我目前正在从Tracker Network Apex Legends Api获取数据。我在使用...时遇到了一个问题...
self.title2 = json.data.children.map{$0.stats[1].metadata.name}
将引发错误。据我所知，这是由于某些“孩子”没有价值。
简单地说，我想知道如何使用上面的代码，并用字符串（例如数组中的“ 0”或“ nil”）替换任何空值或不存在的值？
我将这些值放入数组中，然后在表格视图中显示它们。
由于每个实例都有值，因此以下方法可以很好地工作。
self.title2 = json.data.children.map{$0.stats[0].metadata.name}
这是我正在使用的以下代码。
import Foundation
struct Store: Codable {
let data: DataClass
enum CodingKeys: String, CodingKey {
case data = "data"
}
}
struct DataClass: Codable {
let id: String
let type: String
let children: [Child]
let metadata: DataMetadata
let stats: [Stat]
enum CodingKeys: String, CodingKey {
case id = "id"
case type = "type"
case children = "children"
case metadata = "metadata"
case stats = "stats"
}
}
struct Child: Codable {
let id: String
let type: String
let metadata: ChildMetadata
let stats: [Stat]
enum CodingKeys: String, CodingKey {
case id = "id"
case type = "type"
case metadata = "metadata"
case stats = "stats"
}
}
struct ChildMetadata: Codable {
let legendName: String
let icon: String
let bgimage: String
enum CodingKeys: String, CodingKey {
case legendName = "legend_name"
case icon = "icon"
case bgimage = "bgimage"
}
}
struct Stat: Codable {
let metadata: StatMetadata
let value: Int
let percentile: Double?
let rank: Int?
let displayValue: String
let displayRank: String
enum CodingKeys: String, CodingKey {
case metadata = "metadata"
case value = "value"
case percentile = "percentile"
case rank = "rank"
case displayValue = "displayValue"
case displayRank = "displayRank"
}
}
struct StatMetadata: Codable {
let key: String
let name: String
let categoryKey: StatsCategoryOrder
let categoryName: CategoryName
let isReversed: Bool
enum CodingKeys: String, CodingKey {
case key = "key"
case name = "name"
case categoryKey = "categoryKey"
case categoryName = "categoryName"
case isReversed = "isReversed"
}
}
enum StatsCategoryOrder: String, Codable {
case combat = "combat"
case game = "game"
case weapons = "weapons"
}
enum CategoryName: String, Codable {
case combat = "Combat"
case game = "Game"
case weapons = "Weapons"
}
struct DataMetadata: Codable {
let statsCategoryOrder: [StatsCategoryOrder]
let platformID: Int
let platformUserHandle: String
let accountID: String
let cacheExpireDate: String
let level: Int
enum CodingKeys: String, CodingKey {
case statsCategoryOrder = "statsCategoryOrder"
case platformID = "platformId"
case platformUserHandle = "platformUserHandle"
case accountID = "accountId"
case cacheExpireDate = "cacheExpireDate"
case level = "level"
}
}
用于获取json数据并放入数组。
//images
var legendImgArr = [""]
//legend name
var legendTitle = [""]
//data set 1
var title1 = [""]
var data1 = [0]
//data set 2
var title2 = [""]
var data2 = [0]
//data set 3
var title3 = ["nil"]
var data3 = [0]
加载到UITableView中。
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell1", for: indexPath) as! statsOutlets
//loading Legend Images
let request = NSURLRequest(url: NSURL(string: legendImgArr[indexPath.row])! as URL)
URLSession.shared.dataTask(with: request as URLRequest) { (data, response, error) -> Void in
if error != nil {
print("Failed to load image for url: \(self.legendImgArr), error: ")
return
}
guard let httpResponse = response as? HTTPURLResponse else {
print("Not an NSHTTPURLResponse from loading url: \(self.legendImgArr)")
return
}
if httpResponse.statusCode != 200 {
print("Bad response statusCode: \(httpResponse.statusCode) while loading url: \(self.legendImgArr)")
return
}
DispatchQueue.main.asyncAfter(deadline: .now() ) { () -> Void in
cell.legendImage.image = UIImage(data: data!)
