• UIScrollView与UIPageController结合使用实现轮播


      1 #import "ViewController.h"
      2 #define WIDTH self.view.frame.size.width
      3 #define HEIGHT self.view.frame.size.height
      4 @interface ViewController ()<UIScrollViewDelegate>
      5 @property (strong,nonatomic) UIImageView *imageView;
      6 @property (strong,nonatomic) UIScrollView *scroll;
      7 @property (strong,nonatomic) UIPageControl *pageControl;
      8 @end
      9 
     10 @implementation ViewController
     11 
     12 - (void)viewDidLoad {
     13     [super viewDidLoad];
     14     self.view.backgroundColor = [UIColor grayColor];
     15     //创建一个和屏幕等尺寸的ScorllView
     16     _scroll = [[UIScrollView alloc] initWithFrame:self.view.frame];
     17     _scroll.backgroundColor = [UIColor yellowColor];
     18     //重要:水平方向滚动位置,contentSize--滚动范围
     19     _scroll.contentSize = CGSizeMake(WIDTH * 7, 0);
     20     
     21     //重要---按页来滚动
     22     _scroll.pagingEnabled = YES;
     23     //关闭屏幕回弹效果
     24     _scroll.bounces = NO;
     25     //关闭滚动条
     26     _scroll.showsHorizontalScrollIndicator = NO;
     27     //非常重要-偏移量
     28 #pragma ************如果下边这一句不注掉那么运行工程的时候系统会自动偏移一次,从而会显示第二张图片
     29     //_scroll.contentOffset = CGPointMake(WIDTH, 0);
     30     //垂直方向的滚动范围
     31     _scroll.contentSize = CGSizeMake(WIDTH * 7, 0);
     32     _scroll.maximumZoomScale = 2;
     33     _scroll.minimumZoomScale = 0.5;
     34 
     35     //水平方向的视图摆放
     36     for (int i = 1; i < 8; i++) {
     37         //创建小的scrollView
     38         UIScrollView *scroll2 = [[UIScrollView alloc]initWithFrame:CGRectMake((i - 1) * WIDTH, 0, WIDTH, HEIGHT)];
     39        
     40         //循环创建视图,添加到srollView上
     41         self.imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, WIDTH, HEIGHT)];
     42         self.imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"h%d.jpeg",i]];
     43         [scroll2 addSubview:self.imageView];
     44         //一定要记得为每个小的scroll添加代理,否则不能实现缩放
     45         scroll2.delegate = self;
     46         scroll2.maximumZoomScale = 2;
     47         scroll2.minimumZoomScale = 0.5;
     48          [_scroll addSubview:scroll2];
     49     }
     50 //        //垂直方向的偏移量
     51 //    _scroll.contentOffset = CGPointMake(0, HEIGHT);
     52 //    for (int i = 1; i < 8; i++) {
     53 //        UIScrollView *scroll2 = [[UIScrollView alloc] initWithFrame:CGRectMake(0, (i - 1) * HEIGHT, WIDTH, HEIGHT)];
     54 //        [_scroll addSubview:scroll2];
     55 //        //self.imageView.frame = self.view.frame;
     56 //        self.imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, WIDTH, HEIGHT)];
     57 //        self.imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"h%d.jpeg",i]];
     58 //        [scroll2 addSubview:self.imageView];
     59 //    }
     60     
     61 //    self.scroll.maximumZoomScale = 2;
     62 //    self.scroll.minimumZoomScale = 0.5;
     63     
     64     [self.view addSubview:_scroll];
     65     _scroll.delegate = self;
     66     //添加手势,双击屏幕,缩放回到原型
     67     UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(setScrollZoom)];
     68     tap.numberOfTapsRequired =2;
     69     [self.scroll addGestureRecognizer:tap];
     70     
     71     
     72     _pageControl = [[UIPageControl alloc] initWithFrame:CGRectMake(0, HEIGHT - 80, WIDTH, 40)];
     73     _pageControl.numberOfPages = 7;
     74     _pageControl.pageIndicatorTintColor = [UIColor redColor];
     75     //当前页指示器(也就是小点点)的颜色
     76     _pageControl.currentPageIndicatorTintColor = [UIColor greenColor];
     77     [self.view addSubview:_pageControl];
     78     [_pageControl addTarget:self action:@selector(pagAction:) forControlEvents:UIControlEventValueChanged];
     79   
     80    
     81 }
     82 //实现代理里的缩放
     83 -(UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
     84 {
     85     _scroll.subviews[0].center = self.view.center;
     86     return scrollView.subviews[0];
     87 }
     88 #pragma mark - page的响应事件
     89 
     90 - (void)pagAction:(UIPageControl *)sender{
     91     //根据paged当前的小圆点算出现在在显示的是第几张图片,从而改变偏移量   setContentOffset(跳转至指定的页面)
     92     [self.scroll setContentOffset:CGPointMake(self.pageControl.currentPage * WIDTH, 0) animated:YES];
     93     [self setScrollZoom];
     94 }
     95 #pragma mark - 把所有的小scrollView的缩放比例变为1,也就是改回原型
     96 - (void)setScrollZoom{
     97     //当减速结束的时候,那张图回复原样
     98     //把所有的imv的缩放比例设置为1
     99     for (UIScrollView *s in self.scroll.subviews) {
    100         if ([s isKindOfClass:[UIScrollView class]]) {
    101             [s setZoomScale:1 animated:NO];
    102         }
    103     }
    104 }
    105 
    106 
    107 
    108 
    109 
    110 -(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
    111 {
    112     NSLog(@"开始拖拽的时候触发");
    113 }
    114 #pragma mark--UIScrollView 滚动协议方法
    115 -(void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
    116 {
    117     [self setScrollZoom];
    118     NSLog(@"结束拖拽时触发");
    119 }
    120 
    121 
    122 
    123 -(void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView
    124 {
    125     NSLog(@"开始减速时触发");
    126 }
    127 #pragma mark -scroll的代理方法,减速结束
    128 -(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
    129 {
    130     //根据偏移量算出现在在显示的是第几张图片,从而改变paged当前的小圆点
    131     self.pageControl.currentPage = self.scroll.contentOffset.x/WIDTH;
    132     [self setScrollZoom];
    133     NSLog(@"减速完成时触发");
    134 }
    135 
    136 - (void)didReceiveMemoryWarning {
    137     [super didReceiveMemoryWarning];
    138     // Dispose of any resources that can be recreated.
    139 }
    140 
    141 @end
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  • 原文地址:https://www.cnblogs.com/DevinSMR/p/5170159.html
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