How to make UIViewRepresentable focusable on tvOS in SwiftUI? - swiftui

Question

The title says it all - I can't get focus on UIViewRepresentable in SwiftUI on tvOS. Any view that conforms to View protocol can be focused without problems but neither UIViewRepresentable nor UIViewControllerRepresentable can.
Any ideas?
This code works:
struct ContentView: View {
var body: some View {
Text("Hello, World!")
.focusable()
.onExitCommand {
print("Menu button pressed")
}
}
}
This one does not:
struct ContentView: View {
var body: some View {
ViewRepresentable()
.focusable()
.onExitCommand {
print("Menu button pressed")
}
}
}
struct ViewRepresentable: UIViewRepresentable {
func makeUIView(context: Context) -> UIView {
let view = UIView()
view.backgroundColor = .red
return view
}
func updateUIView(_ uiView: UIView, context: Context) {
}
}
Thanks!

Answer 1

You need to make a UIView subclass that overrides canBecomeFocused to return true. You probably want to also override didUpdateFocus(in:with:) if you want to respond to focus.
For reference here is a utility class I made to let me have focusable UIViews, and respond to remote swipes and clicks.
import UIKit
#available (iOS, unavailable)
#available (macCatalyst, unavailable)
class UserInputView: UIView {
weak var pressDelegate: PressableDelegate?
weak var touchDelegate: TouchableDelegate?
var touchStarted: CGFloat = 0
var lastTouch: CGFloat = 0
override init(frame: CGRect) {
super.init(frame: frame)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
touchStarted = touches.first?.location(in: nil).x ?? 0
lastTouch = touchStarted
touchDelegate?.touchDown()
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
let thisTouch = touches.first?.location(in: nil).x ?? 0
touchDelegate?.touchMove(amount: Double((thisTouch - lastTouch)/(touches.first?.window?.frame.width ?? 1920)))
lastTouch = touches.first?.location(in: nil).x ?? 0
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
touchDelegate?.touchUp()
}
override func pressesBegan(_ presses: Set<UIPress>, with event: UIPressesEvent?) {
if isClick(presses) {
pressDelegate?.press(pressed: true)
} else {
superview?.pressesBegan(presses, with: event)
}
}
override func pressesEnded(_ presses: Set<UIPress>, with event: UIPressesEvent?) {
if isClick(presses) {
pressDelegate?.press(pressed: false)
pressDelegate?.clicked()
} else {
superview?.pressesEnded(presses, with: event)
}
}
private func isClick(_ presses: Set<UIPress>?) -> Bool {
return presses?.map({ $0.type }).contains(.select) ?? false
}
override func didUpdateFocus(in context: UIFocusUpdateContext, with coordinator: UIFocusAnimationCoordinator) {
pressDelegate?.focus(focused: isFocused)
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override var canBecomeFocused: Bool {
return true
}
}