我在swiftui中有一个选择器,我需要从我当前托管在Mac上的json中填充它。
当我运行代码时,显示的选取器保持为空,但数据可用(如果我单击下面的按钮来打印它(。
这是我的代码:
选取器 (ContentView.swift(:
@State var nwm = NetworkManager()
...
Picker("Wähle deine Schule", selection: $selectedSchool) {
ForEach(0 ..< nwm.schoolList.results.count) {
Text(self.nwm.schoolList.results[$0].name).tag($0)
}
}.labelsHidden()
网络管理器.swift:
class NetworkManager : ObservableObject {
var didChange = PassthroughSubject<NetworkManager, Never>()
var schoolList = SchoolList(results: []) {
didSet {
didChange.send(self)
}
}
init() {
guard let url = URL(string: "http://jonasmacbookpro.local:8083/IOSApp/getDKSchools") else { return }
URLSession.shared.dataTask(with: url) {
(data, _, _) in
let schoolList = try! JSONDecoder().decode(SchoolList.self, from: data!)
DispatchQueue.main.async {
self.schoolList = schoolList
}
}.resume()
}
}
学校.swift
struct School : Identifiable, Decodable {
let id = UUID()
var name : String
var ort : String
var link : String
}
struct SchoolList: Decodable {
var results: [School]
}
有谁知道,为什么它不起作用?
而不是
@State var nwm = NetworkManager((
用
@ObservedObject var nwm = NetworkManager()
而不是
var didChange = PassthroughSubject<NetworkManager, Never>() var schoolList = SchoolList(results: []) { didSet { didChange.send(self) } }
用途
@Published var schoolList = SchoolList(results: [])
若要刷新选取器,需要添加一个唯一的 ID。您可以将.id(UUID())
添加到您的选择器中,它应该可以正常工作