我在 Table 视图中显示来自 JSON 的图像时遇到问题
I'm having troubles displaying an image from JSON in a Table View
我正在尝试显示来自 API 的图像。图片在 URL 中,我想用所有数组填充 Table 视图,但它在 Table 视图中只显示一张图片。
这是我的代码:
struct Autos {
let Marca:String
let Modelo:String
let Precio:String
let RutaImagen:String
init?(_ dict:[String:Any]?){
guard let _dict = dict,
let marca=_dict["Marca"]as?String,
let modelo=_dict["Modelo"]as?String,
let precio=_dict["Precio"]as?String,
let rutaImagen=_dict["RutaImagen"]as?String
else { return nil }
self.Marca = marca
self.Modelo = modelo
self.Precio = precio
self.RutaImagen = rutaImagen
}
}
var arrAutos = [Autos]()
func getImage(from string: String) -> UIImage? {
// Get valid URL
guard let url = URL(string: string)
else {
print("Unable to create URL")
return nil
}
var image: UIImage? = nil
do {
// Get valid data
let data = try Data(contentsOf: url, options: [])
// Make image
image = UIImage(data: data)
}
catch {
print(error.localizedDescription)
}
return image
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 9
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "carsCell", for: indexPath) as! CarsDetailTableViewCell
let url = URL(string: "http://ws-smartit.divisionautomotriz.com/wsApiCasaTrust/api/autos")!
let task = URLSession.shared.dataTask(with: url) {
(data, response, error) in
guard let dataResponse = data, error == nil else {
print(error?.localizedDescription ?? "Response Error")
return
}
do {
let jsonResponse = try JSONSerialization.jsonObject(with: dataResponse, options: []) as? NSArray
self.arrAutos = jsonResponse!.compactMap({ Autos([=12=] as? [String:String])})
DispatchQueue.main.async {
// Get valid string
let string = self.arrAutos[indexPath.row].RutaImagen
if let image = self.getImage(from: string) {
// Apply image
cell.imgCar.image = image
}
cell.lblBrand.text = self.arrAutos[indexPath.row].Marca
cell.lblPrice.text = self.arrAutos[indexPath.row].Precio
cell.lblModel.text = self.arrAutos[indexPath.row].Modelo
}
} catch let parsingError {
print("Error", parsingError)
}
}
task.resume()
return cell
}
JSON 序列化工作正常,因为其他数据在 table 视图中正确显示,问题出在图像上,因为在 table 视图中只出现一张图片,其他行是空的。有人有建议吗?
我认为您应该在加载 tableview 之前下载完整数据并在完成处理程序中重新加载 tableview。在 viewDidLoad()
.
中调用 loadData()
方法
fileprivate func loadData() {
let url = URL(string: "http://ws-smartit.divisionautomotriz.com/wsApiCasaTrust/api/autos")!
let task = URLSession.shared.dataTask(with: url) {
(data, response, error) in
guard let dataResponse = data, error == nil else {
print(error?.localizedDescription ?? "Response Error")
return
}
do {
let jsonResponse = try JSONSerialization.jsonObject(with: dataResponse, options: []) as? NSArray
self.arrAutos = jsonResponse!.compactMap({ Autos([=10=] as? [String:String])})
DispatchQueue.main.async {
self.tableView.reloadData()
}
} catch let parsingError {
print("Error", parsingError)
}
}
task.resume()
}
要在 tableView 单元格中加载图像,请在 background
线程中下载图像,然后在 main
线程中更新 imageView。
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "carsCell", for: indexPath) as! CarsDetailTableViewCell
// Get valid string
let string = self.arrAutos[indexPath.row].RutaImagen
//print(string)
cell.lblBrand.text = self.arrAutos[indexPath.row].Marca
cell.lblPrice.text = self.arrAutos[indexPath.row].Precio
cell.lblModel.text = self.arrAutos[indexPath.row].Modelo
let url = URL(string: string)
if url != nil {
DispatchQueue.global().async {
let data = try? Data(contentsOf: url!)
DispatchQueue.main.async {
if data != nil {
cell.imgCar.image = UIImage(data:data!)
