I try to decode json from api, for that i use this website : https://app.quicktype.io/
this is my json from api :
{
"id":"7d37091c-f214-491a-a50c-d289f0f7e255",
"uuid":"7d37091c-f214-491a-a50c-d289f0f7e255",
"brand":"Nike",
"breadcrumbs":[
],
"browseVerticals":[
"sneakers"
],
"category":"Nike Dunk",
"charityCondition":0,
"childId":null,
"colorway":"White/Black-Total Orange",
"condition":"New",
"countryOfManufacture":"VN",
"dataType":"product",
"description":"",
"hidden":false,
"listingType":"standard",
"minimumBid":25,
"gender":"men",
"doppelgangers":[
],
"media":{
"imageUrl":"https://images.stockx.com/images/Nike-Dunk-Low-Black-White-2021.jpg?fit=fill&bg=FFFFFF&w=700&h=500&auto=format,compress&trim=color&q=90&dpr=2&updated_at=1624941957",
"smallImageUrl":"https://images.stockx.com/images/Nike-Dunk-Low-Black-White-2021.jpg?fit=fill&bg=FFFFFF&w=300&h=214&auto=format,compress&trim=color&q=90&dpr=2&updated_at=1624941957",
"thumbUrl":"https://images.stockx.com/images/Nike-Dunk-Low-Black-White-2021.jpg?fit=fill&bg=FFFFFF&w=140&h=100&auto=format,compress&trim=color&q=90&dpr=2&updated_at=1624941957",
"gallery":[
],
"hidden":false
},
"name":"Black White (2021)",
"productCategory":"sneakers",
"releaseDate":"",
"releaseTime":0,
"belowRetail":false,
"retailPrice":110,
"shoe":"Nike Dunk High",
"shortDescription":"Nike-Dunk-Low-Black-White-2021",
"styleId":"DD1399-105",
"tickerSymbol":"NK-NIDLFDXWB",
"title":"Nike Dunk High Black White (2021)",
"traits":[
{
"name":"Style",
"value":"DD1399-105",
"filterable":true,
"visible":true,
"highlight":true
},
{
"name":"Colorway",
"value":"White/Black-Total Orange",
"filterable":true,
"visible":true,
"highlight":true
},
{
"name":"Retail Price",
"value":110,
"filterable":true,
"visible":true,
"highlight":false
},
{
"name":"Featured",
"value":false,
"filterable":false,
"visible":false,
"highlight":false
}
],
"type":0,
"urlKey":"nike-dunk-high-black-white-total-orange-2021",
"year":0,
"shoeSize":null,
"market":{
"productId":0,
"skuUuid":"",
"productUuid":"7d37091c-f214-491a-a50c-d289f0f7e255",
"lowestAsk":173,
"lowestAskSize":"15",
"parentLowestAsk":0,
"numberOfAsks":196,
"hasAsks":1,
"salesThisPeriod":69,
"salesLastPeriod":0,
"highestBid":220,
"highestBidSize":"9.5",
"numberOfBids":230,
"hasBids":1,
"annualHigh":297,
"annualLow":67,
"deadstockRangeLow":238,
"deadstockRangeHigh":274,
"volatility":0.070391,
"deadstockSold":5891,
"pricePremium":1.627,
"averageDeadstockPrice":175,
"lastSale":256,
"lastSaleSize":"10.5",
"salesLast72Hours":69,
"changeValue":51,
"changePercentage":0.249544,
"absChangePercentage":0.249544,
"totalDollars":1029494,
"lastLowestAskTime":1639141012,
"lastHighestBidTime":1639160362,
"lastSaleDate":"2021-12-11T00:55:16 00:00",
"createdAt":"2021-06-29T04:46:03 00:00",
"updatedAt":1639184839,
"deadstockSoldRank":37,
"pricePremiumRank":1,
"averageDeadstockPriceRank":42,
"featured":0
},
"_tags":[
"sneakers",
"nike",
"nike",
"dunk",
"style_id|dd1399-105",
"retail_price|110",
"colorway|white/black-total orange"
],
"lock_selling":false,
"selling_countries":[
"AD",
"AE",
],
"buying_countries":[
"AD",
"AE",
"ES",
"US",
"XK",
"IC",
"IN"
],
"objectID":"7d37091c-f214-491a-a50c-d289f0f7e255"
}
this is my Preview Provider :
class DeveloperPreview {
static let instance = DeveloperPreview()
init() { }
let sneaker = Sneakers(
id:"7d37091c-f214-491a-a50c-d289f0f7e255",
uuid:"7d37091c-f214-491a-a50c-d289f0f7e255",
brand:"Nike",
breadcrumbs:[
],
browseVerticals:[
"sneakers"
],
category:"Nike Dunk",
charityCondition:0,
childID: JSONNull(),
colorway:"White/Black-Total Orange",
condition:"New",
countryOfManufacture:"VN",
dataType:"product",
welcomeDescription: "welcom",
hidden:false,
listingType:"standard",
minimumBid:25,
gender:"men",
doppelgangers:[
],
media: Media(
imageURL:"https://images.stockx.com/images/Nike-Dunk-Low-Black-White-2021.jpg?fit=fill&bg=FFFFFF&w=700&h=500&auto=format,compress&trim=color&q=90&dpr=2&updated_at=1624941957",
