Detect key press without modifier

Question

I'd like to capture a keypress in my Catalyst app.

UIKeyCommand(input: "", modifierFlags: nil, action: #selector(singleShift))

Unfortunately modifierFlags can't be nil and NSEvent isn't supported on Catalyst. Is there a way to detect single press keys? e.g. for a keyboard app or a game?

Answer 1

The field modifierFlags isn't optional, so you can't pass nil. It is of the type UIKeyModifierFlags which is an OptionSet, so if you don't want to pass a modifier you can simply pass an empty array.

class ViewController: UIViewController {
    override var keyCommands: [UIKeyCommand]? {
        [UIKeyCommand(input: UIKeyCommand.inputPageUp,
                      modifierFlags: [],
                      action: #selector(pageUpPressed(_:)))]
    }
}