How to change the value of a var with a TextField SwiftUI - swift

Question

I was trying to make a weather api call, the api call needs to have a location. The location that I pass is a variable, but now I want to change the location value based on a TextField's input.
I made the apiKey shorter just for safety measures. There's more code, but it's not relevant.
I just need to know how to change the city variable that is on the WeatherClass using the TextField that is in the cityTextField View.
Thanks.
class WeatherClass: ObservableObject {
#Published var weatherAddress: String = ""
#Published var weatherDays: [WeatherDays] = []
var city: String = ""
func fetch() {
let location = city
let apiKey = "AP8LUYMSTHZ"
let url = URL(string: "https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/\(location)?key=\(apiKey)")!
URLSession.shared.dataTask(with: url) { data, response, error in
guard let data = data else { return }
if let weather = try? JSONDecoder().decode(WeatherData.self, from: data) {
DispatchQueue.main.async {
self.weatherAddress = weather.resolvedAddress
self.weatherDays = weather.days
}
} else {
print("City?")
}
}.resume()
}//----------------------------------- End of fetch()
}
struct WeatherData: Decodable {
let resolvedAddress: String
let days: [WeatherDays]
}
struct WeatherDays: Hashable, Decodable {
let datetime: String
let tempmax: Double
let tempmin: Double
let description: String
}
struct cityTextField: View {
#State var city: String = ""
var body: some View {
TextField("Search city", text: $city).frame(height:30).multilineTextAlignment(.center).background().cornerRadius(25).padding(.horizontal)
}
}
I already watched a lot of tutorials for similar things buts none of them really helped me.

Answer 1

Try this approach using minor modifications to
func fetch(_ city: String){...} to fetch the weather for the city in your
TextField using .onSubmit{...}
struct ContentView: View {
#StateObject var weatherModel = WeatherClass()
var body: some View {
VStack {
cityTextField(weatherModel: weatherModel)
}
}
}
struct cityTextField: View {
#ObservedObject var weatherModel: WeatherClass // <-- here
#State var city: String = ""
var body: some View {
TextField("Search city", text: $city)
.frame(height:30)
.multilineTextAlignment(.center)
.background()
.cornerRadius(25)
.padding(.horizontal)
.onSubmit {
weatherModel.fetch(city) // <-- here
}
}
}
class WeatherClass: ObservableObject {
#Published var weatherAddress: String = ""
#Published var weatherDays: [WeatherDays] = []
func fetch(_ city: String) { // <-- here
let apiKey = "AP8LUYMSTHZ"
// -- here
let url = URL(string: "https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/\(city)?key=\(apiKey)")!
URLSession.shared.dataTask(with: url) { data, response, error in
guard let data = data else { return }
if let weather = try? JSONDecoder().decode(WeatherData.self, from: data) {
DispatchQueue.main.async {
self.weatherAddress = weather.resolvedAddress
self.weatherDays = weather.days
}
} else {
print("City?")
}
}.resume()
}
}
Alternatively, as suggested by synapticloop, you could use this approach:
struct cityTextField: View {
#ObservedObject var weatherModel: WeatherClass // <-- here
var body: some View {
TextField("Search city", text: $weatherModel.city) // <-- here
.frame(height:30)
.multilineTextAlignment(.center)
.background()
.cornerRadius(25)
.padding(.horizontal)
.onSubmit {
weatherModel.fetch() // <-- here
}
}
}
class WeatherClass: ObservableObject {
#Published var weatherAddress: String = ""
#Published var weatherDays: [WeatherDays] = []
#Published var city: String = "" // <-- here
func fetch() {
let apiKey = "AP8LUYMSTHZ"
// -- here
let url = URL(string: "https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/\(city)?key=\(apiKey)")!
URLSession.shared.dataTask(with: url) { data, response, error in
guard let data = data else { return }
if let weather = try? JSONDecoder().decode(WeatherData.self, from: data) {
DispatchQueue.main.async {
self.weatherAddress = weather.resolvedAddress
self.weatherDays = weather.days
}
} else {
print("City?")
}
}.resume()
}
}