collectionViewFlow的界面编写

#import <UIKit/UIKit.h>

//这边我们会创建一个scrollView的界面，这个scrollView里面有三张图片构成，我们使用下面的枚举方式来定义这三个位置
typedef NS_ENUM(NSInteger, MRImgLocation) {
    MRImgLocationLeft,
    MRImgLocationCenter,
    MRImgLocationRight,
};


@interface MRimgView : UIScrollView <UIScrollViewDelegate>
{
    NSDictionary* _imgViewDic;   // 这个字典里面存放了scrollView的图片，一共三个图片
}

@property(nonatomic ,retain)NSMutableArray *imgSource;
@property(nonatomic ,assign)NSInteger curIndex;     // 当前显示图片在数据源中的下标

- (id)initWithFrame:(CGRect)frame withSourceData:(NSMutableArray *)imgSource withIndex:(NSInteger)index;

// 谦让双击放大手势
- (void)requireDoubleGestureRecognizer:(UITapGestureRecognizer *)tep;

@end

这边通过一个实际例子来介绍collectionViewFlow。下面是完成这个collectionViewFlow的文件：

介绍这些文件的作用：

首先第一个collectionView文件，在此文件中创建一个collectionViewFlow的瀑布流图片。

然后第二个imgViewController文件，在此文件中创建一个viewController界面，和普通的viewController界面没有什么区别。

最后第三个MRimgView文件，在此文件中创建一个scrollView界面，我们在这里可以图片的放大操作和滑动观看操作。

以上文件的链接过程：首先我们点击进入瀑布流图片界面（collectionView文件），然后我们点击一个图片的滚动视图界面（在imgViewController文件的界面上添加了一个MRimgView的滚动视图界面），就这样完成了瀑布流图片的界面。

下面来对这些文件进行一一介绍：

首先我们来介绍collectionView文件：

//＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊collectionView.h＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊//

#import <UIKit/UIKit.h>

@interface collectionView : UIViewController<UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout>
//这里我们遵循了三个协议，这三个协议分别是collection的数据源，委托和自动布局协议

@property (nonatomic, strong) NSMutableArray *DataImage;//储存图片信息

@end

//＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊collectionView.m＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊//

#import "collectionView.h"
#import "imgViewController.h"

//我们要在这个界面上调用这个文件，在navigation中push一个imgviewController文件

@interface collectionView ()
{
    NSString *_identify;
//    用于创建collectionView的cell
}

@end

@implementation collectionView

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    self.title = @"图片列表";
    [self _requestData];
    [self _init];
    self.navigationController.navigationBarHidden = YES;
}

-(void) _requestData
{
    //     请求数据，储存图片
    self.DataImage = [[NSMutableArray alloc] init];
    
    for (int i = 0; i < 12; i++) {
        NSString *imgName = [NSString stringWithFormat:@"%d.jpg",i];
        UIImage *img = [UIImage imageNamed:imgName];
        [self.DataImage addObject:img];
    }
}

-(void) _init
{
    //    首先我们创建布局对象
    UICollectionViewFlowLayout *viewLayout = [[UICollectionViewFlowLayout alloc] init];
    viewLayout.itemSize = CGSizeMake(100, 150);
    viewLayout.minimumLineSpacing = 6;//设置每行之间的最小间距
    viewLayout.minimumInteritemSpacing = 6;//设置每行中的图片的最小间距
    
    //    设置我们的集合视图流
    UICollectionView *collectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(3, 3, self.view.frame.size.width - 6, self.view.frame.size.height - 80) collectionViewLayout:viewLayout];
    collectionView.dataSource = self;
    collectionView.delegate = self;
    collectionView.backgroundColor = [UIColor clearColor];
    
    //为该cellectionView实例注册单元格
    _identify = @"PhotoCell";
    [collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:_identify];
    
//    将刚刚创建的collectionView添加到界面上
    [self.view addSubview:collectionView];
    
//    添加navigationBar的左箭头
    //    自定义按钮barLeft
    UIButton *actionBtnlf = [UIButton buttonWithType:UIButtonTypeCustom];
    [actionBtnlf setTitle:@"" forState:UIControlStateNormal];
    UIImage *imgDefault = [UIImage imageNamed:@"Arrow"];
    [actionBtnlf setFrame:CGRectMake(0, 0, imgDefault.size.width, imgDefault.size.height)];
    [actionBtnlf setBackgroundImage:imgDefault forState:UIControlStateNormal];
    [actionBtnlf addTarget:self action:@selector(backButtonAction) forControlEvents:UIControlEventTouchUpInside];
    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:actionBtnlf];
}

