swift4.0 CollectionView和自定义cell
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本文有snapkit三方布局的使用，类似于masonry，自己了解一下
另外用懒加载的方法添加了表头
一、CollectionView和协议实现
//
// HomeViewController.swift
// SwiftTest18-1-5
//
// Created by QC on 2018/1/8.
// Copyright © 2018年 BoYaXun. All rights reserved.
//
/*
*本类主要实现collectionView
*动态布局
*这个类我还准备测试一下网络数据请求
*/
import UIKit
class HomeViewController: UIViewController,UICollectionViewDataSource,UICollectionViewDelegate,UICollectionViewDelegateFlowLayout {
override func viewDidLoad() {
super.viewDidLoad()
self.view.backgroundColor =RGBA(r:242, g: 242, b: 242, a: 1)
// Do any additional setup after loading the view.
self.title ="首页"
myCollectionView()
}
func myCollectionView() {
//自定义item的FlowLayout
let flowLayout =UICollectionViewFlowLayout()
//设置item的size
flowLayout.itemSize = CGSize.init(width:CKWIDTH/4,height:CKWIDTH/4)
//设置item的排列方式
flowLayout.scrollDirection =UICollectionViewScrollDirection.vertical
//设置item的四边边距
flowLayout.sectionInset =UIEdgeInsetsMake(10,0, 10, 0)
//列间距
flowLayout.minimumLineSpacing =0
//行间距
flowLayout.minimumInteritemSpacing =0
//设置页头尺寸
//flowLayout.headerReferenceSize = CGSize.init(width:,height:)
//设置页尾尺寸
//flowLayout.footerReferenceSize = CGSize.init(width: , height: )
//自定义uicollectionview的位置
let collectionView = UICollectionView(frame: CGRect.init(x:0, y:64, width: CKWIDTH, height: CKHEIGHT - 64),collectionViewLayout:flowLayout)
self.view.addSubview(collectionView)
//设置背景颜色
collectionView.backgroundColor =RGBA(r:242, g: 242, b: 242, a: 1)
//设置垂直滚动是否滚到item的最底部
collectionView.alwaysBounceVertical =true
//设置水平滚动是否滚到item的最右边
collectionView.alwaysBounceHorizontal =true
//设置数据源对象
collectionView.dataSource =self
//设置代理对象
collectionView.delegate =self
//设置uicollectionView的单元格点击
collectionView.allowsSelection =true
//设置uicollectionView的单元格多选
collectionView.allowsMultipleSelection =false
//开启uicollectionView的分页显示效果
collectionView.isPagingEnabled =true
//注册uicollectionviewcell
collectionView.register(HomeCollectionViewCell.self, forCellWithReuseIdentifier:"cell")
collectionView.register(UICollectionReusableView.self, forSupplementaryViewOfKind:UICollectionElementKindSectionHeader, withReuseIdentifier:"reusable")
}
func numberOfSections(in collectionView:UICollectionView) ->Int {
return 1
}
func collectionView(_ collectionView:UICollectionView, numberOfItemsInSection section:Int) -> Int {
return 3
}
func collectionView(_ collectionView:UICollectionView, cellForItemAt indexPath:IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier:"cell", for: indexPath)
return cell
}
//分区头高度
func collectionView(_ collectionView:UICollectionView, layout collectionViewLayout:UICollectionViewLayout, referenceSizeForHeaderInSection section:Int) -> CGSize {
return CGSize.init(width: CKWIDTH, height:200)
}
//分区头设置
func collectionView(_ collectionView:UICollectionView, viewForSupplementaryElementOfKind kind:String, at indexPath:IndexPath) ->UICollectionReusableView {
var reusableview:UICollectionReusableView!
if kind ==UICollectionElementKindSectionHeader{
reusableview = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier:"reusable", for: indexPath)
reusableview.addSubview(headerImage)
}
return reusableview
}
//懒加载一个imageView
lazy var headerImage:UIImageView = {
let headerImage = UIImageView()
headerImage.setImageWith(nil, placeholder:UIImage(named:"cat"))
headerImage.frame = CGRect.init(x:0,y:0,width:CKWIDTH,height:200)
return headerImage
}()
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
}
二 、自定义cell
//
// HomeCollectionViewCell.swift
// SwiftTest18-1-5
//
// Created by QC on 2018/1/11.
// Copyright © 2018年 BoYaXun. All rights reserved.
//
import UIKit
class HomeCollectionViewCell: UICollectionViewCell {
var titleLabel:UILabel?
var imageView:UIImageView?
override init(frame: CGRect) {
super.init(frame: frame)
let cellWidth:CGFloat =self.frame.size.width
let cellHeight:CGFloat =self.frame.size.height
self.imageView =UIImageView()
self.addSubview(self.imageView!)
self.imageView?.snp.makeConstraints({ (make)in
make.centerX.equalTo(self)
make.centerY.equalTo(self).offset(-10)
make.width.equalTo(cellWidth/3)
make.height.equalTo(cellHeight/3)
})
self.imageView?.setImageWith(nil, placeholder:UIImage(named:"cat"))
self.titleLabel =UILabel()
self.addSubview(self.titleLabel!)
self.titleLabel?.snp.makeConstraints({ (make)in
make.centerX.equalTo(self)
make.top.equalTo((self.imageView?.snp.bottom)!).offset(10)
make.width.equalTo(width)
make.height.equalTo(13)
})
self.titleLabel?.font =UIFont.systemFont(ofSize:13)
self.titleLabel?.text ="新闻中心"
self.titleLabel?.textAlignment =NSTextAlignment.center
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}