删除表单 SwiftUI 中的行

Question

我有一个表单，如果用户没有向电子邮件和密码字段提供足够的凭据，则会显示提示。问题是提示在它们所在的位置（在电子邮件和密码下）创建了一个额外的行。

我尝试隐藏分隔符，但随后留下了巨大的空间间隙。有没有办法可以删除列表行，并在文本出现时让每个元素向下移动？密码提示并不那么明显，因为按钮和行之间仍然有空间。

NavigationView{
            ZStack{
                Form{
        Section(){
            TextField("FirstName", text: $userInformation.firstname)
            TextField("LastName", text: $userInformation.lastname)
            
            TextField("Email", text: $userInformation.email)
            Text(userInformation.emailPrompt)
                .font(.caption).italic().foregroundColor(.red)
                .listStyle(.inset)
                          
            SecureField("Passsword", text: $userInformation.password
                        ).autocapitalization(.none)
            Text(userInformation.passwordPrompt)
            
                .font(.caption).italic().foregroundColor(.red)
        }
       
                    .listRowBackground(Color.clear)
                    .padding()
                .navigationBarTitle(Text("Lets Get Started"))
                .navigationBarTitleDisplayMode(.automatic)
                .font(.system(size:18))
                    
                .listStyle(GroupedListStyle())
               
            }
               
                    NavigationLink(destination: JournalEntryMain() .navigationBarHidden(true)){
                        Text("Sign Up")
                            .frame(width: 250, height: 20)
                            .foregroundColor(.white)
                            .padding()
                           // .multilineTextAlignment(.leading)
                            .background(LinearGradient(gradient: Gradient(colors: [.orange, .pink]), startPoint: .leading, endPoint: .bottom))
                            .font(.title3)
                            .background(.clear)
                            .cornerRadius(5)
                            .offset(y:30)
                            .opacity(userInformation.isSignUpComplete ? 1 : 0.5)
                }
           
class FormViewModel: ObservableObject {
    @Published var firstname = ""
    @Published var lastname = ""
    @Published var email = ""
    @Published var gender = ""
    @Published var password = ""
    
    func isPasswordValid() -> Bool {
        let passwordTest = NSPredicate(format: "SELF MATCHES%@", "^(?=.*\\d)(?=.*[a-z])(?=.*[A-Z]).{8,15}$")
        return passwordTest.evaluate(with: password)
    }
    func isEmailValid() -> Bool {
        let emailTest = NSPredicate(format: "SELF MATCHES%@", "^([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.)|(([a-zA-Z0-9\\-]+\\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\\]?)$")
        return emailTest.evaluate(with: email)
    }
    
    //email and password prompts if incomplete or incorrect
    var emailPrompt: String {
        if isEmailValid() || email == "" {
            return ""
        } else {
            return "*Please enter a valid email address"
        }
    }
    
    var passwordPrompt: String {
        if isPasswordValid() || password == ""{
            return ""
        } else {
            return "*Password must be 8-15 letters, with atleast one uppercase and one number"
        }
    }
    
    var isSignUpComplete: Bool {
        if !isPasswordValid() || !isEmailValid() || firstname == "" || lastname == "" {
            return false
        }
        return true
    }
    
    
}

     

Answer 1

最简单的方法是条件：

if userInformation.passwordPrompt != "" {
    Text(userInformation.passwordPrompt)
        .font(.caption).italic().foregroundColor(.red)
}

这将有条件地将其从视图中删除。您还可以设置出现/消失的动画。