collectionview 实现的瀑布流（IOS ）

CHTCollectionViewWaterfallLayout =============================== [](http://cocoadocs.org/docsets/CHTCollectionViewWaterfallLayout) [](http://cocoadocs.org/docsets/CHTCollectionViewWaterfallLayout) [](https://travis-ci.org/chiahsien/CHTCollectionViewWaterfallLayout) **CHTCollectionViewWaterfallLayout** is a subclass of [UICollectionViewLayout], and it trys to imitate [UICollectionViewFlowLayout]'s usage as much as possible. This layout is inspired by [Pinterest]. It also is compatible with [PSTCollectionView]. Screen Shots ------------  Features -------- * Easy to use, it trys to imitate [UICollectionViewFlowLayout]'s usage as much as possible. * Highly customizable. * Outstanding performance, try 10,000+ items and see the smoothness for yourself. * Support header and footer views. Prerequisite ------------ * ARC * Xcode 4.4+, which supports literals syntax. * iOS 6+, or * iOS 4.x/5.x, with [PSTCollectionView]. How to install -------------- * [CocoaPods] Add `pod 'CHTCollectionViewWaterfallLayout'` to your podfile. * Manual Copy `CHTCollectionViewWaterfallLayout.h/m` to your project. How to Use ---------- Read the demo codes and `CHTCollectionViewWaterfallLayout.h` header file for more information. #### Step 1 Below lists the properties for you to customize the layout. Although they have default values, I strongly recommand you to set up at least the `columnCount` property to suit your needs. The `itemRenderDirection` property is an enum which decides the order in which your items will be rendered in subsequent rows. For eg. Left-Right | Right-Left | Shortest column filling up first. ``` objc @property (nonatomic, assign) NSInteger columnCount; @property (nonatomic, assign) CGFloat minimumColumnSpacing; @property (nonatomic, assign) CGFloat minimumInteritemSpacing; @property (nonatomic, assign) CGFloat headerHeight; @property (nonatomic, assign) CGFloat footerHeight; @property (nonatomic, assign) UIEdgeInsets sectionInset; @property (nonatomic, assign) ItemRenderDirection itemRenderDirection; ``` #### Step 2 Your collection view's delegate (which often is your view controller) must conforms to `CHTCollectionViewDelegateWaterfallLayout` protocol and implements the required method, all you need to do is return the original size of the item: ``` objc - (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath; ``` #### Step 3 (Optional) If you need to support iOS 4.x/5.x and you have installed [PSTCollectionView], then you **NEED** to modify some codes. Quoted from [PSTCollectionView] README file: > **If you want to have PSTCollectionView on iOS4.3/5.x and UICollectionView on iOS6, use PSUICollectionView (basically add PS on any UICollectionView* class to get auto-support for older iOS versions)** > If you always want to use PSTCollectionView, use PSTCollectionView as class names. (replace the UI with PST) Limitation ---------- * Only vertical scrolling is supported. * No decoration view. Who is using it --------------- Please let me know if your app is using this library. I'm glad to put your app on the list :-) * [F3PiX](https://itunes.apple.com/us/app/samenwerken-f3pix/id897714553?mt=8) F3PiX is a series of apps which gives you a concise, curated collection of pictures by professional (Dutch) photographers according to a specific theme. You can use the pictures freely for your own work. License ------- CHTCollectionViewWaterfallLayout is available under the MIT license. See the LICENSE file for more info. Changelog --------- Refer to the [Releases page](https://github.com/chiahsien/CHTCollectionViewWaterfallLayout/releases). [UICollectionViewLayout]: http://developer.apple.com/library/ios/#documentation/uikit/reference/UICollectionViewLayout_class/Reference/Reference.html [UICollectionViewFlowLayout]: https://developer.apple.com/library/ios/documentation/uikit/reference/UICollectionViewFlowLayout_class/Reference/Reference.html [Pinterest]: http://pinterest.com/ [PSTCollectionView]: https://github.com/steipete/PSTCollectionView [CocoaPods]: http://cocoapods.org/