学习文章
用CHTCollectionViewWaterfallLayout写瀑布流
效果
WaterFall.gif
源码
WaterfallCell.swift
import UIKit
let cellIdentifier = "WaterfallCell"
class WaterfallCell: UICollectionViewCell {
var showImageView: UIImageView?
override init(frame: CGRect) {
super.init(frame: frame)
let imageViewRect:CGRect = CGRect(x: 0, y: 0, width: CGRectGetMaxX(self.contentView.bounds), height: CGRectGetMaxY(self.contentView.bounds))
showImageView = UIImageView(frame: imageViewRect)
showImageView?.contentMode = .ScaleAspectFill
showImageView?.autoresizingMask = [.FlexibleHeight, .FlexibleWidth]
showImageView?.clipsToBounds = true
self.addSubview(showImageView!)
self.layer.borderWidth = 0.5
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
CollectionHeaderView.swift
import UIKit
let headerIdentifier = "WaterfallHeader"
class CollectionHeaderView: UICollectionReusableView {
override init(frame: CGRect) {
super.init(frame: frame)
self.layer.borderWidth = 1
self.backgroundColor = UIColor.redColor()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
CollectionFooterView.swift
import UIKit
let footerIdentifier = "WaterfallFooter"
class CollectionFooterView: UICollectionReusableView {
override init(frame: CGRect) {
super.init(frame: frame)
self.layer.borderWidth = 1
self.backgroundColor = UIColor.purpleColor()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
ViewController.swift
import UIKit
let sourceUrl = "http://www.duitang.com/album/1733789/masn/p/0/100/"
class ViewController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegate, CHTCollectionViewDelegateWaterfallLayout {
var collectionView : UICollectionView?
var dataSource : [AnyObject]? = Array()
var sizeSource : [AnyObject]? = Array()
var layout : CHTCollectionViewWaterfallLayout?
override func viewDidLoad() {
super.viewDidLoad()
buildCollectionView()
loadData()
}
func buildCollectionView() {
// 初始化布局
layout = CHTCollectionViewWaterfallLayout()
layout!.sectionInset = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10) // section 内边距
layout!.headerHeight = 40 // HeaderView高度
layout!.footerHeight = 40 // FooterView高度
layout!.columnCount = 3 // 几列显示
layout!.minimumColumnSpacing = 5 // cell之间的水平间距
layout!.minimumInteritemSpacing = 5 // cell之间的垂直间距
// 初始化CollectionView
collectionView = UICollectionView(frame: view.bounds, collectionViewLayout: layout!)
collectionView?.autoresizingMask = [.FlexibleWidth, .FlexibleHeight]
collectionView?.dataSource = self
collectionView?.delegate = self
collectionView?.backgroundColor = UIColor.whiteColor()
// 注册Cell HeaderView FooterView
collectionView?.registerClass(WaterfallCell.classForCoder(),
forCellWithReuseIdentifier: cellIdentifier)
collectionView?.registerClass(CollectionHeaderView.classForCoder(),
forSupplementaryViewOfKind: layout!.CHTCollectionElementKindSectionHeader, withReuseIdentifier: headerIdentifier)
collectionView?.registerClass(CollectionFooterView.classForCoder(),
forSupplementaryViewOfKind: layout!.CHTCollectionElementKindSectionFooter, withReuseIdentifier: footerIdentifier)
view.addSubview(collectionView!)
}
func loadData() {
GCDQueue.globalQueue .excute { () -> Void in
// 获取json数据
let data = NSData(contentsOfURL: NSURL(string: sourceUrl)!)
// 转换数据
if let jsonDic = try? NSJSONSerialization.JSONObjectWithData(data!, options: [.MutableContainers, .MutableLeaves]) as![String : AnyObject] {
let array = jsonDic["data"]!["blogs"] as! [AnyObject]
for value in array {
let temp = value as! [String : AnyObject]
print(temp["isrc"])
self.dataSource?.append(ImageModel(dictionary: temp)!)
}
}
// 主线程更新
GCDQueue.mainQueue.excute({ () -> Void in
self.collectionView?.reloadData()
})
}
}
// MARK: UICollectionViewDataSource
func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return (dataSource?.count)!
}
func numberOfSectionsInCollectionView(collectionView: UICollectionView) -> Int {
return 2
}
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
let waterCell = collectionView.dequeueReusableCellWithReuseIdentifier(cellIdentifier, forIndexPath: indexPath) as! WaterfallCell
let imageModel : ImageModel = self.dataSource![indexPath.row] as! ImageModel;
waterCell.showImageView?.sd_setImageWithURL(NSURL(string: imageModel.isrc!));
return waterCell
}
func collectionView(collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, atIndexPath indexPath: NSIndexPath) -> UICollectionReusableView {
var reusableView : UICollectionReusableView?
if kind == layout!.CHTCollectionElementKindSectionHeader {
reusableView = collectionView.dequeueReusableSupplementaryViewOfKind(kind, withReuseIdentifier: headerIdentifier, forIndexPath: indexPath)
} else {
reusableView = collectionView.dequeueReusableSupplementaryViewOfKind(kind, withReuseIdentifier: footerIdentifier, forIndexPath: indexPath)
}
return reusableView!
}
// MARK: CHTCollectionViewDelegateWaterfallLayout
func collectionView (collectionView: UICollectionView,layout collectionViewLayout: UICollectionViewLayout,
sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {
let imageModel : ImageModel = self.dataSource![indexPath.row] as! ImageModel
return CGSize(width: CGFloat(imageModel.iwd!), height: CGFloat(imageModel.iht!))
}
}
