class UICollectionView : UIScrollView
//初始化，位置，风格 init(frame: CGRect, collectionViewLayout layout: UICollectionViewLayout) //布局风格
var collectionViewLayout: UICollectionViewLayout
//代理
unowned(unsafe) var delegate: UICollectionViewDelegate?
//数据源
unowned(unsafe) var dataSource: UICollectionViewDataSource?
//背景视图
var backgroundView: UIView?
func registerClass(cellClass: AnyClass?, forCellWithReuseIdentifier identifier: String)
func registerNib(nib: UINib?, forCellWithReuseIdentifier identifier: String)
func registerClass(viewClass: AnyClass?, forSupplementaryViewOfKind elementKind: String, withReuseIdentifier identifier: String)
func registerNib(nib: UINib?, forSupplementaryViewOfKind kind: String, withReuseIdentifier identifier: String)
func dequeueReusableCellWithReuseIdentifier(identifier: String, forIndexPath indexPath: NSIndexPath!) -> AnyObject
func dequeueReusableSupplementaryViewOfKind(elementKind: String, withReuseIdentifier identifier: String, forIndexPath indexPath: NSIndexPath!) -> AnyObject
var allowsSelection: Bool // default is YES
var allowsMultipleSelection: Bool // default is NO//返回被选中的items
func indexPathsForSelectedItems() -> [AnyObject] // returns nil or an array of selected index paths
//选中弄个indexpath， 是否有动画，
func selectItemAtIndexPath(indexPath: NSIndexPath?, animated: Bool, scrollPosition: UICollectionViewScrollPosition)
//取消选中
func deselectItemAtIndexPath(indexPath: NSIndexPath?, animated: Bool)
//刷新数据
func reloadData()
func setCollectionViewLayout(layout: UICollectionViewLayout, animated: Bool)
func setCollectionViewLayout(layout: UICollectionViewLayout, animated: Bool)
@availability(iOS, introduced=7.0)
func setCollectionViewLayout(layout: UICollectionViewLayout, animated: Bool, completion: ((Bool) -> Void)!)
@availability(iOS, introduced=7.0)
func startInteractiveTransitionToCollectionViewLayout(layout: UICollectionViewLayout, completion: UICollectionViewLayoutInteractiveTransitionCompletion?) -> UICollectionViewTransitionLayout
@availability(iOS, introduced=7.0)
func finishInteractiveTransition()
@availability(iOS, introduced=7.0)
func cancelInteractiveTransition()
//有几个
func numberOfSections() -> Int
//每个有多少行
func numberOfItemsInSection(section: Int) -> Int
func layoutAttributesForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes?
func layoutAttributesForSupplementaryElementOfKind(kind: String, atIndexPath indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes?
func indexPathForItemAtPoint(point: CGPoint) -> NSIndexPath?
func indexPathForCell(cell: UICollectionViewCell) -> NSIndexPath?
func cellForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewCell?
func visibleCells() -> [AnyObject]
func indexPathsForVisibleItems() -> [AnyObject]
//滚动到indespath位置
func scrollToItemAtIndexPath(indexPath: NSIndexPath, atScrollPosition scrollPosition: UICollectionViewScrollPosition, animated: Bool)
//插入
func insertSections(sections: NSIndexSet)
//删除 func deleteSections(sections: NSIndexSet)
//重载弄个
func reloadSections(sections: NSIndexSet)
//移动
func moveSection(section: Int, toSection newSection: Int)
func performBatchUpdates(updates: (() -> Void)?, completion: ((Bool) -> Void)?)
extension NSIndexPath {
init!(forItem item: Int, inSection section: Int) -> NSIndexPath
@availability(iOS, introduced=6.0)
var item: Int { get }
}