SwiftUI: Group data by name and display in expanded list

Question

I tried to group the data get from API and display it in a expanding list like How to create expanding lists – SwiftUI Here is some sample data .

[
    {
        "name": "Hair Cut",
        "createDate": 1600423060,
        "voucherID": 12311,
        "type": "service",
        "expiryDate": 1600682257,
        "trxnID": 2683125
    },
    {
        "name": "Hair Cut",
        "createDate": 1600423060,
        "voucherID": 31231,
        "type": "service",
        "expiryDate": 1600682257,
        "trxnID": 2683124
    },
    {
        "name": "Package B",
        "createDate": 1596217117,
        "voucherID": 12312,
        "type": "service",
        "expiryDate": 0,
        "trxnID": 2423309
    }
]

Now I already group the data by using the dictionary Dictionary(grouping: self.vouchers, by: {$0.name!}) into @Published var gVouchers = Dictionary<String, Any>() . So the problem now is how I display them in a expanding list. The expanding list use a children which I don't have in dictionary. So is there any method to do so? Or I cannot use the dictionary to do the grouping?

Does this answer your question: https://stackoverflow.com/a/61441076/12299030? — Asperi, Sep 22 '20 at 03:40
@Asperi for values of my dictionary will be an array. So I have no idea how to do. I tried `List(Array(vouchers.gVouchers.keys), id:\.self){key in Text(key)` It can display the key but not the values. — SAS231, Sep 22 '20 at 03:56
https://docs.swift.org/swift-book/LanguageGuide/CollectionTypes.html — Asperi, Sep 22 '20 at 03:58

score 0 · Accepted Answer · answered Sep 22 '20 at 07:12

I have followed the tutorial(YouTube link), can you please try below code?(as I'm unable to check the as I haven't upgraded the Xcode). In below code, I'm just parsing the JSON file stored locally with your data.

struct ListItem: Decodable, Identifiable {
    let id = UUID()
    var name: String
    var createDate: TimeInterval?
    var voucherID: Int?
    var type: String?
    var expiryDate: TimeInterval?
    var trxnID: Int?
    var items: [ListItem]?
    
    init(name: String, items: [ListItem]) {
        self.name = name
        self.items = items
    }
}

struct ContentView: View {
    @State private var items: [ListItem] = []
    
    var body: some View {
        List(items, children: \.items) { item in
            Text(item.name)
        }.onAppear {
            self.parseJSON()
        }
    }
    
    func parseJSON() {
        guard let filePath = Bundle.main.url(forResource: "demo", withExtension: "json") else {
            items = []
            return
        }
        
        do {
            let data = try Data(contentsOf: filePath)
            let results = try JSONDecoder().decode([ListItem].self, from: data)
            let dict = Dictionary(grouping: results, by: { $0.name })
            self.items = dict.map { (key, value) -> ListItem in
                ListItem(name: key, items: value)
            }
        } catch {
            print(error)
        }
    }
}

SwiftUI: Group data by name and display in expanded list

1 Answers1