview:imageView]; [self.scrollView addSubview:scrollViews]; } //布局pageControl self.pageControl = [[UIPageControl alloc] initWithFrame:CGRectMake(0, self.frame.size.height - 40, self.frame.size.width, 40)]; self.pageControl.numberOfPages = 5; self.pageControl.backgroundColor = [UIColor grayColor]; [self addSubview:self.pageControl]; }@end