//下面实现我们collectionView里面的delegate和datasource里面的方法
-(NSInteger) collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
    //    返回每一个section里面的试图的数量，这边我们就只有一个section
    return self.DataImage.count;
}

-(UICollectionViewCell *) collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
    //    创建我们的cell，并且返回cell到的集合试图的相应位置
    UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:_identify forIndexPath:indexPath];
    cell.backgroundColor = [UIColor clearColor];
    UIImage *image = self.DataImage[indexPath.row];
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
    imageView.contentMode = UIViewContentModeScaleToFill;
    
    imageView.frame = CGRectMake(0, 0, 100, 150);
    
    [cell.contentView addSubview:imageView];
    
    return cell;
}

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
    //    点击相应的视图的时候，我们将调用这个方法
    // 深拷贝数据
    NSMutableArray *imgList = [NSMutableArray arrayWithCapacity:self.DataImage.count];
    for (int i = 0; i < self.DataImage.count; i++) {
        UIImage *imgMod = self.DataImage[i];
        [imgList addObject:imgMod];
    }
    // 调用展示窗口，这边调用的这个方法是imgViewController借口文件中的方法
    imgViewController *imgView = [[imgViewController alloc] initWithSourceData:imgList withIndex:indexPath.row];
    [self.navigationController pushViewController:imgView animated:YES];
}

#pragma mark -View生命周期
- (void)viewWillAppear:(BOOL)animated{
//    每当这个视图出现的时候，这个函数都会被调用
    if (self.navigationController.navigationBar.translucent) {
        self.navigationController.navigationBar.translucent = NO;
    }
    if (self.navigationController.navigationBarHidden) {
        self.navigationController.navigationBarHidden = NO;
    }
}

-(void) backButtonAction
{
    [self.navigationController popViewControllerAnimated:YES];
    self.navigationController.navigationBarHidden = YES;
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

下面是imgViewController文件

//＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊imgcollectionView.h＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊//

#import <UIKit/UIKit.h>

@interface imgViewController : UIViewController

@property (strong, nonatomic) NSMutableArray *data;//储存数据
@property (nonatomic, assign) NSInteger index;//储存点击的图片的位置

- (id)initWithSourceData:(NSMutableArray *)data withIndex:(NSInteger)index;

@end

//＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊imgcollectionView.m＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊//

#import "imgViewController.h"
#import "MRimgView.h"
//我们在这里要加载一个MRimgview中的scrollView的文件

@interface imgViewController ()

@end

@implementation imgViewController
- (id)initWithSourceData:(NSMutableArray *)data withIndex:(NSInteger)index{
    
    self = [super init];
    if (self) {
        _data = data;
        _index = index;
    }
    return self;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
    
    self.title = @"图片列表";
    //设置导航栏为半透明
    self.navigationController.navigationBar.translucent = YES;
    // 隐藏标签栏
    self.tabBarController.tabBar.hidden = YES;
    // 隐藏导航栏
    self.navigationController.navigationBarHidden = YES;
    
//    这里我们创建一个手势，点击View一下，此事件触发
    UITapGestureRecognizer *tapGestureOne = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapGestureOneAction)];
    tapGestureOne.numberOfTapsRequired = 1;
    [self.view addGestureRecognizer:tapGestureOne];
    
    self.automaticallyAdjustsScrollViewInsets = NO;
    [self.view setBackgroundColor:[UIColor blackColor]];
    
    //    添加navigationBar的左箭头
    //    自定义按钮barLeft
    UIButton *actionBtnlf = [UIButton buttonWithType:UIButtonTypeCustom];
    [actionBtnlf setTitle:@"" forState:UIControlStateNormal];
    UIImage *imgDefault = [UIImage imageNamed:@"Arrow"];
    [actionBtnlf setFrame:CGRectMake(0, 0, imgDefault.size.width, imgDefault.size.height)];
    [actionBtnlf setBackgroundImage:imgDefault forState:UIControlStateNormal];
    [actionBtnlf addTarget:self action:@selector(backButtonAction) forControlEvents:UIControlEventTouchUpInside];
    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:actionBtnlf];
    //    为这个视图添加图片
    [self creatImgShow];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

-(void) creatImgShow
{
    //    为视图添加图片
    MRimgView *imgShowView = [[MRimgView alloc]
                              initWithFrame:self.view.frame
                              withSourceData:_data
                              withIndex:_index];
//谦让双击方法事件
    [imgShowView requireDoubleGestureRecognizer:[[self.view gestureRecognizers] lastObject]];
    
    [self.view addSubview:imgShowView];
}
-(void) tapGestureOneAction
{
    //    点按视图一下，启动的action,隐藏导航栏或者出现导航栏
    [UIView animateWithDuration:0.3 animations:^{
        self.navigationController.navigationBarHidden = !self.navigationController.navigationBarHidden;
    }];
}

