Support hardware keyboards in your app

0:01 - PlayerViewController

class PlayerViewController: UIViewController {

    override var canBecomeFirstResponder: Bool {
        return true 
    }

    override func viewDidAppear(_ animated: Bool) {
        becomeFirstResponder()
    }

    override var keyCommands: [UIKeyCommand]? {
        return [
            UIKeyCommand(title: NSLocalizedString("PLAY_PAUSE", comment: "…"),
                        action: #selector(playPause),
                         input: " ")
        ]
    }
}

0:02 - SongListTableViewController

class SongListTableViewController: UITableViewController {

    override var canBecomeFirstResponder: Bool {
        return true
    }
    
    override func viewDidAppear(_ animated: Bool) {
        becomeFirstResponder()
    }
    
    /* UIResponderStandardEditActions */

    override func selectAll(_ sender: Any?) { … }

    override func copy(_ sender: Any?) { … }

    override func paste(_ sender: Any?) { … }

}

0:03 - UIKeyCommand

class UIKeyCommand : UICommand {
    ...
}

override func buildMenu(with builder: UIMenuBuilder) {
    builder.replaceChildren(ofMenu: .file) { children in
        return [ UIKeyCommand() ] + children
    }
}

0:04 - Extending selection with keyboard

optional func tableView(_ tableView: UITableView,
       shouldBeginMultipleSelectionInteractionAt indexPath: IndexPath) -> Bool

optional func tableView(_ tableView: UITableView,
       didBeginMultipleSelectionInteractionAt indexPath: IndexPath)

0:05 - recognizedDragGesture

func recognizedDragGesture(_ panGesture: UIPanGestureRecognizer) {

    if panGesture.modifierFlags.contains(.command) {
        snapToGrid = true
    } else if panGesture.modifierFlags.contains(.shift) {
        constrainAspectRatio = true
    }
    
    ...
}

0:06 - Responding to raw keyboard events

class UIResponder: NSObject {
    func pressesBegan(_ presses: Set<UIPress>,
                     with event: UIPressesEvent)
    
    func pressesEnded(_ presses: Set<UIPress>,
                     with event: UIPressesEvent)
}

0:07 - CanvasViewController

class CanvasViewController: UIViewController {
     
     override func pressesBegan(_ presses: Set<UIPress>, with event: UIPressesEvent?) {
         for press in presses {
             guard let key = press.key else { continue }
             switch key.keyCode {
             case .keyboardUpArrow: startMoveUp()
             case .keyboardDownArrow: startMoveDown()
                 …
             }
     }
     }

     override func pressesEnded(_ presses: Set<UIPress>, with event: UIPressesEvent?) {
         stopMoving()
     }

}

0:08 - CanvasViewController modifier flags

class CanvasViewController: UIViewController {

    override func pressesBegan(_ presses: Set<UIPress>, with event: UIPressesEvent?) {
        var selectWhileMoving = false
        for press in presses {
            guard let key = press.key else { continue }
            if key.modifierFlags.contains(.shift) {
                selectWhileMoving = true
            }
                
            switch key.keyCode {
            case .keyboardUpArrow: startMoveUp()
                    
            }
        }
    }
}