Grouping json content - json

Question

This is my json:
[
{
"category" : {
"id" : 1,
"text" : "cat1"
},
"id" : 1,
"title" : "book1"
},{
"category" : {
"id" : 2,
"text" : "cat2"
},
"id" : 2,
"title" : "book2"
},{
"category" : {
"id" : 1,
"text" : "cat1"
},
"id" : 3,
"title" : "book3"
}
]
How can I grouping it by category? i want to use them in different collectionView
Thank you in advance

Answer 1

Define your JSON codable classes as follows.
typealias Result = [ResultElement]
struct ResultElement: Codable {
let category: Category
let id: Int
let title: String
}
struct Category: Codable {
let id: Int
let text: String
}
Now, Iterate Result array after JSON parsing using JSONDecoder and compare Category struct by equal operator and group it. Since Int and String inside Category struct conforms to Equatable protocol by default, Category struct can also be compared using Equatable protocol.

Answer 2

You can try
let str = """
[
{
"category" : {
"id" : 1,
"text" : "cat1"
},
"id" : 1,
"title" : "book1"
},{
"category" : {
"id" : 2,
"text" : "cat2"
},
"id" : 2,
"title" : "book2"
},{
"category" : {
"id" : 1,
"text" : "cat1"
},
"id" : 3,
"title" : "book3"
}
]
"""
do {
let res = try JSONDecoder().decode([Root].self, from: Data(str.utf8))
print(res)
let dic = Dictionary(grouping: res, by: { $0.category.text})
print(dic) // this dictionary is your new data source key is title of section value is sections rows
}
catch {
print(error)
}
struct Root: Codable {
let category: Category
let id: Int
let title: String
}
struct Category: Codable {
let id: Int
let text: String
}

Answer 3

Create Structs
//MARK: - MyData
public struct MyData {
public var category : Category
public var id : Int
public var title : String
}
//MARK: - Category
public struct Category {
public var id : Int
public var text : String
}
Create Model
func createData () -> [MyData] {
let c1 = Category.init(id: 1, text: "Cat1")
let d1 = MyData.init(category: c1, id: 1, title: "Book1")
let c2 = Category.init(id: 2, text: "Cat2")
let d2 = MyData.init(category: c2, id: 2, title: "Book2")
let c3 = Category.init(id: 1, text: "Cat1")
let d3 = MyData.init(category: c3, id: 3, title: "Book3")
return [d1, d2, d3]
}
Group your data
let ungroupedData = createData()
print("Ungrouped\n")
print(ungroupedData)
let groupedData = Dictionary(grouping: ungroupedData, by: {$0.category.text})
print("\nGrouped\n")
print(groupedData)
groupedData["Cat1"] // get cat1 array list