-(void) backButtonAction
{
    [self.navigationController popViewControllerAnimated:YES];
}
/*
 #pragma mark - Navigation
 
 // In a storyboard-based application, you will often want to do a little preparation before navigation
 - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
 // Get the new view controller using [segue destinationViewController].
 // Pass the selected object to the new view controller.
 }
 */

@end

//＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊MRimgView.h＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊//

#import <UIKit/UIKit.h>

//这边我们会创建一个scrollView的界面，这个scrollView里面有三张图片构成，我们使用下面的枚举方式来定义这三个位置
typedef NS_ENUM(NSInteger, MRImgLocation) {
    MRImgLocationLeft,
    MRImgLocationCenter,
    MRImgLocationRight,
};


@interface MRimgView : UIScrollView <UIScrollViewDelegate>
{
    NSDictionary* _imgViewDic;   // 这个字典里面存放了scrollView的图片，一共三个图片
}

@property(nonatomic ,retain)NSMutableArray *imgSource;
@property(nonatomic ,assign)NSInteger curIndex;     // 当前显示图片在数据源中的下标

- (id)initWithFrame:(CGRect)frame withSourceData:(NSMutableArray *)imgSource withIndex:(NSInteger)index;

// 谦让双击放大手势
- (void)requireDoubleGestureRecognizer:(UITapGestureRecognizer *)tep;

@end

//＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊MRimgView.m＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊//

#import "MRimgView.h"

#define kImgViewCount 3
#define kImgZoomScaleMin 1
#define kImgZoomScaleMax 3

@implementation MRimgView
{
    UIScrollView *_scrCenter;
}

- (id)initWithFrame:(CGRect)frame withSourceData:(NSMutableArray *)imgSource withIndex:(NSInteger)index
{
    //    将我们的image传入这个类，然后将图片位置传入类中，还有这个图片的大小
    self = [super initWithFrame:frame];
    
    if (self) {
        //        初始化空间属性
        [self initScroller];
        
        //        设置数据源的操作
        [self setImgSource:imgSource];
        
        //        设置图片下标
        [self setCurIndex:index];
    }
    return self;
}

-(void) initScroller
{
    //    初始化self的scrollerView控件属性
    self.delegate = self;
    self.showsHorizontalScrollIndicator = NO;
    self.showsVerticalScrollIndicator = NO;
    self.pagingEnabled = YES;
    self.backgroundColor = [UIColor clearColor];
    
    // 构建展示组
    [self initImgViewDic];
}

- (void)setImgSource:(NSMutableArray *)imgSource
{
    //    这边我们进行数据的插入操作
    if (_imgSource != imgSource) {
        _imgSource = imgSource;
        
        //  设置展示板尺寸
        [self setConSize];
    }
    
}

// 展示板尺寸设置
- (void)setConSize{
    
    CGSize size = self.frame.size;
    
    //设置内容视图的大小--单页填充、横向划动
    self.contentSize = CGSizeMake(size.width * kImgViewCount, size.height);
    
    // 设置显示页 这句话的作用是设置了滚动视图现实在屏幕上的区域，距离坐标原点的向量是（320，0），因此把scrCenter显示在屏幕上
    [self setContentOffset:CGPointMake(size.width, 0)];
}

// 初始化展示板组
-(void) initImgViewDic
{
    UIImageView *imgLeft = [self creatImageView];
    UIImageView *imgCenter = [self creatImageView];
    UIImageView *imgRight = [self creatImageView];
    
    _imgViewDic = [[NSDictionary alloc] initWithObjectsAndKeys:
                   imgLeft, @"imgLeft",
                   imgCenter, @"imgCenter",
                   imgRight, @"imgRight",
                   nil];
    
    //    创建滚动视图
    UIScrollView *scrLeft =
    [self scrollViewWithPosition:MRImgLocationLeft withImgView:imgLeft];
    _scrCenter =
    [self scrollViewWithPosition:MRImgLocationCenter withImgView:imgCenter];
    UIScrollView *scrRight =
    [self scrollViewWithPosition:MRImgLocationRight withImgView:imgRight];
    
    //设置放大缩小极限倍数
    _scrCenter.maximumZoomScale = kImgZoomScaleMax;
    _scrCenter.minimumZoomScale = kImgZoomScaleMin;
    
    _scrCenter.delegate = self;
    
    // 添加双击手势
    UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doubleTapClick:)];
    doubleTap.numberOfTapsRequired = 2;
    
    [self addGestureRecognizer:doubleTap];
    
