SwiftUI 成功后自动转到下一个视图
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【中文标题】SwiftUI 成功后自动转到下一个视图【英文标题】：SwiftUI automatically go to next view on success 【发布时间】：2020-07-06 17:32:27 【问题描述】：我有一个执行 http 请求的登录视图。一旦我们得到 http 响应，我们就知道用户是否可以进入下一个视图。我想知道如何在不点击的情况下触发下一个视图？我不想做一张纸，因为我想获得全屏模式。我一直在看这个Go to a new view using SwiftUI，但没有运气。从下面的代码中，当我单击 Press on me 导航链接时，我可以转到正确的视图，但是我需要相同的功能才能工作，而无需单击下面显示 decode 的 http 响应。 status == 1 因为用户已成功验证。
struct ContentView: View
@State var email: String = ""
@State var password: String = ""
@State var message: String = ""
@State var status: Int = -10
@State var showActive = true
var body: some View
NavigationView
ZStack
Color(UIColor.systemGroupedBackground)
.edgesIgnoringSafeArea(.all)
VStack(alignment: .center)
Spacer()
NavigationLink(destination: MainView())
Text("Press on me")
.buttonStyle(PlainButtonStyle()) // This works when clicked
TextField("Email", text: $email)
.padding(10)
.textFieldStyle(RoundedBorderTextFieldStyle())
.background(Color(UIColor(hexString: ForestGreen)))
.foregroundColor(Color.black)
SecureField("Password", text: $password)
.padding(10)
.textFieldStyle(RoundedBorderTextFieldStyle())
.background(Color(UIColor(hexString: ForestGreen)))
.foregroundColor(Color.black)
Button(action:
guard let url = URL(string:ConnectionString+"profile/login") else return
let parameter = "email=\(self.email)&password=\(self.password)"
let request = RequestObject(AddToken: true, Url: url, Parameter: parameter)
URLSession.shared.dataTask(with:request, completionHandler: (data, response, error) in
if let decode = try? JSONDecoder().decode(ProfileCodable.self, from: data!)
self.status = decode.status ?? -10
self.message = decode.message ?? ""
if decode.status == 0
print("Invalid Credentials")
else if decode.status == 1
// ** Go to next View here **
else if decode.status == -1
print("Error")
else
print("No Response")
).resume()
)
Text("Login")
.padding(10)
.frame(minWidth: 0, maxWidth: .infinity)
.font(.system(size: 22))
.foregroundColor(Color(UIColor(hexString: "#006622")))
.overlay(
RoundedRectangle(cornerRadius: 40)
.stroke(Color.black, lineWidth: 1))
.padding([.top],40)
if self.status == 0
Text(self.message)
.foregroundColor(.red)
.font(.system(size: 20))
.padding([.top],30)
Spacer()
.padding()
【问题讨论】：
这能回答你的问题吗？ SwiftUI NavigationLink: Navigate to a destination view AFTER running account creation code successfully 【参考方案1】：试试这个（scratchy - 未测试，因为由于缺少依赖项而无法编译），所以在你身边适应：
struct ContentView: View
@State var email: String = ""
@State var password: String = ""
@State var message: String = ""
@State var status: Int = -10
@State var showActive = false // << seems this state, so false
var body: some View
NavigationView
ZStack
Color(UIColor.systemGroupedBackground)
.edgesIgnoringSafeArea(.all)
VStack(alignment: .center)
Spacer()
TextField("Email", text: $email)
.padding(10)
.textFieldStyle(RoundedBorderTextFieldStyle())
.background(Color(UIColor(hexString: ForestGreen)))
.foregroundColor(Color.black)
SecureField("Password", text: $password)
.padding(10)
.textFieldStyle(RoundedBorderTextFieldStyle())
.background(Color(UIColor(hexString: ForestGreen)))
.foregroundColor(Color.black)
Button(action:
guard let url = URL(string:ConnectionString+"profile/login") else return
let parameter = "email=\(self.email)&password=\(self.password)"
let request = RequestObject(AddToken: true, Url: url, Parameter: parameter)
URLSession.shared.dataTask(with:request, completionHandler: (data, response, error) in
if let decode = try? JSONDecoder().decode(ProfileCodable.self, from: data!)
self.status = decode.status ?? -10
self.message = decode.message ?? ""
if decode.status == 0
print("Invalid Credentials")
else if decode.status == 1
self.showActive = true // << here !!
else if decode.status == -1
print("Error")
else
print("No Response")
).resume()
)
Text("Login")
.padding(10)
.frame(minWidth: 0, maxWidth: .infinity)
.font(.system(size: 22))
.foregroundColor(Color(UIColor(hexString: "#006622")))
.overlay(
RoundedRectangle(cornerRadius: 40)
.stroke(Color.black, lineWidth: 1))
.padding([.top],40)
.background(
// activated by state programmatically !!
NavigationLink(destination: MainView(), isActive: $self.showActive)
EmptyView() // << just hide
.buttonStyle(PlainButtonStyle())
)
if self.status == 0
Text(self.message)
.foregroundColor(.red)
.font(.system(size: 20))
.padding([.top],30)
Spacer()
.padding()
【讨论】：
【参考方案2】：只需使用导航链接的 isActive 属性。它看起来像这样：
NavigationLink(destination: MainView(), isActive: $mainViewActive)
Text("Press on me")
.buttonStyle(PlainButtonStyle())
您还应该在视图中声明该变量：
@State var mainViewActive = false
然后在成功登录时只需将值更改为 true。如果您也不想显示实际链接，请使用 EmptyView() 作为包装器。所以它看起来像这样：
NavigationLink(destination: MainView(), isActive: $mainViewActive)
EmptyView()
【讨论】：
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