How use global Variables in views and classes? - swift

Question

I am trying through an external library to obtain the temperature of a device,
when the screen starts the temperature value is "----" when the device gives me the temperature result through a delegate I want to update the view with the value that is to save in the class (ts28bControllerDelegate) the value of the temperature and retrieve it in the view to show it, as I have my code always remains blank (Text ("\ (global.temp)"))
//
// TakeTemperatureTS28BUIView.swift
// aidicarev3UI
//
// Created by Laura Ramirez on 26/08/21.
//
import SwiftUI
struct ContentView2: View {
#State private var index = 1
#EnvironmentObject private var global: GlobalTs28b
init() {
Theme.navigationBarColors(background: .white , titleColor: UIColor( red: CGFloat(92/255.0), green: CGFloat(203/255.0), blue: CGFloat(207/255.0), alpha: CGFloat(1.0)))
}
var body: some View {
VStack{
ScrollView{
VStack{
VStack(){
Image("bluetooth-5")
.resizable()
.frame(width: UIScreen.main.bounds.width / 2, height: 140.0)
.padding()
Text("temp15Tittle")
.modifier(Fonts(fontName: .bold, size: 16))
.foregroundColor(Color("blueColor"))
.fixedSize(horizontal: false, vertical: true)
.padding(.top,30)
}
Divider()
.padding()
Text("temp1Tittle")
.frame(maxWidth: .infinity, alignment: .center)
.modifier(Fonts(fontName: .bold, size: 16))
.foregroundColor(Color("blackColor"))
.fixedSize(horizontal: false, vertical: true)
.padding(.top,10)
.padding()
HStack{
Text("\(global.temp)")
.autocapitalization(.none)
.foregroundColor(Color("blackColor"))
.padding(.leading,20)
Text("°C")
.modifier(Fonts(fontName: .bold, size: 16))
.foregroundColor(Color("blackColor"))
.padding()
}
.foregroundColor(Color("blackColor"))
.overlay(RoundedRectangle(cornerRadius: 40).stroke(Color("grayColor"), lineWidth: 1)).background(RoundedRectangle(cornerRadius: 40).fill(Color("whiteColor")))
.padding(.trailing,60)
.padding(.leading,60)
Button(action:{
SaveTemp()
}){
HStack{
Text("temp16Tittle")
.foregroundColor(Color("whiteColor"))
.modifier(Fonts(fontName: .bold, size: 16))
.frame(width: 150 , height: 10, alignment: .center)
}
.foregroundColor(Color("whiteColor"))
.modifier(Fonts(fontName: .medium, size: 16))
.padding()
.background(Color("blueColor"))
.cornerRadius(80)
.padding(.top,30)
}
}
}
.padding()
.padding()
Spacer()
MenuMain(index: self.$index)
}
.background(Color("backgroundColor"))
.navigationBarTitleDisplayMode(.inline)
.toolbar {
ToolbarItem(placement: .principal) {
VStack {
Text("temp7Tittle").font(.headline)
.modifier(Fonts(fontName: .light, size: 18))
.foregroundColor(Color("grayDarkColor"))
.fixedSize(horizontal: false, vertical: true)
.frame(maxWidth: .infinity, alignment: .leading)
}
}
}
.onAppear {
iHealthAuthTS28B()
}
.onDisappear {
//desconectar dispositivos
}
}
}
struct TakeTemperatureTS28BUIView_Previews: PreviewProvider {
static var previews: some View {
NavigationView{
TakeTemperatureTS28BUIView()
.navigationBarTitleDisplayMode(.inline)
.accentColor(.black)
.toolbar { // <2>
ToolbarItem(placement: .principal) { // <3>
HStack {
Text("temp7Tittle").font(.headline)
.modifier(Fonts(fontName: .light, size: 18))
.foregroundColor(Color("grayDarkColor"))
.fixedSize(horizontal: false, vertical: true)
.frame(maxWidth: .infinity, alignment: .leading)
Spacer()
}
}
}
}
}
}
struct TakeTemperatureTS28BUIView: View {
#StateObject private var global = GlobalTs28b()
var body: some View {
ContentView2()
.environmentObject(global)
}
}
func iHealthAuthTS28B() {
print("ENTRA EN AUTENTIFICACION DE IHEALTH TS28B")
let bundle = Bundle.main
let path = bundle.path(forResource: "com_aidicare_aidicarev3UI_ios", ofType: ".pem")
let cert = NSData(contentsOfFile: path!)
print(cert as Any)
let delegate = ts28bControllerDelegate.init()
IHSDKCloudUser.commandGetSDKUserInstance().commandSDKUserValidation(withLicense: cert as Data?, userDeviceAccess: {
devices in
print("--devices--")
print(devices as Any)
}, userValidationSuccess: { UserAuthenResult in
print("--UserAuthenResult--")
print(UserAuthenResult)
delegate.StartSync()
}, disposeErrorBlock: { UserAuthenResult in
print("--UserAuthenResult--")
print(UserAuthenResult)
switch (UserAuthenResult) {
case UserAuthen_InputError:
print("error")
break;
case UserAuthen_CertificateExpired:
print("certiificado expirado")
break;
case UserAuthen_InvalidCertificate:
print("certificado no valido")
break;
default:
break;
}
})
}
func Sincroniza(){
print("ENTRA EN TOMA DE TEMPERATURA TS28B")
iHealthAuthTS28B()
}
func SaveTemp(){
print("ENTRA EN GUARDAR DE TEMPERATURA")
let global = GlobalTs28b()
print("VALOR: ", global.temp)
}
class GlobalTs28b: ObservableObject {
#Published var temp: String = "----"
#Published var state: String = "----"
}
class ts28bControllerDelegate: NSObject, TS28BControllerDelegate {
var myCentralManager: CBCentralManager = CBCentralManager()
var controllerTS28B: TS28BController = TS28BController()
let user: HealthUser = HealthUser()
var device: TS28B = TS28B()
var connectedDevice: TS28B?
var global = GlobalTs28b()
override init() {
super.init()
print("ENTRA EN StartDiscoverTS28B")
controllerTS28B = TS28BController.shared()
controllerTS28B.delegate = self
}
func StartSync(){
print("empieza StartSync")
controllerTS28B.startScan()
}
// MARK: - delegate
public func controller(_ controller: TS28BController?, didDiscoverDevice device: TS28B?) {
print("The agent of the device is found")
connectedDevice = device
controller?.connectDevice(connectedDevice)
if let device = device {
print("DiscoverDevice: \(device)")
}
}
public func controller(_ controller: TS28BController?, didConnectSuccessDevice device: TS28B?) {
print("Successfully connected agent")
connectedDevice = device
if let device = device {
print("DiscoverDevice: \(device)")
}
}
public func controller(_ controller: TS28BController?, didConnectFailDevice device: TS28B?) {
print("Proxy failed to connect")
// self.recordTextView.text = #"连接失败";
}
public func controller(_ controller: TS28BController?, didDisconnectDevice device: TS28B?) {
print("Disconnected proxy")
// self.recordTextView.text = #"连接断开";
if let device = device {
print("DisConnectDevice: \(device) ")
}
}
public func controller(_ controller: TS28BController?, device: TS28B?, didUpdateTemperature value: Float, temperatureUnit unit: TemperatureUnit, measure date: Date?, measureLocation type: TemperatureType) {
print("Temperature UNIDAD:", unit)
print("Temperature:", value)
let valueFinal = ((value - 32) * 5/9)
let stringFloat = String(describing: valueFinal)
global.temp = stringFloat
print("centigadros:", global.temp)
}
}
can someone help me understand this?
thanks!

