重写init方法,创建布局参数- (id)init
{
[[UICollectionViewFlowLayout alloc] init];// 2.每个cell的尺寸
layout.itemSize = CGSizeMake(100, 100); return [super initWithCollectionViewLayout:layout];
}
注册cell(告诉collectionView将来创建怎样的cell)
[self.collectionView
registerClass:[UICollectionViewCell
class]
forCellWithReuseIdentifier:@"product"];
2. 从缓存池中取出cell
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"product" forIndexPath:indexPath];
return cell; }
• UICollectionViewFlowLayout称为”流水布局”,用来约束cell的显示
• 常见属性
➢
Cell的尺寸
@property
(nonatomic)
CGSize
itemSize;
➢ cell之间的水平间距
@property
(nonatomic)
CGFloat
minimumInteritemSpacing;
➢ cell之间的垂直间距
@property
(nonatomic)
CGFloat
minimumLineSpacing;
➢ 四周的内边距
@property
(nonatomic)
UIEdgeInsets
sectionInset;