main.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?scenebuilder-stylesheet vista.css?>

<VBox prefHeight="200.0" prefWidth="300.0" xmlns:fx="http://javafx.com/fxml" fx:controller="MainController">
  <children>
    <Label fx:id="headerLabel" maxWidth="1.7976931348623157E308" text="Header" VBox.vgrow="NEVER" />
    <StackPane fx:id="vistaHolder" VBox.vgrow="ALWAYS" />
  </children>
</VBox>

Main.java

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;

import java.io.IOException;

/**
 * Main application class.
 */
public class Main extends Application {

    @Override
    public void start(Stage stage) throws Exception{
        stage.setTitle("Vista Viewer");

        stage.setScene(
            createScene(
                loadMainPane()
            )
        );

        stage.show();
    }

    /**
     * Loads the main fxml layout.
     * Sets up the vista switching VistaNavigator.
     * Loads the first vista into the fxml layout.
     *
     * @return the loaded pane.
     * @throws IOException if the pane could not be loaded.
     */
    private Pane loadMainPane() throws IOException {
        FXMLLoader loader = new FXMLLoader();

        Pane mainPane = (Pane) loader.load(
            getClass().getResourceAsStream(
                VistaNavigator.MAIN
            )
        );

        MainController mainController = loader.getController();

        VistaNavigator.setMainController(mainController);
        VistaNavigator.loadVista(VistaNavigator.VISTA_1);

        return mainPane;
    }

    /**
     * Creates the main application scene.
     *
     * @param mainPane the main application layout.
     *
     * @return the created scene.
     */
    private Scene createScene(Pane mainPane) {
        Scene scene = new Scene(
            mainPane
        );

        scene.getStylesheets().setAll(
            getClass().getResource("vista.css").toExternalForm()
        );

        return scene;
    }

    public static void main(String[] args) {
        launch(args);
    }
}

MainController.java

import javafx.fxml.FXML;
import javafx.scene.Node;
import javafx.scene.layout.StackPane;

/**
 * Main controller class for the entire layout.
 */
public class MainController {

    /** Holder of a switchable vista. */
    @FXML
    private StackPane vistaHolder;

    /**
     * Replaces the vista displayed in the vista holder with a new vista.
     *
     * @param node the vista node to be swapped in.
     */
    public void setVista(Node node) {
        vistaHolder.getChildren().setAll(node);
    }

}

vista.css

/**
 * vista.css
 *   Place in the same source directory as Main.java
 *   Ensure that your build system copies this file to your build output directory.
 */

#headerLabel {
    -fx-background-color: steelblue;
    -fx-text-fill: white;
    -fx-padding: 5px;
}

#vistaHolder {
    -fx-background-color: lightgrey;
}

#vista1 {
    -fx-background-color: aliceblue;
}

#vista2 {
    -fx-background-color: coral;
}

.button {
    -fx-base: lightblue;
    -fx-font-size: 20px;
}

vista1.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?scenebuilder-stylesheet vista.css?>

<StackPane fx:id="vista1" xmlns:fx="http://javafx.com/fxml" fx:controller="Vista1Controller">
  <children>
    <Button mnemonicParsing="false" onAction="#nextPane" text="Next Pane" />
  </children>
</StackPane>

Vista1Controller.java

import javafx.event.ActionEvent;
import javafx.fxml.FXML;

/**
 * Controller class for the first vista.
 */
public class Vista1Controller {

    /**
     * Event handler fired when the user requests a new vista.
     *
     * @param event the event that triggered the handler.
     */
    @FXML
    void nextPane(ActionEvent event) {
        VistaNavigator.loadVista(VistaNavigator.VISTA_2);
    }

}

vista2.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?scenebuilder-stylesheet vista.css?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.layout.StackPane?>
<StackPane fx:id="vista2" xmlns:fx="http://javafx.com/fxml" fx:controller="Vista2Controller">
  <children>
    <Button mnemonicParsing="false" onAction="#previousPane" text="Previous Pane" />
  </children>
</StackPane>

Vista2Controller.java

import javafx.event.ActionEvent;
import javafx.fxml.FXML;

/**
 * Controller class for the second vista.
 */
public class Vista2Controller {

    /**
     * Event handler fired when the user requests a previous vista.
     *
     * @param event the event that triggered the handler.
     */
    @FXML
    void previousPane(ActionEvent event) {
        VistaNavigator.loadVista(VistaNavigator.VISTA_1);
    }

}

VistaNavigator.java

import javafx.fxml.FXMLLoader;

import java.io.IOException;

/**
 * Utility class for controlling navigation between vistas.
 *
 * All methods on the navigator are static to facilitate
 * simple access from anywhere in the application.
 */
public class VistaNavigator {

    /**
     * Convenience constants for fxml layouts managed by the navigator.
     */
    public static final String MAIN    = "main.fxml";
    public static final String VISTA_1 = "vista1.fxml";
    public static final String VISTA_2 = "vista2.fxml";

    /** The main application layout controller. */
    private static MainController mainController;

    /**
     * Stores the main controller for later use in navigation tasks.
     *
     * @param mainController the main application layout controller.
     */
    public static void setMainController(MainController mainController) {
        VistaNavigator.mainController = mainController;
    }

    /**
     * Loads the vista specified by the fxml file into the
     * vistaHolder pane of the main application layout.
     *
     * Previously loaded vista for the same fxml file are not cached.
     * The fxml is loaded anew and a new vista node hierarchy generated
     * every time this method is invoked.
     *
     * A more sophisticated load function could potentially add some
     * enhancements or optimizations, for example:
     *   cache FXMLLoaders
     *   cache loaded vista nodes, so they can be recalled or reused
     *   allow a user to specify vista node reuse or new creation
     *   allow back and forward history like a browser
     *
     * @param fxml the fxml file to be loaded.
     */
    public static void loadVista(String fxml) {
        try {
            mainController.setVista(
                FXMLLoader.load(
                    VistaNavigator.class.getResource(
                        fxml
                    )
                )
            );
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}