swiftuibuttonfocustvostvos9.1

How to perform an action event in tvOS on button focus


I would like to perform certain actions whenever my button is in focus instead of manually tapping it in tvOS.

I have four UIButtons lined up horizontally and when the user just focuses on one of the 4 buttons, I will be showing an UIView with some information.

How can I perform an action without needing to click the button?


Solution

  • You can perform your action when one of the buttons becomes the focused view.

    You could assign a tag to each button, and use the focused button's tag to determine which action to take. For readability, you can define an enum with values for each tag.

    enum FocusedButtonTag: Int {
        case First // Substitute with names that correspond to button's title/action
        case Second
        case Third
        case Fourth
    }
    
    override func didUpdateFocusInContext(context: UIFocusUpdateContext, withAnimationCoordinator coordinator: UIFocusAnimationCoordinator) {
        super.didUpdateFocusInContext(context, withAnimationCoordinator: coordinator)
        guard let button = UIScreen.mainScreen().focusedView as? UIButton else {
            return
        }
        // Update your UIView with the desired information based on the focused button
        switch button.tag {
            case FocusedButtonTag.First.rawValue:
                ... // first button's action
            case FocusedButtonTag.Second.rawValue:
                ... // second button's action
            case FocusedButtonTag.Third.rawValue:
                ... // third button's action
            case FocusedButtonTag.Fourth.rawValue:
                ... // fourth button's action
            default:
                break
        }
    }