1️⃣ Forms in SwiftUI

Form automatically applies grouped styling for data entry screens.

Form {
    Section(header: Text("Profile Info")) {
        TextField("Name", text: $name)
        SecureField("Password", text: $password)
    }
    Section {
        Toggle("Receive Notifications", isOn: $notificationsEnabled)
    }
}

2️⃣ Updating AddFriendView with Form & Validation

We’ll improve the Add Friend screen from Day 14.

import SwiftUI

struct AddFriendView: View {
    @Environment(\.dismiss) private var dismiss
    @State private var name: String = ""
    @State private var isOnline: Bool = false
    @State private var errorMessage: String?
    
    let onAdd: (Friend) -> Void
    
    var body: some View {
        NavigationStack {
            Form {
                Section("New Friend") {
                    TextField("Name", text: $name)
                        .autocorrectionDisabled()
                        .textInputAutocapitalization(.words)
                        .submitLabel(.done)
                        .onSubmit { saveFriend() }
                    
                    Toggle("Online", isOn: $isOnline)
                }
                
                if let error = errorMessage {
                    Section {
                        Text(error)
                            .foregroundStyle(.red)
                    }
                }
            }
            .navigationTitle("Add Friend")
            .toolbar {
                ToolbarItem(placement: .topBarLeading) {
                    Button("Cancel") { dismiss() }
                }
                ToolbarItem(placement: .topBarTrailing) {
                    Button("Save") { saveFriend() }
                        .disabled(name.trimmingCharacters(in: .whitespaces).isEmpty)
                }
            }
        }
    }
    
    private func saveFriend() {
        let trimmedName = name.trimmingCharacters(in: .whitespaces)
        guard !trimmedName.isEmpty else {
            errorMessage = "Name cannot be empty"
            return
        }
        
        onAdd(.init(name: trimmedName, isOnline: isOnline))
        dismiss()
    }
}

3️⃣ Key improvements from Day 14

• .autocorrectionDisabled() → prevents unwanted spelling corrections.

• .textInputAutocapitalization(.words) → capitalizes each word in names.

• .submitLabel(.done) → changes keyboard button label to “Done”.

• .onSubmit → triggers save when pressing “Done” on keyboard.

• Validation → shows error message if field is empty.

4️⃣ Adding Secure Input (optional)

If you were building a login screen:

SecureField("Password", text: $password)

This hides the entered text with dots.

🛠 Practice

1. Add a TextField for “Nickname” that’s optional.

2. Add a DatePicker for “Birthday” and display it in FriendDetailView.

3. Prevent adding more than 1 friend with the same name (check in onAdd).

4. Disable the Save button if name is empty and online status is false.