IQKeyboardNotification

import IQKeyboardNotification

class ViewController: UIViewController {

    private let keyboard: IQKeyboardNotification = .init()

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)

        // Subscribe
        keyboard.subscribe(identifier: "YOUR_UNIQUE_IDENTIFIER") { event, frame in
            print(frame)
            // Write your own logic here based on event and keyboard frame
        }
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)

        // Unsubscribe
        keyboard.unsubscribe(identifier: "YOUR_UNIQUE_IDENTIFIER")
    }
}