Android AlertDialog Rx extension

AlertDialog+Rx.kt

import android.content.DialogInterface
import androidx.appcompat.app.AlertDialog
import com.jakewharton.rxbinding2.view.clicks
import io.reactivex.Maybe
import io.reactivex.Single

/**
 * Sets the dialog non-cancelable. Emits either {@link DialogInterface#BUTTON_POSITIVE},
 * {@link DialogInterface#BUTTON_NEGATIVE} or {@link DialogInterface#BUTTON_NEUTRAL} and dismisses
 * the dialog.
 */
@androidx.annotation.CheckResult
fun AlertDialog.clicks(): Single<Int> {
    setCancelable(false)
    return Maybe.merge(
            getButton(DialogInterface.BUTTON_POSITIVE).clicks().firstElement().map { DialogInterface.BUTTON_POSITIVE },
            getButton(DialogInterface.BUTTON_NEGATIVE).clicks().firstElement().map { DialogInterface.BUTTON_NEGATIVE },
            getButton(DialogInterface.BUTTON_NEUTRAL).clicks().firstElement().map { DialogInterface.BUTTON_NEUTRAL })
            .firstOrError()
            .doOnSuccess {
                dismiss()
            }
}