}
}
}
}
return cell
}
希望这会奏效。
我正在尝试显示来自 API 的图像。图片在 URL 中,我想用所有数组填充 Table 视图,但它在 Table 视图中只显示一张图片。
这是我的代码:
struct Autos {
let Marca:String
let Modelo:String
let Precio:String
let RutaImagen:String
init?(_ dict:[String:Any]?){
guard let _dict = dict,
let marca=_dict["Marca"]as?String,
let modelo=_dict["Modelo"]as?String,
let precio=_dict["Precio"]as?String,
let rutaImagen=_dict["RutaImagen"]as?String
else { return nil }
self.Marca = marca
self.Modelo = modelo
self.Precio = precio
self.RutaImagen = rutaImagen
}
}
var arrAutos = [Autos]()
func getImage(from string: String) -> UIImage? {
// Get valid URL
guard let url = URL(string: string)
else {
print("Unable to create URL")
return nil
}
var image: UIImage? = nil
do {
// Get valid data
let data = try Data(contentsOf: url, options: [])
// Make image
image = UIImage(data: data)
}
catch {
print(error.localizedDescription)
}
return image
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 9
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "carsCell", for: indexPath) as! CarsDetailTableViewCell
let url = URL(string: "http://ws-smartit.divisionautomotriz.com/wsApiCasaTrust/api/autos")!
let task = URLSession.shared.dataTask(with: url) {
(data, response, error) in
guard let dataResponse = data, error == nil else {
print(error?.localizedDescription ?? "Response Error")
return
}
do {
let jsonResponse = try JSONSerialization.jsonObject(with: dataResponse, options: []) as? NSArray
self.arrAutos = jsonResponse!.compactMap({ Autos([=12=] as? [String:String])})
DispatchQueue.main.async {
// Get valid string
let string = self.arrAutos[indexPath.row].RutaImagen
if let image = self.getImage(from: string) {
// Apply image
cell.imgCar.image = image
}
cell.lblBrand.text = self.arrAutos[indexPath.row].Marca
cell.lblPrice.text = self.arrAutos[indexPath.row].Precio
cell.lblModel.text = self.arrAutos[indexPath.row].Modelo
}
} catch let parsingError {
print("Error", parsingError)
}
}
task.resume()
return cell
}
JSON 序列化工作正常,因为其他数据在 table 视图中正确显示,问题出在图像上,因为在 table 视图中只出现一张图片,其他行是空的。有人有建议吗?
我认为您应该在加载 tableview 之前下载完整数据并在完成处理程序中重新加载 tableview。在 viewDidLoad()
.
loadData()
方法
fileprivate func loadData() {
let url = URL(string: "http://ws-smartit.divisionautomotriz.com/wsApiCasaTrust/api/autos")!
let task = URLSession.shared.dataTask(with: url) {
(data, response, error) in
guard let dataResponse = data, error == nil else {
print(error?.localizedDescription ?? "Response Error")
return
}
do {
let jsonResponse = try JSONSerialization.jsonObject(with: dataResponse, options: []) as? NSArray
self.arrAutos = jsonResponse!.compactMap({ Autos([=10=] as? [String:String])})
DispatchQueue.main.async {
self.tableView.reloadData()
}
} catch let parsingError {
print("Error", parsingError)
}
}
task.resume()
}
要在 tableView 单元格中加载图像,请在 background
线程中下载图像,然后在 main
线程中更新 imageView。
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "carsCell", for: indexPath) as! CarsDetailTableViewCell
// Get valid string
let string = self.arrAutos[indexPath.row].RutaImagen
//print(string)
cell.lblBrand.text = self.arrAutos[indexPath.row].Marca
cell.lblPrice.text = self.arrAutos[indexPath.row].Precio
cell.lblModel.text = self.arrAutos[indexPath.row].Modelo
let url = URL(string: string)
if url != nil {
DispatchQueue.global().async {
let data = try? Data(contentsOf: url!)
DispatchQueue.main.async {
if data != nil {
cell.imgCar.image = UIImage(data:data!)
}
}
}
}
return cell
}
希望这会奏效。