以编程方式将图像从 api 添加到 CustomCell 变得越来越滞后

Question

我的表格视图在滚动时变慢，我有一个自定义单元格和一个表格视图：

我有这个控制器，在其中进行 api 调用并填充行程数组，然后在 cellForRowAt im 中创建单元格

class HistorialViewController: UIViewController , UITableViewDataSource, UITableViewDelegate  {
@IBOutlet weak var historialTableView: UITableView!
var trips = [RootClass]()
override func viewDidLoad() {
super.viewDidLoad()
self.historialTableView.delegate = self
self.historialTableView.dataSource = self
self.historialTableView.register(CustomCellHistorial.self, forCellReuseIdentifier: cellId)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
print("coming back")
self.fetchTrips()
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = self.historialTableView.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as! CustomCellHistorial
let trip = self.trips[indexPath.row]
cell.trip = trip
return cell
}
private func fetchTrips(){
AFWrapper.getTripHistory( success: { (jsonResponse) in
self.trips = []
for item in jsonResponse["trips"].arrayValue {
self.trips.append(RootClass(fromJson:item))
}
self.reloadTrips()
Timer.scheduledTimer(withTimeInterval: 2.0, repeats: false) { (nil) in
self.indicator.stopAnimating()
}
}, failure: { (error) -> Void in
print(error)
})
}
func reloadTrips(){
DispatchQueue.main.async{
self.historialTableView.reloadData()
}
}

这是我的自定义单元格

class CustomCellHistorial : UITableViewCell{
var trip: RootClass? {
didSet{
dateTimeLabel.text = returnCleanDate(fecha: trip!.createdAt)
distanceAndTimeLabel.text = returnDistanceAndTime(distance: (trip?.trip!.real!.dist!)!, time: (trip?.trip!.real!.time)!)
priceLabel.text = returnCleanPrice(price: (trip?.trip!.real!.price!)!)
ratedLabel.text = "Not Rated"
self.productImage.image = self.returnDriverImage(photoUrl: (self.trip?.driver!.photo!)!)
if (trip!.score) != nil {
let score = trip!.score
if (score?.driver) != nil{
if(trip!.score!.driver!.stars! != 0.0 ){
ratedLabel.isHidden = true
}else{
ratedLabel.isHidden = false
}
}else{
print("yei")
}
}
}
}
private func returnDriverImage(photoUrl: String) -> UIImage{
let url = URL(string: photoUrl)
do {
let data = try Data(contentsOf: url!)
if let roundedimg = UIImage(data: data){
let croppedImageDriver = roundedimg.resize(toTargetSize: self.productImage.frame.size)
return croppedImageDriver
}
} catch let error {
debugPrint("ERRor :: (error)")
let image = UIImage(named: "perfilIcono")
return image!
}
let image = UIImage(named: "perfilIcono")
return image!
}

我找到的答案是针对旧版本的 Swift，以及它们在故事板中制作表格视图的方式，或者它们不处理自定义单元格。

我认为问题出在返回驱动程序图像功能上。

Answer 1

此行

let data = try Data(contentsOf: url!)

您从

self.productImage.image = self.returnDriverImage(photoUrl: (self.trip?.driver!.photo!)!)

阻止主线程并在滚动时多次重新下载同一图像，请考虑使用SDWebImage