在swift开发中，会遇到页面无数据的情况，当没有数据时，页面一片空白，顿时令用户心情很不好，在OC中自己定义的占位图View不免有点太low，于是采用第三方占位图框架DZNEmptyDataSet，如今在swift中也需要使用此此景，下面就介绍一下如何在swift中使用DZNEmptyDataSet。
OC版本的 DZNEmptyDataSet gitHub传送门 :DZNEmptyDataSet
DZNEmptyDataSet swift 使用方法的传送门DZNEmptyDataSetSwift
1.新建swift工程，并导入第三方
$ pod init
在Podfile中添加 DZNEmptyDataSet三方框架
use_frameworks!
#占位图
pod 'DZNEmptyDataSet'
然后pod install
新建swift工程，并导入第三方
2.创建一个OC转swift的桥接对象文件
24B06FC5-2FC0-4A46-A8A0-568E7010C2C4.png
72CEB3CC-FF08-43DB-B56E-71AD8B38FC8C.png
3.新建一个viewController，添加tableView 设置emptyData代理
fileprivate lazy var tableView: UITableView = {[weak self] in
let tableView = UITableView()
tableView.backgroundColor = UIColor(red: 240/255.0, green: 240/255.0, blue: 240/255.0, alpha: 1.0)
tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
tableView.separatorStyle = .none
tableView.emptyDataSetSource = self
tableView.emptyDataSetDelegate = self
tableView.delegate = self;
tableView.dataSource = self;
return tableView
}()
4.实现代理协议
extension ViewController: DZNEmptyDataSetSource,DZNEmptyDataSetDelegate,UITableViewDelegate,UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return cellCount
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: .default, reuseIdentifier: "cell")
cell.textLabel?.text = "\(indexPath.row)"
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
//MARK: -- DZNEmptyDataSetSource Methods
//标题为空的数据集
func title(forEmptyDataSet scrollView: UIScrollView!) -> NSAttributedString! {
let text = "没有数据";
let attributes = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: CGFloat(18.0)), NSForegroundColorAttributeName: UIColor.blue]
return NSAttributedString(string: text, attributes: attributes)
}
//描述为空的数据集
func description(forEmptyDataSet scrollView: UIScrollView!) -> NSAttributedString! {
let paragraph = NSMutableParagraphStyle()
paragraph.alignment = .center
paragraph.lineSpacing = CGFloat(NSLineBreakMode.byWordWrapping.rawValue)
let attributes = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: CGFloat(15.0)), NSForegroundColorAttributeName: UIColor.red, NSParagraphStyleAttributeName: paragraph]
return NSAttributedString(string: "真的没有数据！", attributes: attributes)
}
////空数据按钮图片
func image(forEmptyDataSet scrollView: UIScrollView!) -> UIImage! {
if isLoading! { //加载动画图片
return UIImage(named: "youku_refreshing")
} else {
return UIImage(named: "placeholder_instagram")
}
}
//数据集加载动画
func imageAnimation(forEmptyDataSet scrollView: UIScrollView!) -> CAAnimation! {
let animation = CABasicAnimation(keyPath: "transform")
animation.fromValue = NSValue(caTransform3D: CATransform3DIdentity)
animation.toValue = NSValue(caTransform3D: CATransform3DMakeRotation(CGFloat(Double.pi / 2), 0.0, 0.0, 1.0))
animation.duration = 0.25
animation.isCumulative = true
animation.repeatCount = MAXFLOAT
return animation as CAAnimation
}
//按钮标题为空的数据集
func buttonTitle(forEmptyDataSet scrollView: UIScrollView!, for state: UIControlState) -> NSAttributedString! {
let attributes = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: CGFloat(16.0)), NSForegroundColorAttributeName: (state == UIControlState.normal) ? UIColor.brown : UIColor.green]
return NSAttributedString(string: "重新加载", attributes: attributes)
}
////重新加载按钮背景图片
func buttonBackgroundImage(forEmptyDataSet scrollView: UIScrollView!, for state: UIControlState) -> UIImage! {
let image = UIImage(named: state == UIControlState.normal ? "button_background_foursquare_normal" : "button_background_foursquare_highlight")
return image?.resizableImage(withCapInsets: UIEdgeInsetsMake(25.0, 25.0, 25.0, 25.0), resizingMode: .stretch).withAlignmentRectInsets(UIEdgeInsetsMake(0.0, 10.0, 0.0, 10.0))
}
func backgroundColor(forEmptyDataSet scrollView: UIScrollView!) -> UIColor! {
return UIColor(red: 240/255.0, green: 240/255.0, blue: 240/255.0, alpha: 1.0)
}
func verticalOffset(forEmptyDataSet scrollView: UIScrollView!) -> CGFloat {
return 0
}
func spaceHeight(forEmptyDataSet scrollView: UIScrollView!) -> CGFloat {
return 10
}
//MARK: -- DZNEmptyDataSetDelegate
func emptyDataSetShouldDisplay(_ scrollView: UIScrollView!) -> Bool {
return true
}
func emptyDataSetShouldAllowTouch(_ scrollView: UIScrollView!) -> Bool {
return true
}
func emptyDataSetShouldAllowScroll(_ scrollView: UIScrollView!) -> Bool {
return true
}
func emptyDataSetShouldAnimateImageView(_ scrollView: UIScrollView!) -> Bool {
return self.isLoading!
