我正在用SwiftUI开发一个具有两个视图的简单iOS应用：LogInView()和HomeView()。
我想要的东西非常简单：当用户单击LogInView()上的登录按钮时，我希望该应用隐藏LogInView()并显示{{1} }，全屏显示，不，就像模式，并且不允许用户返回。
这可以通过Swift和UIKit中的Storyboards轻松完成，有什么方法可以通过SwiftUI做到吗？
感谢您的帮助。 预先感谢。
我的代码：
LogInView ：
HomeView()HomeView ：
struct LogInView: View {
var body: some View {
VStack {
Text("Welcome to Mamoot!")
.font(.largeTitle)
.fontWeight(.heavy)
Text("We are glad to have you here.")
Text("Please log in with your Mastodon or Twitter account to continue.")
.multilineTextAlignment(.center)
.lineLimit(4)
.padding()
Spacer()
FloatingTextField(title: "Username", placeholder: "Username", width: 300, type: "Username")
FloatingTextField(title: "Password", placeholder: "Password", width: 300, type: "password")
.padding(.top, -50)
Spacer()
ZStack {
Button(action: { /* go to HomeView() */ }) {
Text("Log in")
.foregroundColor(Color.white)
.bold()
.shadow(color: .red, radius: 10)
}
.padding(.leading, 140)
.padding(.trailing, 140)
.padding(.top, 15)
.padding(.bottom, 15)
.background(Color.red)
.cornerRadius(10)
}
.padding(.bottom)
}
}
}
答案 0 :(得分：5)
更新：我花了一些时间来更新答案并添加过渡。请注意，我更改了“按VStack分组”，否则过渡无效。
您可以更改withAnimation通话中的持续时间（按钮关闭）。
我还在按钮中移动了一些修饰符，因此整个过程都是“可插拔的”。否则，仅点击按钮上的文字将触发操作。
您可以使用ObservedObject，EnvironmentObject或Binding。这是ObservedObject的示例：
import SwiftUI
class Model: ObservableObject {
@Published var loggedIn = false
}
struct ContentView: View {
@ObservedObject var model = Model()
var body: some View {
VStack {
if model.loggedIn {
HomeView().transition(.opacity)
} else {
LogInView(model: model).transition(.opacity)
}
}
}
}
struct HomeView: View {
var body: some View {
Text("Home Page")
}
}
struct LogInView: View {
@ObservedObject var model: Model
var body: some View {
VStack {
Text("Welcome to Mamoot!")
.font(.largeTitle)
.fontWeight(.heavy)
Text("We are glad to have you here.")
Text("Please log in with your Mastodon or Twitter account to continue.")
.multilineTextAlignment(.center)
.lineLimit(4)
.padding()
Spacer()
// FloatingTextField(title: "Username", placeholder: "Username", width: 300, type: "Username")
// FloatingTextField(title: "Password", placeholder: "Password", width: 300, type: "password")
// .padding(.top, -50)
Spacer()
ZStack {
Button(action: {
withAnimation(.easeInOut(duration: 1.0)) {
self.model.loggedIn = true
}
}) {
Text("Log in")
.foregroundColor(Color.white)
.bold()
.shadow(color: .red, radius: 10)
// moved modifiers here, so the whole button is tappable
.padding(.leading, 140)
.padding(.trailing, 140)
.padding(.top, 15)
.padding(.bottom, 15)
.background(Color.red)
.cornerRadius(10)
}
}
.padding(.bottom)
}
}
}
答案 1 :(得分：1)
@kontiki的回答可能是最SwiftUI-y，但是我将提出一个不同的解决方案，可能不那么好！但也许更灵活/可扩展。
您可以交换rootView of UIHostingController：
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
var window: UIWindow?
fileprivate lazy var appCoordinator: AppCoordinator = {
let rootViewController: UIHostingController<AnyView> = .init(rootView: EmptyView().eraseToAny())
window?.rootViewController = rootViewController
let navigationHandler: (AnyScreen, TransitionAnimation) -> Void = { [unowned rootViewController, window] (newRootScreen: AnyScreen, transitionAnimation: TransitionAnimation) in
UIView.transition(
with: window!,
duration: 0.5,
options: transitionAnimation.asUIKitTransitionAnimation,
animations: { rootViewController.rootView = newRootScreen },
completion: nil
)
}
return AppCoordinator(
dependencies: (
securePersistence: KeyValueStore(KeychainSwift()),
preferences: .default
),
navigator: navigationHandler
)
}()
func scene(
_ scene: UIScene,
willConnectTo session: UISceneSession,
options connectionOptions: UIScene.ConnectionOptions
) {
self.window = .fromScene(scene)
appCoordinator.start()
}
}
enum TransitionAnimation {
case flipFromLeft
case flipFromRight
}
private extension TransitionAnimation {
var asUIKitTransitionAnimation: UIView.AnimationOptions {
switch self {
case .flipFromLeft: return UIView.AnimationOptions.transitionFlipFromLeft
case .flipFromRight: return UIView.AnimationOptions.transitionFlipFromRight
}
}
}
final class AppCoordinator {
private let preferences: Preferences
private let securePersistence: SecurePersistence
private let navigationHandler: (AnyScreen, TransitionAnimation) -> Void
init(
dependencies: (securePersistence: SecurePersistence, preferences: Preferences),
navigator navigationHandler: @escaping (AnyScreen, TransitionAnimation) -> Void
) {
self.preferences = dependencies.preferences
self.securePersistence = dependencies.securePersistence
self.navigationHandler = navigationHandler
}
}
// MARK: Internal
internal extension AppCoordinator {
func start() {
navigate(to: initialDestination)
}
}
// MARK: Destination
private extension AppCoordinator {
enum Destination {
case welcome, getStarted, main
}
func navigate(to destination: Destination, transitionAnimation: TransitionAnimation = .flipFromLeft) {
let screen = screenForDestination(destination)
navigationHandler(screen, transitionAnimation)
}
func screenForDestination(_ destination: Destination) -> AnyScreen {
switch destination {
case .welcome: return AnyScreen(welcome)
case .getStarted: return AnyScreen(getStarted)
case .main: return AnyScreen(main)
}
}
var initialDestination: Destination {
guard preferences.hasAgreedToTermsAndPolicy else {
return .welcome
}
guard securePersistence.isAccountSetup else {
return .getStarted
}
return .main
}
}
// MARK: - Screens
private extension AppCoordinator {
var welcome: some Screen {
WelcomeScreen()
.environmentObject(
WelcomeViewModel(
preferences: preferences,
termsHaveBeenAccepted: { [unowned self] in self.start() }
)
)
}
var getStarted: some Screen {
GetStartedScreen()
.environmentObject(
GetStartedViewModel(
preferences: preferences,
securePersistence: securePersistence,
walletCreated: { [unowned self] in self.navigate(to: .main) }
)
)
}
var main: some Screen {
return MainScreen().environmentObject(
MainViewModel(
preferences: preferences,
securePersistence: securePersistence,
walletDeleted: { [unowned self] in
self.navigate(to: .getStarted, transitionAnimation: .flipFromRight)
}
)
)
}
}