Trying to access/modify SwiftUI variable from within a function - ios

Question

I am trying to get data from JSON. So far, I can extract it and print it.
My goal now is to be able to use it in my ContentView so that it can be used in a Text View or something similar. I have tried creating #State variables, passing it as a parameter, etc. etc. and nothing seems to work.
I'm fairly new to SwiftUI, so I appreciate the help!
struct GeoService: Codable {
var status: String
var results: [GeoResult]
}
struct GeoResult: Codable {
struct Geometry: Codable {
struct Location: Codable {
let lat: Float
let lng: Float
init() {
lat = 32
lng = 30
}
}
let location: Location
}
let formatted_address: String
let geometry: Geometry
}
struct ContentView: View {
// #State private var results: Any ?????????
var body: some View {
NavigationView {
Text("Test")
.navigationTitle("Quotes")
.task {
await handleData()
}
}
}
func handleData() async {
let geoResult="""
{
"results": [
{
"formatted_address": "1600 Amphitheatre Parkway, Mountain View, CA 94043, USA",
"geometry": {
"location": {
"lat": 37.4224764,
"lng": -122.0842499
}
}
},
{
"formatted_address": "Test addresss",
"geometry": {
"location": {
"lat": 120.32132145,
"lng": -43.90235469
}
}
}
],
"status": "OK"
}
""".data(using: .utf8)!
let decoder = JSONDecoder()
print("executing handleData()")
do {
let obj = try decoder.decode(GeoService.self, from: geoResult)
for result in obj.results {
print("Address: \(result.formatted_address)")
print("Lat/long: (\(result.geometry.location.lat), \(result.geometry.location.lng))")
}
} catch {
print("Did not work :(")
}
}
}

Answer 1

I moved the get request to its own class so we can leverage ObservableObject and Publish the data. Publishing the data allows the subscribing views to update data when the published data changes. In this case, your ContentView is subscribing to the data via the #ObservedObject var geoData: ResponseData line of code.
Additionally, I added how to access two pieces of relevant data in your view, and displayed it in a list for easy reading. This should give you an idea of how to access/display the data.
Hopefully this provides enough information for you to tweak the answer to get it work the way you desire.
import SwiftUI
struct GeoService: Codable {
var status: String?
var results: [GeoResult]?
}
struct GeoResult: Codable {
struct Geometry: Codable {
struct Location: Codable {
let lat: Float
let lng: Float
init() {
lat = 32
lng = 30
}
}
let location: Location
}
let formatted_address: String
let geometry: Geometry
}
struct ContentView: View {
#ObservedObject var geoData: ResponseData
var body: some View {
NavigationView {
if #available(iOS 15.0, *) {
List {
Text(geoData.geoResultsData?.results?[0].formatted_address ?? "Loading")
Text(String(geoData.geoResultsData?.results?[0].geometry.location.lat ?? 0))
}
.navigationTitle("Quotes")
.task {
await geoData.handleData()
print(geoData.geoResultsData, "yessssss")
}
} else {
Text("failure")
}
}
}
}
class ResponseData: ObservableObject {
#Published var geoResultsData: GeoService?
func handleData() async {
let geoResult="""
{
"results": [
{
"formatted_address": "1600 Amphitheatre Parkway, Mountain View, CA 94043, USA",
"geometry": {
"location": {
"lat": 37.4224764,
"lng": -122.0842499
}
}
},
{
"formatted_address": "Test addresss",
"geometry": {
"location": {
"lat": 120.32132145,
"lng": -43.90235469
}
}
}
],
"status": "OK"
}
""".data(using: .utf8)!
let decoder = JSONDecoder()
print("executing handleData()")
do {
let obj = try decoder.decode(GeoService.self, from: geoResult)
geoResultsData = obj
} catch {
print("Did not work :(")
}
}
}
EDIT:
You will need to initialize some data within your app. You can initialize it as empty for the time being, if desired. This can be done by doing something like the following: ContentView(geoData: ResponseData.init())