UICollectionViewController的使用

@interface UICollectionViewController : UIViewController <UICollectionViewDelegate, UICollectionViewDataSource>

使用步骤

第一步：必须有布局

UICollectionViewFlowLayout *collectionViewLayout = [[UICollectionViewFlowLayout alloc]init];
    [collectionViewLayout setMinimumLineSpacing:10];//垂直间距
    [collectionViewLayout setMinimumInteritemSpacing:1];//水平间距
    [collectionViewLayout setItemSize:CGSizeMake(75, 75)];
    //设置分组内边距
    UIEdgeInsets insets = UIEdgeInsetsMake(10, 0, 0, 0);
    [collectionViewLayout setSectionInset:(insets)];
 self = [super initWithCollectionViewLayout:collectionViewLayout];

第二部：cell必须自己注册

// Register cell classes  for use in creating new collection view cells.
  // [self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:reuseIdentifier];
   UINib *nib = [UINib nibWithNibName:@"HLProductCellCollectionViewCell" bundle:nil];
   [self.collectionView registerNib:nib forCellWithReuseIdentifier:reuseIdentifier];

错误分析：

如果没设置布局，即将报错：

1)'NSInvalidArgumentException', reason: 'UICollectionView must be initialized with a non-nil layout parameter'
            [HLProductCollectionViewController alloc]initWithCollectionViewLayout:( UICollectionViewLayout*)