smallImageURL:"https://images.stockx.com/images/Nike-Dunk-Low-Black-White-2021.jpg?fit=fill&bg=FFFFFF&w=300&h=214&auto=format,compress&trim=color&q=90&dpr=2&updated_at=1624941957",
thumbURL:"https://images.stockx.com/images/Nike-Dunk-Low-Black-White-2021.jpg?fit=fill&bg=FFFFFF&w=140&h=100&auto=format,compress&trim=color&q=90&dpr=2&updated_at=1624941957",
gallery:[
],
hidden:false
),
name:"Black White (2021)",
productCategory:"sneakers",
releaseDate:"",
releaseTime:0,
belowRetail:false,
retailPrice:110,
shoe:"Nike Dunk High",
shortDescription:"Nike-Dunk-Low-Black-White-2021",
styleID:"DD1399-105",
tickerSymbol:"NK-NIDLFDXWB",
title:"Nike Dunk High Black White (2021)",
traits: [traits],
type:0,
urlKey:"nike-dunk-high-black-white-total-orange-2021",
year:0,
shoeSize: JSONNull(),
market: Market(
productID:0,
skuUUID:"",
productUUID:"7d37091c-f214-491a-a50c-d289f0f7e255",
lowestAsk:173,
lowestAskSize:"15",
parentLowestAsk:0,
numberOfAsks:196,
hasAsks:1,
salesThisPeriod:69,
salesLastPeriod:0,
highestBid:220,
highestBidSize:"9.5",
numberOfBids:230,
hasBids:1,
annualHigh:297,
annualLow:67,
deadstockRangeLow:238,
deadstockRangeHigh:274,
volatility:0.070391,
deadstockSold:5891,
pricePremium:1.627,
averageDeadstockPrice:175,
lastSale:256,
lastSaleSize:"10.5",
salesLast72Hours:69,
changeValue:51,
changePercentage:0.249544,
absChangePercentage:0.249544,
totalDollars:1029494,
lastLowestAskTime:1639141012,
lastHighestBidTime:1639160362,
lastSaleDate:"2021-12-11T00:55:16 00:00",
createdAt:"2021-06-29T04:46:03 00:00",
updatedAt:1639184839,
deadstockSoldRank:37,
pricePremiumRank:1,
averageDeadstockPriceRank:42,
featured:0
),
tags:[
"sneakers",
"nike",
"nike",
"dunk",
"style_id|dd1399-105",
"retail_price|110",
"colorway|white/black-total orange"
],
lockSelling:false,
sellingCountries:[
"AD",
"AE",
"US",
"IN"
],
buyingCountries:[
"AD",
"AE",
"IN"
],
objectID:"7d37091c-f214-491a-a50c-d289f0f7e255"
)
let traits = Trait(
name:"Style",
value: .bool(true),
filterable:true,
visible:true,
highlight:true
)
and this is my decoder :
struct Trait: Codable {
let name: String
let value: Value
let filterable, visible, highlight: Bool
}
enum Value: Codable {
case bool(Bool)
case integer(Int)
case string(String)
init(from decoder: Decoder) throws {
let container = try decoder.singleValueContainer()
if let x = try? container.decode(Bool.self) {
self = .bool(x)
return
}
if let x = try? container.decode(Int.self) {
self = .integer(x)
return
}
if let x = try? container.decode(String.self) {
self = .string(x)
return
}
throw DecodingError.typeMismatch(Value.self, DecodingError.Context(codingPath: decoder.codingPath, debugDescription: "Wrong type for Value"))
}
func encode(to encoder: Encoder) throws {
var container = encoder.singleValueContainer()
switch self {
case .bool(let x):
try container.encode(x)
case .integer(let x):
try container.encode(x)
case .string(let x):
try container.encode(x)
}
}
}
My error come from the preview provider :
"Cannot use instance member 'traits' within property initializer; property initializers run before 'self' is available"
CodePudding user response：
The error is exactly pointed out by compiler. Converting from API response, this should work as expected on error snippet.
traits: [
Trait(
name:"Style",
value: .string("DD1399-105"),
filterable:true,
visible:true,
highlight:true
),
Trait(
name:"Colorway",
value: .string("White/Black-Total Orange"),
filterable:true,
visible:true,
highlight:true
),
Trait(
name:"Retail Price",
value: .integer(110),
filterable:true,
visible:true,
highlight:false
),
Trait(
name:"Featured",
value: .bool(false),
filterable:false,
visible:false,
highlight:false
)
],
CodePudding user response：
You cannot initialize properties which depend on each other on the top level of a class, you have to create the trait inside let sneaker = Sneakers( ...
Replace
traits: [traits],
with
traits: [Trait(
name:"Style",
value: .bool(true),
filterable:true,
visible:true,
highlight:true)],