【发布时间】：2019-04-11 17:09:32
【问题描述】：
我有两个下载数据的 URL，它们给了我这种类型的 json：
1) http://192.168.178.77/MyWebService/api/getteams.php
R ->
{"teams":
[{"id":1,"name":"Avengers","member":7},{"id":2,"name":"Fantastics4","member":4},{"id":3,"name":"test","member":6},{"id":4,"name":"teamtest","member":33},{"id":5,"name":"inserisco","member":33},{"id":6,"name":"sarto","member":33},
{"id":7,"name":"name","member":22},
{"id":8,"name":"test","member":999}]
}
2)http://127.0.0.1/MyWebService/api/fetch_image.php?id_team=1 //其中id_team param是从第一个网址下载的id
R -> {"image_team":[{"id":4,"img_path":"http:\/\/localhost\/MyWebService\/images\/imgTest.png","id_team":1}]}
现在，为了下载这些数据，我迅速创建了类和函数来包含和下载数据。
位于各自 file.swift 中的 2 个类是：
1)在 TeamJson.swift 中：
import Foundation
class ClassJsonTeam: Codable {
private var teams: [JsonTeam]
init(teams: [JsonTeam]) {
self.teams = teams
}
func getTeams()-> [JsonTeam]{
return(self.teams);
}
func setTeams(teams:[JsonTeam]){
self.teams = teams;
}
}
class JsonTeam: Codable {
private let id: Int
private var name: String
private var member: Int
init(id: Int, name: String, member: Int) {
self.id = id
self.name = name
self.member = member
}
func getId()->Int{
return(self.id);
}
func setId(id:Int){
self.member = id;
}
func getName()->String{
return(self.name);
}
func setName(name:String){
self.name = name;
}
func getMembers()->Int{
return(self.member);
}
func setMembers(members:Int){
self.member = members;
}
}
2) 在 ImageJsonTeam.swift 中
import Foundation
class ClassJsonTeamImage : Codable {
private var teams : [JsonTeamImg]
init(teams: [JsonTeamImg]) {
self.teams = teams
}
func getTeamsImg()-> [JsonTeamImg]{
return(self.teams);
}
func setTeamsImg(teams:[JsonTeamImg]){
self.teams = teams;
}
}
class JsonTeamImg : Codable{
private var id : Int
private var imagePath: URL
private var teamId : Int
init(id : Int, imagePath : URL , teamId : Int) {
self.id = id
self.imagePath = imagePath
self.teamId = teamId
}
func getId() -> Int{
return(self.id)
}
func setId(id : Int){
self.id = id
}
func getImagePath() -> URL {
return(self.imagePath)
}
func setImagePath(imagePath : URL){
self.imagePath = imagePath
}
func getTeamId()-> Int{
return(self.teamId)
}
func setTeamId(teamId : Int){
self.teamId = teamId
}
}
另外，由于我需要合并两个json中的信息，所以我创建了这个类型的第三个类：
3)CompleteTeamJson.swift
import Foundation
public class ClassJsonCompleteTeam{
private var team : [JsonCompleteTeam]
init(team : [JsonCompleteTeam]){
self.team = team
}
}
public class JsonCompleteTeam{
private var id : Int
private var name : String
private var member : Int
private var imgUrl : URL
init(id: Int, name: String, member: Int, imgUrl: URL) {
self.id = id
self.name = name
self.member = member
self.imgUrl = imgUrl
}
func getId()->Int{
return(self.id);
}
func setId(id:Int){
self.member = id;
}
func getName()->String{
return(self.name);
}
func setName(name:String){
self.name = name;
}
func getMembers()->Int{
return(self.member);
}
func setMembers(members:Int){
self.member = members;
}
func getImageUrl() -> URL {
return(self.imgUrl)
}
func setImagePath(imgUrl : URL){
self.imgUrl = imgUrl
}
}
现在，我的 viewController 中的情况是这样的：
import UIKit
//var teamCollection : ClassJsonTeam!
