UI06_无限滚动的相册

#import <UIKit/UIKit.h>

@interface AppDelegate : UIResponder <UIApplicationDelegate>

@property (strong, nonatomic) UIWindow *window;

@end

#import "AppDelegate.h"
#import "RootViewController.h"

@interface AppDelegate ()

@end

@implementation AppDelegate
- (void)dealloc
{
[_window release];
[super dealloc];
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];

[_window release];

RootViewController *rootVC = [[RootViewController alloc] init];
self.window.rootViewController = rootVC;
[rootVC release];

return YES;
}

#import <UIKit/UIKit.h>

@interface RootViewController : UIViewController

@end

#import "RootViewController.h"
#define WIDTH self.view.frame.size.width
#define HEIGHT self.view.frame.size.height

@interface RootViewController ()<UIScrollViewDelegate>
@property(nonatomic, retain)UIScrollView *scrollView;
@property(nonatomic, retain)UIPageControl *page;

@end

@implementation RootViewController
- (void)dealloc
{
[_scrollView release];
[super dealloc];
}
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.

self.view.backgroundColor = [UIColor whiteColor];

self.scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, WIDTH, HEIGHT)];
[self.view addSubview:self.scrollView];
[self.scrollView release];
self.scrollView.backgroundColor = [UIColor lightGrayColor];

self.scrollView.contentSize = CGSizeMake(9 * WIDTH, 0);
self.scrollView.pagingEnabled = YES;
self.scrollView.bounces = NO;
//  add the first image
UIImageView *firstImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, WIDTH, HEIGHT)];
firstImageView.image = [UIImage imageNamed:@"h7.jpeg"];
[self.scrollView addSubview:firstImageView];
[firstImageView release];
firstImageView.userInteractionEnabled = YES;

for (NSInteger i = 1; i < 8; i++) {
NSString *imageName = [NSString stringWithFormat:@"h%ld.jpeg", i];
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(i * WIDTH, 0, WIDTH, HEIGHT)];
imageView.image = [UIImage imageNamed:imageName];
[self.scrollView addSubview:imageView];
[imageView release];
imageView.userInteractionEnabled = YES;
}

//  add the last image  在最后面加上一个视图, 放在最后, 显示第一张图片
UIImageView *lastImageView = [[UIImageView alloc] initWithFrame:CGRectMake(8 * WIDTH, 0, WIDTH, HEIGHT)];
lastImageView.image = [UIImage imageNamed:@"h1.jpeg"];
[self.scrollView addSubview:lastImageView];
[lastImageView release];
lastImageView.userInteractionEnabled = YES;
//  为了能显示第一张图片, 我们需要先设置一个偏移量, 这样能直接显示罗宾的第一张图片
self.scrollView.contentOffset = CGPointMake(WIDTH, 0);

//  设置代理人
self.scrollView.delegate = self;

//  用定时器实现无限滚动
//    [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(changeImage) userInfo:nil repeats:YES];

//  创建一个pageControl
self.page = [[UIPageControl alloc] initWithFrame:CGRectMake(100, 100, 150, 30)];
[self.view addSubview:self.page];
[self.page release];
self.page.backgroundColor = [UIColor cyanColor];
self.page.numberOfPages = 7;
//  设置未被点的颜色
self.page.pageIndicatorTintColor = [UIColor blackColor];
//  选中的点的颜色
self.page.currentPageIndicatorTintColor = [UIColor whiteColor];

//  touchupInside 和 valueChange 皆可用+
[self.page addTarget:self action:@selector(changePage:) forControlEvents:UIControlEventValueChanged];

//  想要scrollView实现缩放功能, 需要先设置最大最小缩放比例
self.scrollView.minimumZoomScale = 0.5;
self.scrollView.maximumZoomScale = 2;

}
#pragma mark    这个方法用来管理scrollView的缩放功能
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
NSLog(@"fsaf");
return [scrollView.subviews firstObject];
}

- (void)changePage:(UIPageControl *)page {
//  还是设置偏移量
//    self.scrollView.contentOffset = CGPointMake(page.currentPage * WIDTH + WIDTH, 0);
NSLog(@"%ld", page.currentPage);
[self.scrollView setContentOffset:CGPointMake(page.currentPage * WIDTH + WIDTH, 0) animated:YES];
}

- (void)changeImage {
[self.scrollView setContentOffset:CGPointMake(self.scrollView.contentOffset.x - WIDTH, 0) animated:YES];
//  自动向右滚动,,,需在上式改为+WIDTH
//    if (self.scrollView.contentOffset.x == 8 * WIDTH) {
//        self.scrollView.contentOffset = CGPointMake(WIDTH, 0);
//    }
//  自动向左滚动
if (self.scrollView.contentOffset.x == 0) {
self.scrollView.contentOffset = CGPointMake(WIDTH * 7, 0);
}
}

//  滑动结束, 触发的协议方法
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
if (self.scrollView.contentOffset.x == 8 * WIDTH) {
self.scrollView.contentOffset = CGPointMake(WIDTH, 0);
}
if (self.scrollView.contentOffset.x == 0) {
self.scrollView.contentOffset = CGPointMake(7 * WIDTH, 0);
}

//  pageControl和scrollView进行关联, 点的移动方向和scrollView的偏移量相关
//  无论怎么方向滑动, 当pageControl和scrollView关联的时候, 偏移量都是修改好的, 所以可以正确的滚动和显示
self.page.currentPage = self.scrollView.contentOffset.x / WIDTH - 1;

}