    // 放入展示板
    [self addSubview:scrLeft];
    [self addSubview:_scrCenter];
    [self addSubview:scrRight];
}

// 通过创建展示板
- (UIImageView *)creatImageView{
    
    CGFloat width = self.frame.size.width;
    CGFloat height = self.frame.size.height;
    
    UIImageView *imgView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, width, height)];
    
    return imgView;
}

- (UIScrollView *)scrollViewWithPosition:(MRImgLocation)imgLocation withImgView:(UIImageView *)imgView
{
    //    创建滚动视图
    CGFloat width = self.frame.size.width;
    CGFloat height= self.frame.size.height;
    
    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(width * imgLocation, 0, width, height)];
    scrollView.backgroundColor = [UIColor blackColor];
    
    [scrollView addSubview:imgView];
    
    // 设置图片显示样式
    imgView.contentMode = UIViewContentModeScaleAspectFit;
    
    return scrollView;
}

- (void)setCurIndex:(NSInteger)curIndex
{
    //    设置图片内容
    //第2、3个if是为了设置循环滚动
    if (_imgSource.count > curIndex && curIndex >= 0) {
        _curIndex = curIndex;
    } else if (curIndex == -1){
        _curIndex = _imgSource.count - 1;
    } else if (curIndex == _imgSource.count){
        _curIndex = 0;
    }
    
    if (_imgSource.count)
    {[self setAllImgVContentFromImage:[self imgListFromIndex:_curIndex]];}
}

// 载入一组图片
- (void)setAllImgVContentFromImage:(NSArray *)imgList{
    
    // 将所有imgList中的数据载入展示板
    UIImageView *vLift = [_imgViewDic valueForKey:@"imgLeft"];
    UIImageView *vCenter = [_imgViewDic valueForKey:@"imgCenter"];
    UIImageView *vRight = [_imgViewDic valueForKey:@"imgRight"];
    
    [vLift setImage:imgList[MRImgLocationLeft]];
    [vCenter setImage:imgList[MRImgLocationCenter]];
    [vRight setImage:imgList[MRImgLocationRight]];
}

// 根据当前索引赋值图片   该方法返回一个存有左中右3个image的数组
- (NSArray *)imgListFromIndex:(NSInteger)curIndex{
    
    long sCount = _imgSource.count;
    NSArray *imgList;
    
    UIImage *imgL;
    UIImage *imgC;
    UIImage *imgR;
    
    if (sCount) {
        
        // 首位
        if (curIndex == 0) {
            imgL = [_imgSource lastObject];
            imgC = _imgSource[curIndex];
            long nextIndex = curIndex == sCount - 1 ? curIndex : curIndex + 1;
            imgR = _imgSource[nextIndex];
            // 末位
        } else if (curIndex == sCount - 1){
            long lastIndex = curIndex == 0 ? curIndex : curIndex - 1;
            imgL = _imgSource[lastIndex] ;
            imgC = [_imgSource lastObject];
            imgR = _imgSource[0];
            // 中间
        } else {
            imgL = _imgSource[curIndex - 1];
            imgC = _imgSource[curIndex];
            imgR = _imgSource[curIndex + 1];
        }
        
        imgList = [[NSArray alloc] initWithObjects:imgL, imgC, imgR, nil];
    }
    
    return imgList;
}

- (void)doubleTapClick:(UITapGestureRecognizer *)tap
{
    //    在这里实现点按两下的action操作
    //    判断当前放大的比例
    if (_scrCenter.zoomScale > kImgZoomScaleMin) {
        [_scrCenter setZoomScale:kImgZoomScaleMin animated:YES];
    }
    else
        [_scrCenter setZoomScale:kImgZoomScaleMax animated:YES];
}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{
    UIImageView *vCenter = [_imgViewDic valueForKey:@"imgCenter"];
    return vCenter;
}

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
    if (self == scrollView) {
        CGFloat width = self.frame.size.width;
        int currentOffset = scrollView.contentOffset.x/width - 1;
        [self setCurIndex:_curIndex + currentOffset];
        
        //        返回三个视图中的中间位置
        [scrollView setContentOffset:CGPointMake(width, 0) animated:NO];
        [_scrCenter setZoomScale:kImgZoomScaleMin];
    }
}

// 谦让双击放大手势
- (void)requireDoubleGestureRecognizer:(UITapGestureRecognizer *)tep{
    [tep requireGestureRecognizerToFail:[[self gestureRecognizers] lastObject]];
}
/*
 // Only override drawRect: if you perform custom drawing.
 // An empty implementation adversely affects performance during animation.
 - (void)drawRect:(CGRect)rect {
 // Drawing code
 }
 */

@end

这样，我们就完成了我们瀑布流图片编写。