FocusedValues.swift

extension FocusedValues {
    var myKey: Binding<String>? {
        get { self[MyFocusKey.self] }
        set { self[MyFocusKey.self] = newValue }
    }
    
    struct MyFocusKey: FocusedValueKey {
        typealias Value = Binding<String>
    }
}

LearningFocusPropertyWrappers.swift

struct LearningFocusPropertyWrappers: View {
    @State private var textEditorText: String = "TextEditor"
    @State private var secureFieldText: String = ""
    
    @State private var focusStateText: String = ""
    @FocusState private var focusState: Field?
    enum Field: Hashable {
        case username
        case password
        case state
        case value
        case object
        case binding
    }
    
    // ???
    @State private var accessibilityFocusStateText: String = ""
    @AccessibilityFocusState(for: .voiceOver) var accessibilityFocusState: Bool
    
    @FocusedObject var data: DataModel?
    @StateObject var model = DataModel()
    final class DataModel: ObservableObject {
        @Published var text = ""
    }
    
    @State private var focusedValueText: String = ""
    @FocusedValue(\.myKey) var focusedValue
    
    @State private var focusedBindingText: String = ""
    @FocusedBinding(\.myKey) var focusedBinding
    
    var body: some View {
        VStack {
            Text("Learning focused modifier👋")
                .font(.system(.largeTitle, design: .rounded, weight: .black))
            
            Divider()
            
            focusedStateExample
            
            Divider()
            
            focusedValueExample
            
            Divider()
            
            focusedObjectExample
            
            Divider()
            
            focusedBindingExample
        }
        .padding()
    }
    
    @ViewBuilder
    private var focusedStateExample: some View {
        TextField("", text: $focusStateText, prompt: Text("TextField placeholder"), axis: .vertical)
            .textFieldStyle(RoundedBorderTextFieldStyle())
            .focused($focusState, equals: .state)
        
        TextEditor(text: $textEditorText)
            .padding(4)
            .border(Color.gray, width: 1)
            .focused($focusState, equals: .username)
        
        SecureField("Password", text: $secureFieldText)
                .focused($focusState, equals: .password)
                .textFieldStyle(RoundedBorderTextFieldStyle())
        
        Button("Remove Focused") {
            focusState = .none
        }
        .controlSize(.extraLarge)
        .buttonStyle(.borderedProminent)
    }
    
    @ViewBuilder
    private var focusedValueExample: some View {
        Text(focusedValueText)
            
        TextField("", text: $focusedValueText, prompt: Text("TextField placeholder"), axis: .vertical)
            .textFieldStyle(RoundedBorderTextFieldStyle())
            .focused($focusState, equals: .value)
            .focusedValue(\.myKey, focusedValue)
        
        Button("Remove FocusedValue") {
            focusState = .none
            focusedValueText = ""
            // focusedValue = "focusedValueText"
            // Cannot assign to property: 'focusedForFocusedValue' is a get-only property
        }
        .controlSize(.extraLarge)
        .buttonStyle(.borderedProminent)
    }
    
    @ViewBuilder
    private var focusedObjectExample: some View {
        if let text = data?.text {
            Text(text)
        }
        TextField("", text: $model.text, prompt: Text("TextField placeholder"), axis: .vertical)
            .textFieldStyle(RoundedBorderTextFieldStyle())
            .focused($focusState, equals: .object)
            .focusedObject(model)
        
        Button("Remove FocusedObject") {
            focusStateText = ""
            focusState = .none
            // model = DataModel()
            // Cannot assign to property: 'model' is a get-only property
        }
        .controlSize(.extraLarge)
        .buttonStyle(.borderedProminent)
    }
    
    @ViewBuilder
    private var focusedBindingExample: some View {
        TextField("", text: $focusedBindingText, prompt: Text("TextField placeholder"), axis: .vertical)
            .textFieldStyle(RoundedBorderTextFieldStyle())
            .focused($focusState, equals: .binding)
            .focusedValue(\.myKey, $focusedBindingText)
        
        Text(focusedBinding ?? "FocusedBinding is nil")
        
        Button("Change FocusedBinding") {
            focusedBindingText = ""
            focusedBinding = "\(Int.random(in: 0..<100))"
            focusState = .none
        }
        .controlSize(.extraLarge)
        .buttonStyle(.borderedProminent)
    }
}

2024-07-21.22.43.43.mov