}
func emptyDataSet(_ scrollView: UIScrollView!, didTap view: UIView!) {
isLoading = true
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 3) {
self.isLoading = false
self.reloadTableView()
}
}
func emptyDataSet(_ scrollView: UIScrollView!, didTap button: UIButton!) {
self.isLoading = true
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 3) {
self.isLoading = false
self.cellCount = 10
self.reloadTableView()
}
}
fileprivate func reloadTableView(){
self.tableView.reloadData()
self.tableView.reloadEmptyDataSet()
}
}
5.附上完整代码
extension ViewController: DZNEmptyDataSetSource,DZNEmptyDataSetDelegate,UITableViewDelegate,UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return cellCount
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: .default, reuseIdentifier: "cell")
cell.textLabel?.text = "\(indexPath.row)"
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
//MARK: -- DZNEmptyDataSetSource Methods
//标题为空的数据集
func title(forEmptyDataSet scrollView: UIScrollView!) -> NSAttributedString! {
let text = "没有数据";
let attributes = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: CGFloat(18.0)), NSForegroundColorAttributeName: UIColor.blue]
return NSAttributedString(string: text, attributes: attributes)
}
//描述为空的数据集
func description(forEmptyDataSet scrollView: UIScrollView!) -> NSAttributedString! {
let paragraph = NSMutableParagraphStyle()
paragraph.alignment = .center
paragraph.lineSpacing = CGFloat(NSLineBreakMode.byWordWrapping.rawValue)
let attributes = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: CGFloat(15.0)), NSForegroundColorAttributeName: UIColor.red, NSParagraphStyleAttributeName: paragraph]
return NSAttributedString(string: "真的没有数据！", attributes: attributes)
}
////空数据按钮图片
func image(forEmptyDataSet scrollView: UIScrollView!) -> UIImage! {
if isLoading! { //加载动画图片
return UIImage(named: "youku_refreshing")
} else {
return UIImage(named: "placeholder_instagram")
}
}
//数据集加载动画
func imageAnimation(forEmptyDataSet scrollView: UIScrollView!) -> CAAnimation! {
let animation = CABasicAnimation(keyPath: "transform")
animation.fromValue = NSValue(caTransform3D: CATransform3DIdentity)
animation.toValue = NSValue(caTransform3D: CATransform3DMakeRotation(CGFloat(Double.pi / 2), 0.0, 0.0, 1.0))
animation.duration = 0.25
animation.isCumulative = true
animation.repeatCount = MAXFLOAT
return animation as CAAnimation
}
//按钮标题为空的数据集
func buttonTitle(forEmptyDataSet scrollView: UIScrollView!, for state: UIControlState) -> NSAttributedString! {
let attributes = [NSFontAttributeName: UIFont.boldSystemFont(ofSize: CGFloat(16.0)), NSForegroundColorAttributeName: (state == UIControlState.normal) ? UIColor.brown : UIColor.green]
return NSAttributedString(string: "重新加载", attributes: attributes)
}
////重新加载按钮背景图片
func buttonBackgroundImage(forEmptyDataSet scrollView: UIScrollView!, for state: UIControlState) -> UIImage! {
let image = UIImage(named: state == UIControlState.normal ? "button_background_foursquare_normal" : "button_background_foursquare_highlight")
return image?.resizableImage(withCapInsets: UIEdgeInsetsMake(25.0, 25.0, 25.0, 25.0), resizingMode: .stretch).withAlignmentRectInsets(UIEdgeInsetsMake(0.0, 10.0, 0.0, 10.0))
}
func backgroundColor(forEmptyDataSet scrollView: UIScrollView!) -> UIColor! {
return UIColor(red: 240/255.0, green: 240/255.0, blue: 240/255.0, alpha: 1.0)
}
func verticalOffset(forEmptyDataSet scrollView: UIScrollView!) -> CGFloat {
return 0
}
func spaceHeight(forEmptyDataSet scrollView: UIScrollView!) -> CGFloat {
return 10
}
//MARK: -- DZNEmptyDataSetDelegate
func emptyDataSetShouldDisplay(_ scrollView: UIScrollView!) -> Bool {
return true
}
func emptyDataSetShouldAllowTouch(_ scrollView: UIScrollView!) -> Bool {
return true
}
func emptyDataSetShouldAllowScroll(_ scrollView: UIScrollView!) -> Bool {
return true
}
func emptyDataSetShouldAnimateImageView(_ scrollView: UIScrollView!) -> Bool {
return self.isLoading!
}
func emptyDataSet(_ scrollView: UIScrollView!, didTap view: UIView!) {
isLoading = true
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 3) {
self.isLoading = false
self.reloadTableView()
}
}
func emptyDataSet(_ scrollView: UIScrollView!, didTap button: UIButton!) {
self.isLoading = true
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 3) {
self.isLoading = false
self.cellCount = 10
self.reloadTableView()
}
}
fileprivate func reloadTableView(){
self.tableView.reloadData()
self.tableView.reloadEmptyDataSet()
}
}
