UIScrollView+UIPageControl+NSTimer实现图片的自动滑动以及用户可手动切换，UIPageControl可点击

UIScrollView+UIPageControl+NSTimer实现图片的自动滑动以及用户可手动切换，UIPageControl可点击

分类： iOS2013-03-27
20:24 187人阅读 评论(1) 收藏 举报

UIScrollViewUIPageControlNSTimer

作者太好了 原文链接http://blog.csdn.net/zhuiyi316/article/details/7756472

研究了一整天的成果，也借鉴了网上的一些资料，参考了http://huluwa.me/blog/ios-uiscrollview-loop/.的思想.主要实现了以下功能：

1.自动滑动图片，UIPageControl会随着图片滑动而改变；

2.用户可以手动切换图片，左右切换均可，当用户手动滑动图片时，图片停止自动切换；

3.实现了图片的循环播放；

4.UIPageControl可点击从而实现向左或右滑动，当用户点击UIPageControl时，图片不再自动切换；

直接上代码吧，不懂的后面还有工程和说明文档也一并附上(原来这个不能直接上传附件，要的就去资源页下载吧：http://download.csdn.net/detail/zhuiyi316/4434616)。

首先是.h文件，注意自己将IBOutlet和IBAction与storyBoard中拖入的控件相关联，我用的XCode4.3.1.

[plain] view
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#import <UIKit/UIKit.h>

@interface ViewController : UIViewController<UIScrollViewDelegate>

{

NSMutableArray *imageArray;//存放图片

NSTimer *myTimer;//定时器

}

@property(nonatomic,retain) IBOutlet UIScrollView *myScrollView;

@property(nonatomic,retain) IBOutlet

UIPageControl *pageControl;

-(IBAction)pageTurn:(UIPageControl *)sender;

@end

然后是.m文件，自己添加图片。#import <QuartzCore/QuartzCore.h>是用来设置边角的。

[plain] view
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#import "ViewController.h"

#import <QuartzCore/QuartzCore.h>

@interface ViewController ()

@end

@implementation ViewController

@synthesize myScrollView,pageControl;

-(void)initArray

{

imageArray=[NSArray arrayWithObjects: [UIImage imageNamed:@"share.png"],[UIImage imageNamed:@"home_baike.png"],[UIImage imageNamed:@"home_chat.png"],[UIImage imageNamed:@"Icon.png"],nil];

//存放图片的数组

}

- (void)viewDidLoad

{

[super viewDidLoad];

[self initArray];

[self configScrollView];

}

-(void)configScrollView

{

/*

@//初始化UIScrollView，设置相关属性，均可在storyBoard中设置

CGRect frame=CGRectMake(0, 0, 320, 480);

self.myScrollView = [[UIScrollView alloc]initWithFrame:frame]; //scrollView的大小

self.myScrollView.backgroundColor=[UIColor blueColor];

self.myScrollView.pagingEnabled=YES;//以页为单位滑动，即自动到下一页的开始边界

self.myScrollView.showsVerticalScrollIndicator=NO;

self.myScrollView.showsHorizontalScrollIndicator=NO;//隐藏垂直和水平显示条

*/

self.myScrollView.delegate=self;

UIImageView *firstView=[[UIImageView alloc] initWithImage:[imageArray lastObject]];

CGFloat Width=self.myScrollView.frame.size.width;

CGFloat Height=self.myScrollView.frame.size.height;

firstView.frame=CGRectMake(0, 0, Width, Height);

[self.myScrollView addSubview:firstView];

//set the last as the first

for (int i=0; i<[imageArray count]; i++) {

UIImageView *subViews=[[UIImageView alloc] initWithImage:[imageArray objectAtIndex:i]];

subViews.frame=CGRectMake(Width*(i+1), 0, Width, Height);

[self.myScrollView addSubview: subViews];

}

UIImageView *lastView=[[UIImageView alloc] initWithImage:[imageArray objectAtIndex:0]];

lastView.frame=CGRectMake(Width*(imageArray.count+1), 0, Width, Height);

[self.myScrollView addSubview:lastView];

//set the first as the last

[self.myScrollView setContentSize:CGSizeMake(Width*(imageArray.count+2), Height)];

[self.view addSubview:self.myScrollView];

[self.myScrollView scrollRectToVisible:CGRectMake(Width, 0, Width, Height) animated:NO];

//show the real first image,not the first in the scrollView

/*

@//设置pageControl的位置，及相关属性，可选

CGRect pageControlFrame=CGRectMake(100, 160, 78, 36);

self.pageControl=[[UIPageControl alloc]initWithFrame:pageControlFrame];