//
class ViewController: UIViewController {
@IBAction func InsertNewTeamButton(_ sender: Any) {
performSegue(withIdentifier: "NewTeamSegue", sender: self)
}
var teams: [JsonTeam]?
var teamsImg : [JsonTeamImg]?
var teamsComplete : [JsonCompleteTeam]?
override func viewDidLoad() {
super.viewDidLoad()
downloadTeams(completion: { (teams) in
self.teams = teams
for index in (0...(self.teams!.count - 1)){
self.downloadTeamsImage(idTeam: teams[index].getId(), completion:
{(teamsImg) in self.teamsImg = teamsImg
})
let finalId : Int = teams[index].getId()
let finalName : String = teams[index].getName()
let finalMember : Int = teams[index].getMembers()
var finalURL : URL = URL(string : "http://localhost/MyWebService/images/EmptyImg.png")!
for index2 in (0...(self.teamsImg!.count - 1)){
if (finalId == self.teamsImg![index2].getId()){
finalURL = self.teamsImg![index2].getImagePath()
}
}
let tempCompleteTeam = JsonCompleteTeam(id: finalId, name: finalName, member: finalMember, imgUrl: finalURL)
self.teamsComplete?.append(tempCompleteTeam)
}
//self.InsertNewTeamButton((Any).self)
self.showTeamButton((Any).self)
})
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// somethings in new wc //
}
@IBAction func showTeamButton(_ sender: Any) {
performSegue(withIdentifier: "TeamListSegue", sender: self)
}
func downloadTeams(completion: @escaping (([JsonTeam]) -> Void)) {
//get teams with classes
let getTeamUrl = "http://192.168.178.77/MyWebService/api/getteams.php"
guard let urlTeam = URL(string: getTeamUrl) else { return }
URLSession.shared.dataTask(with: urlTeam) { (data,response,err) in
guard let data = data else {return}
do {
let team = try JSONDecoder().decode(ClassJsonTeam.self, from: data)
var tempArrayTeam = [JsonTeam]()
for index in 0...(team.getTeams().count - 1) {
let tempTeam = JsonTeam(id: team.getTeams()[index].getId(),
name: team.getTeams()[index].getName(),
member: team.getTeams()[index].getMembers())
print(team.getTeams()[index].getId())
print(team.getTeams()[index].getName())
print(team.getTeams()[index].getMembers())
tempArrayTeam.append(tempTeam)
}
completion(tempArrayTeam)
} catch let jsonErr{
print("Error serializing json: \(jsonErr.localizedDescription)")
}
}.resume()
}
func downloadTeamsImage(idTeam: Int,completion: @escaping (([JsonTeamImg]) -> Void)) {
//get teams with classes
let getTeamUrl = "http://127.0.0.1/MyWebService/api/fetch_image.php?id_team=\(idTeam)"
guard let urlTeam = URL(string: getTeamUrl) else { return }
URLSession.shared.dataTask(with: urlTeam) { (data,response,err) in
guard let data = data else {return}
do {
let team = try JSONDecoder().decode(ClassJsonTeamImage.self, from: data)
var tempArrayTeamImg = [JsonTeamImg]()
for index in 0...(team.getTeamsImg().count - 1) {
let tempTeamImg = JsonTeamImg(id: team.getTeamsImg()[index].getId(),
imagePath: team.getTeamsImg()[index].getImagePath(),
teamId: team.getTeamsImg()[index].getTeamId())
print(tempTeamImg.getId())
print(tempTeamImg.getImagePath())
print(tempTeamImg.getTeamId())
tempArrayTeamImg.append(tempTeamImg)
}
completion(tempArrayTeamImg)
} catch let jsonErr{
print("Error serializing json: \(jsonErr.localizedDescription)")
}
}.resume()
}
}
让我们切入正题：如果我单独调用这两个函数，它们当然可以工作，但我不知道如何将下载的数据合并到除此之外的 do-catch 中（例如在两个变量中，团队和在 teamsImg 中），以便我们可以贡献变量 teamsComplete 并在另一个视图控制器中传输数据。
提前致谢：D
【问题讨论】：
-
您已将所有数据设置在所需的变量中，您可以对这些数据做任何您想做的事情，并且可以在任何地方访问它们，您的问题是什么？
-
@RaziTiwana 问题是 datatask 在另一个线程上工作，因此，在 viewDidLoad 中，我应该在函数完成下载数据之前等待，然后才能对这些数据进行操作。事实上，应用程序在这条线上迷恋：for index2 in (0...(self.teamsImg!.count - 1)){ 错误是：线程 5：致命错误：在展开可选值时意外发现 nil
-
首先，它应该在那里崩溃，因为此时您的
self.teamsImg为零。其次，您应该在问题中提到这一点。现在您只需在完成中移动此代码。假设这是这里唯一的问题。 -
这里指的是操作依赖吗？比如，当您的数据从两个操作中准备好时，您想收到通知吗？
标签： swift xcode parsing url swift4