}
}.resume()
//loading labels
cell.legendName.text = legendTitle[indexPath.row]
cell.stat1Title.text = title1[indexPath.row]
cell.stat1Data.text = String(data1[indexPath.row])
cell.stat2Title.text = title2[indexPath.row]
cell.stat2Data.text = String(data2[indexPath.row])
cell.stat3Title.text = title3[indexPath.row]
cell.stat3Data.text = String(data3[indexPath.row])
return cell
}
获取Json数据。
let formattedName = usernameEntry.text!.replacingOccurrences(of: " ", with: "%20")
let PlayerStatURL = URL(string: "https://public-api.tracker.gg/apex/v1/standard/profile/\(selectedPlatform)/\(formattedName)")
if let unwrappedURL = PlayerStatURL {
var request = URLRequest(url: unwrappedURL)
request.addValue("my-api-key", forHTTPHeaderField: "TRN-Api-Key")
let dataTask = URLSession.shared.dataTask(with: request) { (data, response, error) in
// you should put in error handling code, too
if let data = data {
do {
let json = try JSONDecoder().decode(Store.self, from: data) as Store
// print(json.data)
//account level
print("Level: \(json.data.metadata.level)")
//images
self.legendImgArr = json.data.children.map{$0.metadata.icon}
//titles
self.legendTitle = json.data.children.map{$0.metadata.legendName}
//label 1 (this label works fine due to there being values for all 'legendName')
self.title1 = json.data.children.map{$0.stats[0].metadata.name}
self.data1 = json.data.children.map{$0.stats[0].value}
//!!!Error happens here (I think this is because there are null values or nothing at all for some of them)!!!
self.title2 = json.data.children.map{$0.stats[1].metadata.name}
self.data2 = json.data.children.map{$0.stats[1].value}
self.title3 = json.data.children.map{$0.stats[2].metadata.name}
self.data3 = json.data.children.map{$0.stats[2].value}
} catch {
print(error.localizedDescription)
}
DispatchQueue.main.asyncAfter(deadline: .now() ) {
self.tableView.reloadData()
self.viewDidLoad()
self.statusOfLoad.stopAnimating()
self.statusOfLoad.isHidden = true
}
}
}
dataTask.resume()
}
}
我已将错误发生在上面的地方。 还知道这可行...
self.title2 = json.data.children[0].stats[1].metadata.name
但这不起作用
self.title2 = json.data.children.map{$0.stats[1].metadata.name}
这是有效代码的输出。
self.title1 = json.data.children.map{$0.stats[0].metadata.name}
输出：
["Kills", "Kills", "Kills", "Kills", "Kills", "Kills", "Kills", "Kills"]
这是无效代码的输出。
self.title2 = json.data.children.map{$0.stats[1].metadata.name}
输出：
Fatal error: Index out of range
Json，通过邮递员解析时。
{
"data": {
"id": "b2553208-d89f-4b5d-b08d-5b61dc8d68fe",
"type": "player",
"children": [
{
"id": "legend_8",
"type": "",
"metadata": {
"legend_name": "Pathfinder",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-pathfinder.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/pathfinder-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 102,
"percentile": 17,
"rank": 8469,
"displayValue": "102",
"displayRank": "8,469"
},
{
"metadata": {
"key": "Damage",
"name": "Damage",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 28845,
"percentile": 8,
"rank": 3455,
"displayValue": "28,845",
"displayRank": "3,455"
},
{
"metadata": {
"key": "Headshots",
"name": "Headshots",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 163,
"percentile": 2.8,
"rank": 1363,
"displayValue": "163",
"displayRank": "1,363"
}
]
},
{
"id": "legend_6",
"type": "",
"metadata": {
"legend_name": "Gibraltar",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-gibraltar.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/gibraltar-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 1,
"percentile": 76,
"rank": 12420,
"displayValue": "1",
"displayRank": "12,420"
},
{
"metadata": {
"key": "Finishers",
"name": "Finishers",
"categoryKey": "game",
"categoryName": "Game",
"isReversed": false
},
"value": 0,
"rank": 256,
"displayValue": "0",
"displayRank": "256"
}
]
},
{
"id": "legend_2",
"type": "",
"metadata": {
"legend_name": "Bangalore",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-bangalore.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/bangalore-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 16,
"percentile": 76,
"displayValue": "16",
"displayRank": ""
},
{
"metadata": {
"key": "Headshots",
"name": "Headshots",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 22,
"percentile": 100,
"rank": 14576,
"displayValue": "22",
"displayRank": "14,576"
},
{
"metadata": {
"key": "Specific2",
"name": "Legend Specific 2",
"categoryKey": "game",
"categoryName": "Game",
"isReversed": false
},
"value": 3,
"percentile": 100,
"rank": 2392,
"displayValue": "3",
"displayRank": "2,392"
}
]
},
{
"id": "legend_5",
"type": "",
"metadata": {
"legend_name": "Bloodhound",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-bloodhound.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/bloodhound-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 6,
"percentile": 83,
"displayValue": "6",
"displayRank": ""
},
{
"metadata": {
"key": "Specific2",
"name": "Legend Specific 2",
