iOS开发仿电商类APP首页实例

#import "MYIHomeViewController.h"

#import "MYIHomeHeaderView.h"
#import "JFConfigFile.h"
#import "MYIHomeLayout.h"
#import "MYIHomeCell.h"

static NSString *ID = @"collectionViewCell";

@interface MYIHomeViewController ()<UICollectionViewDelegate, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout>

@property (nonatomic, strong) UICollectionView *collectionView;

@end

@implementation MYIHomeViewController

- (void)viewDidLoad {
  [super viewDidLoad];

  //关闭自动调整滚动视图（不关闭图片轮播器会出现问题）
  self.automaticallyAdjustsScrollViewInsets = NO;
}

- (void)viewWillAppear:(BOOL)animated {
  [super viewWillAppear:animated];

  //隐藏navigationBar
  self.navigationController.navigationBar.hidden = YES;
}

- (void)loadView {
  [super loadView];

  //添加collectionView
  [self.view addSubview:self.collectionView];
}

//懒加载collectionView
- (UICollectionView *)collectionView {
  if (!_collectionView) {
    _collectionView = [[UICollectionView alloc] initWithFrame:[UIScreen mainScreen].bounds collectionViewLayout:[[MYIHomeLayout alloc] init]];
    _collectionView.backgroundColor = JFRGBColor(238, 238, 238);

    //注册cell
    [_collectionView registerClass:[MYIHomeCell class] forCellWithReuseIdentifier:ID];

    //注册UICollectionReusableView即headerView（切记要添加headerView一定要先注册）
    [_collectionView registerClass:[MYIHomeHeaderView class] forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"headerView"];

    _collectionView.delegate = self;
    _collectionView.dataSource = self;
  }
  return _collectionView;
}

#pragma mark ---UICollectionViewDataSource 数据源方法
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
  return 80;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
  MYIHomeCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:ID forIndexPath:indexPath];
  cell.iconName = @"goodsimagetest";
  cell.describe = @"蚂蚁到家蚂蚁到家蚂蚁到家";
  cell.currentPrice = @"¥100";
  cell.originalPrice = @"¥288";
  return cell;
}

//添加headerView
- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath {
  MYIHomeHeaderView *headerView = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"headerView" forIndexPath:indexPath];;

  //判断上面注册的UICollectionReusableView类型
  if (kind == UICollectionElementKindSectionHeader) {
    return headerView;
  }else {
    return nil;
  }
}

#pragma mark ---UICollectionViewDelegate
//设置headerView的宽高
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout referenceSizeForHeaderInSection:(NSInteger)section {

  return CGSizeMake(self.view.bounds.size.width, 380);
}

#pragma mark ---UICollectionViewDelegateFlowLayout

//设置collectionView的cell上、左、下、右的间距
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
  return UIEdgeInsetsMake(14, 0, 0, 0);
}

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

@end

- (void)viewDidLoad {
   [super viewDidLoad]; 

  //关闭自动调整滚动视图（不关闭图片轮播器会出现问题）
   self.automaticallyAdjustsScrollViewInsets = NO;
}

//注册UICollectionReusableView即headerView（切记要添加headerView一定要先注册）
    [_collectionView registerClass:[MYIHomeHeaderView class] forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"headerView"];

//添加headerView
- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath {
  MYIHomeHeaderView *headerView = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"headerView" forIndexPath:indexPath];

  //判断上面注册的UICollectionReusableView类型
  if (kind == UICollectionElementKindSectionHeader) {
    return headerView;
  }else {
    return nil;
  }
}