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@azamsharp
Created Jun 30, 2022
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//
// ContentView.swift
// Learn
//
// Created by Mohammad Azam on 6/29/22.
//
import SwiftUI
class AppState: ObservableObject {
@Published var value: Int = 0
@Published var isAuthenticated: Bool = false
var counterState = CounterState()
var authState = AuthState()
}
class CounterState: ObservableObject {
@Published var value: Int = 0
}
class AuthState: ObservableObject {
@Published var isAuthenticated: Bool = false
}
protocol IncrementCounterViewModelProtocol {
func increment()
}
protocol DisplayCounterViewModelProtocol {
var counter: Int { get }
}
class IncrementCounterViewModel: IncrementCounterViewModelProtocol {
var appState: AppState
init(appState: AppState) {
self.appState = appState
}
func increment() {
appState.value += 1
}
}
class DisplayCounterViewModel: DisplayCounterViewModelProtocol {
private var appState: AppState
init(appState: AppState) {
self.appState = appState
}
var counter: Int {
appState.value
}
}
struct DisplayCounterView: View {
let vm: DisplayCounterViewModelProtocol
init(vm: any DisplayCounterViewModelProtocol) {
self.vm = vm
}
var body: some View {
let _ = Self._printChanges()
Text("\(vm.counter)")
}
}
struct IncrementCounterView: View {
let vm: IncrementCounterViewModelProtocol
init(vm: any IncrementCounterViewModelProtocol) {
self.vm = vm
}
var body: some View {
let _ = Self._printChanges()
VStack {
Button("Increment") {
vm.increment()
}
}
}
}
struct FancyCounterView: View {
let counter: Int
var body: some View {
Text("\(counter)")
}
}
struct FancyView: View {
let vm: FancyViewModel
var body: some View {
FancyCounterView(counter: vm.counter)
}
}
class FancyViewModel {
private var appState: AppState
init(appState: AppState) {
self.appState = appState
}
var counter: Int {
self.appState.value
}
}
struct GrandChildView: View {
@EnvironmentObject var counterState: CounterState
var body: some View {
let _ = Self._printChanges()
VStack {
Text("GRAND CHILD VIEW")
Text("\(counterState.value)")
}
}
}
struct ChildView: View {
var body: some View {
GrandChildView()
}
}
struct ParentView: View {
var body: some View {
ChildView()
}
}
struct AuthView: View {
@EnvironmentObject var authState: AuthState
var body: some View {
VStack {
Text(authState.isAuthenticated ? "AUTHENTICATED": "NOT AUTHENTICATED")
Button("Toggle Auth") {
authState.isAuthenticated.toggle()
}
}
}
}
struct ContentView: View {
@EnvironmentObject var appState: AppState
var body: some View {
let _ = Self._printChanges()
VStack {
DisplayCounterView(vm: DisplayCounterViewModel(appState: appState))
IncrementCounterView(vm: IncrementCounterViewModel(appState: appState))
ParentView()
AuthView()
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView().environmentObject(AppState())
}
}
//
// LearnApp.swift
// Learn
//
// Created by Mohammad Azam on 6/29/22.
//
import SwiftUI
@main
struct LearnApp: App {
let appState = AppState()
var body: some Scene {
WindowGroup {
ContentView()
.environmentObject(appState)
.environmentObject(appState.counterState)
.environmentObject(appState.authState)
}
}
}
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