Alert dialog with Spinner in customView, using Anko (Kotlin)

gistfile1.txt

// Items for spinner
val items = arrayOf("One", "Two", "Three", "Four", "Five")

// Alert with a spinner
alert("Example Alert") {
            title = "Example Alert"
            customView {
                verticalLayout {
                    spinner {
                        adapter = ArrayAdapter(ctx, android.R.layout.simple_spinner_dropdown_item, countries)
                    }
                }
            }
        }.show()

countries should probably be items, or vice versa.