[self.pageControl setBounds:CGRectMake(0, 0, 16*(self.pageControl.numberOfPages-1), 16)];//设置pageControl中点的间距为16

[self.pageControl.layer setCornerRadius:8];//设置圆角

*/

self.pageControl.numberOfPages=imageArray.count;

// self.pageControl.backgroundColor=[UIColor blueColor];//背景

self.pageControl.currentPage=0;

self.pageControl.enabled=YES;

[self.view addSubview:self.pageControl];

[self.pageControl addTarget:self action:@selector(pageTurn:)forControlEvents:UIControlEventValueChanged];

myTimer=[NSTimer scheduledTimerWithTimeInterval:2.0f target:self selector:@selector(scrollToNextPage:) userInfo:nil repeats:YES];

}

#pragma UIScrollView delegate

-(void)scrollToNextPage:(id)sender

{

int pageNum=self.pageControl.currentPage;

CGSize viewSize=self.myScrollView.frame.size;

CGRect rect=CGRectMake((pageNum+2)*viewSize.width, 0, viewSize.width, viewSize.height);

[self.myScrollView scrollRectToVisible:rect animated:NO];

pageNum++;

if (pageNum==imageArray.count) {

CGRect newRect=CGRectMake(viewSize.width, 0, viewSize.width, viewSize.height);

[self.myScrollView scrollRectToVisible:newRect animated:NO];

}

}

-(void)scrollViewDidScroll:(UIScrollView *)scrollView

{

CGFloat pageWidth=self.myScrollView.frame.size.width;

int currentPage=floor((self.myScrollView.contentOffset.x-pageWidth/2)/pageWidth)+1;

if (currentPage==0) {

self.pageControl.currentPage=imageArray.count-1;

}else if(currentPage==imageArray.count+1){

self.pageControl.currentPage=0;

}

self.pageControl.currentPage=currentPage-1;

}

-(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView

{

[myTimer invalidate];

}

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

{

myTimer=[NSTimer scheduledTimerWithTimeInterval:2.0f target:self selector:@selector(scrollToNextPage:) userInfo:nil repeats:YES];

}

-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView

{

CGFloat pageWidth=self.myScrollView.frame.size.width;

CGFloat pageHeigth=self.myScrollView.frame.size.height;

int currentPage=floor((self.myScrollView.contentOffset.x-pageWidth/2)/pageWidth)+1;

NSLog(@"the current offset==%f",self.myScrollView.contentOffset.x);

NSLog(@"the current page==%d",currentPage);

if (currentPage==0) {

[self.myScrollView scrollRectToVisible:CGRectMake(pageWidth*imageArray.count, 0, pageWidth, pageHeigth) animated:NO];

self.pageControl.currentPage=imageArray.count-1;

NSLog(@"pageControl currentPage==%d",self.pageControl.currentPage);

NSLog(@"the last image");

return;

}else if(currentPage==[imageArray count]+1){

[self.myScrollView scrollRectToVisible:CGRectMake(pageWidth, 0, pageWidth, pageHeigth) animated:NO];

self.pageControl.currentPage=0;

NSLog(@"pageControl currentPage==%d",self.pageControl.currentPage);

NSLog(@"the first image");

return;

}

self.pageControl.currentPage=currentPage-1;

NSLog(@"pageControl currentPage==%d",self.pageControl.currentPage);

}

-(IBAction)pageTurn:(UIPageControl *)sender

{

int pageNum=pageControl.currentPage;

CGSize viewSize=self.myScrollView.frame.size;

[self.myScrollView setContentOffset:CGPointMake((pageNum+1)*viewSize.width, 0)];

NSLog(@"myscrollView.contentOffSet.x==%f",myScrollView.contentOffset.x);

NSLog(@"pageControl currentPage==%d",self.pageControl.currentPage); [myTimer invalidate];

}

@end

还存在的问题：当我点击UIPageControl中的白点时一次只能切换一张图片，即不能精确定位到某一个点所对应的图片，上网查了好多资料，都没有那个解决。貌似那样是不可以的，http://stackoverflow.com/questions/1103915/is-uipagecontrol-useless-by-itself和http://stackoverflow.com/questions/4037416/scrollview-pagecontrol-dot-doesnt-change-with-the-page?rq=1中有相关的讨论。希望各位牛人能帮忙解决一下这个问题。ps：stackoverflow.com是一个很牛气的网站，我的很多问题都是在这里找到解决办法的，这是一个英文网站，有时看着会比较吃力。努力学习英语啊，

，与各位同仁共勉。