ios开发瀑布流框架的应用

一：瀑布流框架的应用：将封装好的瀑布流框架导入，遵守协议

二：代码：

 #import "HMShopsViewController.h"
 #import "HMShopCell.h"
 #import "HMWaterflowView.h"
 #import "HMShop.h"
 #import "MJExtension.h"
 #import "MJRefresh.h"

 @interface HMShopsViewController ()<HMWaterflowViewDataSource, HMWaterflowViewDelegate>
 @property (nonatomic, strong) NSMutableArray *shops;
 @property (nonatomic, weak) HMWaterflowView *waterflowView;
 @end

 @implementation HMShopsViewController

 - (NSMutableArray *)shops
 {
     if (_shops == nil) {
         self.shops = [NSMutableArray array];
     }
     return _shops;
 }

 - (void)viewDidLoad
 {
     [super viewDidLoad];

     // 0.初始化数据
     NSArray *newShops = [HMShop objectArrayWithFilename:@"2.plist"];
     [self.shops addObjectsFromArray:newShops];

     // 1.瀑布流控件
     HMWaterflowView *waterflowView = [[HMWaterflowView alloc] init];
     waterflowView.backgroundColor = [UIColor redColor];
     // 跟随着父控件的尺寸而自动伸缩
     waterflowView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
     waterflowView.frame = self.view.bounds;
     waterflowView.dataSource = self;
     waterflowView.delegate = self;
     [self.view addSubview:waterflowView];
     self.waterflowView = waterflowView;

     // 2.继承刷新控件
 //    [waterflowView addFooterWithCallback:^{
 //        NSLog(@"进入上拉加载状态");
 //    }];

 //    [waterflowView addHeaderWithCallback:^{
 //        NSLog(@"进入下拉加载状态");
     //    }];

     [waterflowView addHeaderWithTarget:self action:@selector(loadNewShops)];
     [waterflowView addFooterWithTarget:self action:@selector(loadMoreShops)];
 }

 - (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
 {
 //    NSLog(@"屏幕旋转完毕");
     [self.waterflowView reloadData];
 }

 - (void)loadNewShops
 {
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
         // 加载1.plist
         NSArray *newShops = [HMShop objectArrayWithFilename:@"1.plist"];
         [self.shops insertObjects:newShops atIndexes:[NSIndexSet indexSetWithIndexesInRange:NSMakeRange(, newShops.count)]];
     });

     dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
         // 刷新瀑布流控件
         [self.waterflowView reloadData];

         // 停止刷新
         [self.waterflowView headerEndRefreshing];
     });
 }

 - (void)loadMoreShops
 {
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
         // 加载3.plist
         NSArray *newShops = [HMShop objectArrayWithFilename:@"3.plist"];
         [self.shops addObjectsFromArray:newShops];
     });

     dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{

         // 刷新瀑布流控件
         [self.waterflowView reloadData];

         // 停止刷新
         [self.waterflowView footerEndRefreshing];
     });
 }

 #pragma mark - 数据源方法
 - (NSUInteger)numberOfCellsInWaterflowView:(HMWaterflowView *)waterflowView
 {
     return self.shops.count;
 }

 - (HMWaterflowViewCell *)waterflowView:(HMWaterflowView *)waterflowView cellAtIndex:(NSUInteger)index
 {
     HMShopCell *cell = [HMShopCell cellWithWaterflowView:waterflowView];

     cell.shop = self.shops[index];

     return cell;
 }

 - (NSUInteger)numberOfColumnsInWaterflowView:(HMWaterflowView *)waterflowView
 {
     if (UIInterfaceOrientationIsPortrait(self.interfaceOrientation)) {
         // 竖屏
         return ;
     } else {
         return ;
     }
 }

 #pragma mark - 代理方法
 - (CGFloat)waterflowView:(HMWaterflowView *)waterflowView heightAtIndex:(NSUInteger)index
 {
     HMShop *shop = self.shops[index];
     // 根据cell的宽度 和 图片的宽高比 算出 cell的高度
     return waterflowView.cellWidth * shop.h / shop.w;
 }
 @end