Answer 1

Regarding your (second) question in your comment,
here is some code that shows an approach to "send" a value from a
class (does not have to be a view) and receive that value in a View.
You could use this approach in your "ts28bControllerDelegate",
to send the temperature updates as they arrive in your ts28bControllerDelegate and
receive them in your views using .onReceive(...)
public func controller(_ controller: TS28BController?, device: TS28B?, didUpdateTemperature value: Float, temperatureUnit unit: TemperatureUnit, measure date: Date?, measureLocation type: TemperatureType) {
print("Temperature UNIDAD:", unit)
print("Temperature:", value)
let valueFinal = ((value - 32) * 5/9)
let stringFloat = String(valueFinal)
// send a message with the temp value
NotificationCenter.default.post(name: GlobalTs28b.globalMsg, object: stringFloat)
}
class GlobalTs28b: ObservableObject {
#Published var temp: String = "----"
#Published var state: String = "----"
// for testing, does not have to be in this class
static let globalMsg = Notification.Name("GlobalTs28b")
}
struct ContentView: View {
#StateObject var global = GlobalTs28b() // for testing
var body: some View {
NavigationView {
VStack (spacing: 55) {
NavigationLink("go to next view", destination: ViewTest2())
Text(global.temp).foregroundColor(.red)
}
.onReceive(NotificationCenter.default.publisher(for: GlobalTs28b.globalMsg)) { msg in
if let temp = msg.object as? String {
// update the StateObject with the new info, so the view will update
global.temp = temp
}
}
}.navigationViewStyle(.stack)
}
}
struct ViewTest2: View {
var body: some View {
VStack {
Button(action: {
// send a message to all listeners with the new temp,
// could be used in any class such as ts28bControllerDelegate
NotificationCenter.default.post(name: GlobalTs28b.globalMsg, object: "new temp")
}) {
Text("click to update temp")
}
}
}
}