关于collectionview的初始化

Terminating app due to uncaught exception ‘NSInvalidArgumentException’, reason: ‘UICollectionView must be initialized with a non-nil layout parameter’

-(void)_initPhotoShowView{UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];[flowLayout setItemSize:CGSizeMake(kCellItemWidth, kCellItemWidth)];//cell item的大小flowLayout.minimumLineSpacing = kminimumLineSpacing;//每行的间距）flowLayout.minimumInteritemSpacing = kMinimumInteritemSpacing;//每行内部cell item的间距[flowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];//Scrolling direction（滚动方向）photoCollectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 64,kScreenWidth, kScreenHeight-64) collectionViewLayout:flowLayout];//一定要collectionViewLayout:flowLayout （Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'UICollectionView must be initialized with a non-nil layout parameter’）[photoCollectionView registerClass:[PhotoCollectionViewCell class] forCellWithReuseIdentifier:@"photoShowCell"];//进行Cell类的注册photoCollectionView.delegate = self;photoCollectionView.dataSource = self;photoCollectionView.contentInset = UIEdgeInsetsMake(2, 1, 1, 1);[self.view addSubview:photoCollectionView];}

，即使爬到最高的山上，一次也只能脚踏实地地迈一步。