知识点分析：1:利用MJEXtension将plist文件转化成模型数组：NSArray *newShops = [HMShop objectArrayWithFilename:@"2.plist"]; [self.shops addObjectsFromArray:newShops];2：向数据源中添加数据：addObjectsFromArray , insertObject atIndexes :NSArray *newShops = [HMShop objectArrayWithFilename:@"1.plist"]; [self.shops insertObjects:newShops atIndexes:[NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, newShops.count)]];

2:监听屏幕的旋转：在控制器中实现didRotateFromInterfaceOrientation，可以实现对屏幕旋转的监听，此时设置waterFlow的autoresizingMask属性，设置其宽高随父视图宽高自由伸缩，waterflowView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;在返回列数的代理方法中，根据屏幕的方向，来确定列数

if (UIInterfaceOrientationIsPortrait(self.interfaceOrientation)) {

// 竖屏

return 3;

} else {

return 5;

}

3：MJRefresh:添加上拉刷新，下拉加载更多。两种方法1：block回调的方式 2：addTarget 方式来添加 。停止刷新：

[self.waterflowView headerEndRefreshing];

[self.waterflowView footerEndRefreshing];

4：GCD执行一次函数：

static dispatch_once_t onceToken;

dispatch_once(&onceToken, ^{

// 加载3.plist

NSArray *newShops = [HMShop objectArrayWithFilename:@"3.plist"];

[self.shops addObjectsFromArray:newShops];

});

5:在返回cell高度的方法中：要根据cell的宽度 和 图片的宽高比 算出 cell的高度。

HMShop *shop = self.shops[index];

// 根据cell的宽度 和 图片的宽高比 算出 cell的高度

return waterflowView.cellWidth * shop.h / shop.w;

6：cell的封装

 #import "HMWaterflowViewCell.h"
 @class HMWaterflowView, HMShop;

 @interface HMShopCell : HMWaterflowViewCell
 + (instancetype)cellWithWaterflowView:(HMWaterflowView *)waterflowView;

 @property (nonatomic, strong) HMShop *shop;
 @end

 #import "HMShopCell.h"
 #import "HMWaterflowView.h"
 #import "UIImageView+WebCache.h"
 #import "HMShop.h"

 @interface HMShopCell()
 @property (weak, nonatomic) UIImageView *imageView;
 @property (weak, nonatomic) UILabel *priceLabel;
 @end

 @implementation HMShopCell

 + (instancetype)cellWithWaterflowView:(HMWaterflowView *)waterflowView
 {
     static NSString *ID = @"SHOP";
     HMShopCell *cell = [waterflowView dequeueReusableCellWithIdentifier:ID];
     if (cell == nil) {
         cell = [[HMShopCell alloc] init];
         cell.identifier = ID;
     }
     return cell;
 }

 - (id)initWithFrame:(CGRect)frame
 {
     self = [super initWithFrame:frame];
     if (self) {

         UIImageView *imageView = [[UIImageView alloc] init];
         [self addSubview:imageView];
         self.imageView = imageView;

         UILabel *priceLabel = [[UILabel alloc] init];
         priceLabel.backgroundColor = [UIColor colorWithRed: green: blue: alpha:0.3];
         priceLabel.textAlignment = NSTextAlignmentCenter;
         priceLabel.textColor = [UIColor whiteColor];
         [self addSubview:priceLabel];
         self.priceLabel = priceLabel;
     }
     return self;
 }

 - (void)setShop:(HMShop *)shop
 {
     _shop = shop;

     self.priceLabel.text = shop.price;
     [self.imageView sd_setImageWithURL:[NSURL URLWithString:shop.img] placeholderImage:[UIImage imageNamed:@"loading"]];
 }

 - (void)layoutSubviews
 {
     [super layoutSubviews];

     self.imageView.frame = self.bounds;

     CGFloat priceX = ;
     CGFloat priceH = ;
     CGFloat priceY = self.bounds.size.height - priceH;
     CGFloat priceW = self.bounds.size.width;
     self.priceLabel.frame = CGRectMake(priceX, priceY, priceW, priceH);
 }

 @end

7：model的封装

 #import <Foundation/Foundation.h>

 @interface HMShop : NSObject
 @property (nonatomic, assign) CGFloat w;
 @property (nonatomic, assign) CGFloat h;
 @property (nonatomic, copy) NSString *img;
 @property (nonatomic, copy) NSString *price;
 @end

 #import "HMShop.h"

 @implementation HMShop

 @end