class ExampleActivity  :  AppCompatActivity() {


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        changeKeyboardStateButton.setOnClickListener {
            if(isKeyboardShown) {
                hideKeyboard() 
            } else {
                editText.showKeyboard()
            }
        }
        onKeyboardShowChanged { shown: Boolean, height: Int ->
            // your use of shown and height
        }
    }
}