UI-UIScrollView

UIScrollView控制内容显⽰
contentSize //定义内容区域⼤大⼩小,决定是否能够滑动 contentOffset //内容左上⾓角距离坐标原点的偏移量 contentInset//内容区域相对frame上下左右从哪⼉儿显⽰示

UIScrollView管理滚动
scrollEnabled //判断控件是否能够滚动 directionalLockEnabled//限定滚动⽅方向 showsHorizontalScrollIndicator//控制是否显⽰示⽔水平⽅方向的滚动 showVerticalScrollIndicator //控制是否显⽰示垂直⽅方向的滚动条 scrollsToTop //滑动到顶部(点状态条的时候) pagingEnabled//是否整屏翻动 bounces//边界是否回弹


- (void)scrollRectToVisible:(CGRect)rect animated:(BOOL)animated;        // scroll so rect is just visible (nearest edges). nothing if rect completely visible

设置可视化区域

滚动相册的部分代码

#import "RootViewController.h"

#define KCount 8 // 图片个数
#define kWidth self.view.bounds.size.width // 根视图的宽度
#define kHeight self.view.bounds.size.height // 根视图的高度

@interface RootViewController () <UIScrollViewDelegate>

@property (nonatomic, strong) UIScrollView *scrollView;
@property (nonatomic, strong) UIPageControl *pageControl;
@property (nonatomic, strong) NSMutableArray *array; // 数组来放image

@end

@implementation RootViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
//    // 定时器循环
    [NSTimer scheduledTimerWithTimeInterval:3 target:self selector:@selector(runTimePage) userInfo:nil repeats:YES];
#pragma mark - scrollView的定制
    _scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
    [self.view addSubview:_scrollView];
   
    // 取消显示水平滑动条
    _scrollView.showsHorizontalScrollIndicator = NO;
    // 设置分页效果
    _scrollView.pagingEnabled = YES;
    // 开启用户视图交互
    _scrollView.userInteractionEnabled = YES;
    // 设置scrollView的代理
    _scrollView.delegate = self;
#pragma mark - 设置图片
    _array = [NSMutableArray arrayWithCapacity:1];
    for (int i = 0; i < KCount; i++) {
        NSString *imageName = [NSString stringWithFormat:@"0%d.jpg",i+1];
        UIImage *image = [UIImage imageNamed:imageName];
        [_array addObject:image];
        UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
        imageView.frame = CGRectMake((i+1) * kWidth, 0, kWidth, kHeight);
        [_scrollView addSubview:imageView];
    }
    // 取出最后一张图片放第一张
    UIImageView *ImageView = [[UIImageView alloc] initWithImage:[_array lastObject]];
    ImageView.frame = CGRectMake(0, 0, kWidth, kHeight);
    [_scrollView addSubview:ImageView];
    // 取出最后一张放到第一张
    ImageView = [[UIImageView alloc] initWithImage:[_array firstObject]];
    ImageView.frame = CGRectMake((KCount+1) * kWidth, 0, kWidth, kHeight);
    [_scrollView addSubview:ImageView];
    // 设置scrollView的可视范围
    _scrollView.contentSize = CGSizeMake((KCount+2) * kWidth, kHeight);
    // scrollView显示到  设置可视范围内的区域
    [_scrollView scrollRectToVisible:CGRectMake(kWidth, 0, kWidth, kHeight) animated:NO];
#pragma mark - PageControl的设置
    _pageControl = [[UIPageControl alloc] init];
    // 设置中点
    _pageControl.center = CGPointMake(kWidth / 2, kHeight - 20);
    // 设置页数
    _pageControl.numberOfPages = KCount;
    // 没被选中原点的颜色
    _pageControl.pageIndicatorTintColor = [UIColor blackColor];
    // 被选中原点的颜色
    _pageControl.currentPageIndicatorTintColor = [UIColor yellowColor];
    // 绑定pageControl方法
    [_pageControl addTarget:self action:@selector(turnPage) forControlEvents:UIControlEventValueChanged];
    [self.view addSubview:_pageControl];
}
#pragma mark - scrollView拖动时调用
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
//    int page = floor((self.scrollView.contentOffset.x - kWidth/(KCount+2))/kWidth); // 向下取整
    int page = (int)(self.scrollView.contentOffset.x/320) - 1;
    _pageControl.currentPage = page;
}
#pragma mark - scrollview滚动减速结束时调用
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
//    int currentPage = floor((self.scrollView.contentOffset.x - kWidth/(KCount+2))/kWidth) + 1; // 得到屏幕显示图片的页数
   
    int currentPage = (int)self.scrollView.contentOffset.x/320; // 和上面两行效果一样
    if (currentPage==0)
    {
        [self.scrollView scrollRectToVisible:CGRectMake(kWidth * KCount,0,kWidth,kHeight) animated:NO]; // 序号0 最后1页
    }
    else if (currentPage == (KCount+1))
    {
        [self.scrollView scrollRectToVisible:CGRectMake(kWidth,0,kWidth,kHeight) animated:NO]; // 最后+1,循环第1页
    }
}
#pragma mark - 实现定时器绑定方法
- (void)runTimePage
{
    int page = _pageControl.currentPage; // 获取当前的图片
    page++;
    page = page > KCount-1 ? 0 : page; // 页数循环
    _pageControl.currentPage = page;
    [self turnPage];
}
#pragma mark - pageControl绑定的方法
- (void)turnPage
{
    int page = _pageControl.currentPage; // 获取当前页数
    [_scrollView scrollRectToVisible:CGRectMake((page + 1) * kWidth, 0, kWidth, kHeight) animated:NO];
}