"categoryKey": "game",
"categoryName": "Game",
"isReversed": false
},
"value": 4,
"percentile": 100,
"rank": 4007,
"displayValue": "4",
"displayRank": "4,007"
}
]
},
{
"id": "legend_1",
"type": "",
"metadata": {
"legend_name": "Wraith",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-wraith.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/wraith-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 7,
"percentile": 87,
"displayValue": "7",
"displayRank": ""
},
{
"metadata": {
"key": "ArKills",
"name": "AR Kills",
"categoryKey": "weapons",
"categoryName": "Weapons",
"isReversed": false
},
"value": 0,
"rank": 1478,
"displayValue": "0",
"displayRank": "1,478"
}
]
},
{
"id": "legend_4",
"type": "",
"metadata": {
"legend_name": "Mirage",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-mirage.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/mirage-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 8,
"percentile": 84,
"rank": 33915,
"displayValue": "8",
"displayRank": "33,915"
},
{
"metadata": {
"key": "Damage",
"name": "Damage",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 3106,
"percentile": 27,
"rank": 11370,
"displayValue": "3,106",
"displayRank": "11,370"
},
{
"metadata": {
"key": "Headshots",
"name": "Headshots",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 13,
"percentile": 100,
"rank": 5099,
"displayValue": "13",
"displayRank": "5,099"
}
]
},
{
"id": "legend_3",
"type": "",
"metadata": {
"legend_name": "Caustic",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-caustic.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/caustic-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 5,
"percentile": 72,
"rank": 10472,
"displayValue": "5",
"displayRank": "10,472"
},
{
"metadata": {
"key": "Damage",
"name": "Damage",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 2104,
"percentile": 13,
"rank": 2126,
"displayValue": "2,104",
"displayRank": "2,126"
},
{
"metadata": {
"key": "Headshots",
"name": "Headshots",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 10,
"percentile": 4,
"rank": 854,
"displayValue": "10",
"displayRank": "854"
}
]
},
{
"id": "legend_7",
"type": "",
"metadata": {
"legend_name": "Lifeline",
"icon": "https://media.contentapi.ea.com/content/dam/apex-legends/images/2019/01/legends-character-tiles/apex-grid-tile-legends-lifeline.png.adapt.crop16x9.png",
"bgimage": "https://trackercdn.com/cdn/apex.tracker.gg/legends/lifeline-concept-bg-small.jpg"
},
"stats": [
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 12,
"percentile": 76,
"displayValue": "12",
"displayRank": ""
}
]
}
],
"metadata": {
"statsCategoryOrder": [
"combat",
"game",
"weapons"
],
"platformId": 5,
"platformUserHandle": "ItsSpress",
"accountId": "b2553208-d89f-4b5d-b08d-5b61dc8d68fe",
"cacheExpireDate": "3/2/2019 9:11:33 AM",
"level": 32
},
"stats": [
{
"metadata": {
"key": "Level",
"name": "Level",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 32,
"percentile": 57,
"displayValue": "32",
"displayRank": ""
},
{
"metadata": {
"key": "Kills",
"name": "Kills",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 157,
"percentile": 50,
"displayValue": "157",
"displayRank": ""
},
{
"metadata": {
"key": "Damage",
"name": "Damage",
"categoryKey": "combat",
"categoryName": "Combat",
"isReversed": false
},
"value": 34055,
"percentile": 36,
"displayValue": "34,055",
"displayRank": ""
},
{
"metadata": {
"key": "Finishers",
"name": "Finishers",
"categoryKey": "game",
"categoryName": "Game",
"isReversed": false
},
"value": 0,
"displayValue": "0",
"displayRank": ""
},
{
"metadata": {
"key": "ArKills",
"name": "AR Kills",
"categoryKey": "weapons",
"categoryName": "Weapons",
"isReversed": false
},
"value": 0,
"displayValue": "0",
"displayRank": ""
}
]
}
}
如果我做这样的事情...
print(json.data.children.map{$0.stats.map{$0.metadata.name}})
我知道...
[["Kills", "Damage", "Headshots"], ["Kills", "Finishers"], ["Kills", "Headshots", "Legend Specific 2"], ["Kills", "Legend Specific 2"], ["Kills", "AR Kills"], ["Kills", "Damage", "Headshots"], ["Kills", "Damage", "Headshots"], ["Kills"]]
答案 0 :(得分：1)
问题是自白的。
您正在将组织良好的结构拆分为单独的数组。 不要那样做。永远不会。
保持结构层次结构并从结构中获取值。
似乎children数组代表数据源数组，因此删除
drop index (select indexname from pg_indexes where tablename in ('t1','t2'/*list of tables of which index I want to drop*/) ;
并声明一个数组
var legendImgArr = [""]
//legend name
var legendTitle = [""]
//data set 1
var title1 = [""]
var data1 = [0]
//data set 2
var title2 = [""]
var data2 = [0]
//data set 3
var title3 = ["nil"]
var data3 = [0]
并在解码JSON后分配var children = [Child]()
数组
[Child]还删除所有为这些已删除数组分配值的行。
为方便起见，创建一个辅助函数以从self.children = json.data.children
中提取给定索引的数据：
stats然后在func nameValue(for stats: [Stat], at index : Int) -> (String, String) {
guard index < stats.count else { return ("", "") }
let stat = stats[index]
return (stat.metadata.name, String(stat.value))
}
中将孩子带到索引路径一次
cellforRow，然后将值分配给标签
let child = children[indexPath.row]
这比不可控制的可怕单独阵列 更加有效和安全。