JavaFX - handler is without parametr if fx:root used

Lets say that I want to create custom Button. If I use fx:include, I can specify controller class and then create handler that accept ActionEvent as parametr. Quite standard behaviour, example follow.


xmlns:fx="http://javafx.com/fxml"

fx:controller="sample.MySecondButton"

prefHeight="400.0" prefWidth="600.0">