UICollectionView 的记录

创建

letlayout =UICollectionViewFlowLayout()

layout.minimumLineSpacing=8

layout.minimumInteritemSpacing=8

//layout.sectionInset = UIEdgeInsetsMake(8, 0, 0, 8)

//layout.itemSize = CGSizeMake(self.view.bounds.size.width - 0,172)

collectionView = HJMPullToRefreshCollectionView(frame:self.view.bounds, collectionViewLayout: layout)

collectionView.backgroundColor =UIColor(hexString:"#f0f0f0")

self.view.addSubview(collectionView)

collectionView.delegate =self

collectionView.dataSource =self

collectionView.registerClass(UICollectionViewCell.self, forCellWithReuseIdentifier: cellIdentify)

 总是记不住的 UICollectionViewDelegateFlowLayout

extensionStydyStatusViewController:UICollectionViewDelegateFlowLayout{

optionalpublicfunccollectionView(collectionView:UICollectionView, layout collectionViewLayout:UICollectionViewLayout, sizeForItemAtIndexPath indexPath:NSIndexPath) ->CGSize

@available(iOS6.0, *)

optionalpublicfunccollectionView(collectionView:UICollectionView, layout collectionViewLayout:UICollectionViewLayout, insetForSectionAtIndex section:Int) ->UIEdgeInsets

@available(iOS6.0, *)

optionalpublicfunccollectionView(collectionView:UICollectionView, layout collectionViewLayout:UICollectionViewLayout, minimumLineSpacingForSectionAtIndex section:Int) ->CGFloat

@available(iOS6.0, *)

optionalpublicfunccollectionView(collectionView:UICollectionView, layout collectionViewLayout:UICollectionViewLayout, minimumInteritemSpacingForSectionAtIndex section:Int) ->CGFloat

@available(iOS6.0, *)

optionalpublicfunccollectionView(collectionView:UICollectionView, layout collectionViewLayout:UICollectionViewLayout, referenceSizeForHeaderInSection section:Int) ->CGSize

@available(iOS6.0, *)

optionalpublicfunccollectionView(collectionView:UICollectionView, layout collectionViewLayout:UICollectionViewLayout, referenceSizeForFooterInSection section:Int) ->CGSize

}

UICollectionElementKindSectionHeader

UICollectionElementKindSectionFooter

// 自动布局的时候使用

layout.estimatedItemSize =CGSizeMake(self.view.bounds.size.width -0,172)

在Cell 中

//forces the system to do one layout pass

varisHeightCalculated:Bool=false

overridepublicfuncpreferredLayoutAttributesFittingAttributes(layoutAttributes:UICollectionViewLayoutAttributes) ->UICollectionViewLayoutAttributes{

//Exhibit A - We need to cache our calculation to prevent a crash.

if!isHeightCalculated{

setNeedsLayout()

layoutIfNeeded()

letsize =contentView.systemLayoutSizeFittingSize(layoutAttributes.size)

varnewFrame = layoutAttributes.frame

newFrame.size.width=CGFloat(ceilf(Float(size.width)))

newFrame.size.height=CGFloat(ceilf(Float(size.height)))

layoutAttributes.frame= newFrame

layoutAttributes.hidden=false

//isHeightCalculated = true

}

returnlayoutAttributes

}

使用自动布局是可能会有性能问题

UITableView ios8 以上

tableView.separatorStyle = .None

tableView.rowHeight =UITableViewAutomaticDimension

tableView.estimatedRowHeight =180