Modify Sample.fxml in the last article "Create GridPane using FXML" to replace GridPane with AnchorPane.
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.text.*?>
<?import javafx.scene.textfield.*?>
<AnchorPane fx:controller="javafxml.Sample" xmlns:fx="http://javafx.com/fxml"
prefHeight="200" prefWidth="400" >
<Text text="java-Buddy" AnchorPane.topAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0"/>
<Label text="Who are you?" AnchorPane.topAnchor="25.0" AnchorPane.leftAnchor="0.0"/>
<TextField id="textfield" fx:id="textfield" AnchorPane.topAnchor="25.0" AnchorPane.rightAnchor="0.0"/>
<Button id="button" text="Click Me!"
onAction="#handleButtonAction" fx:id="button"
AnchorPane.topAnchor="50.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0"/>
<Label id="label" fx:id="label" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0"/>
</AnchorPane>