JavaFX 2 and Internationalization

The basic steps (among others) of a java app internationalizing, are Localelizing and resource bundling. In JavaFX, you can use FXMLLoader#setResources() for that purposes. Here a SSCCE demo to demonstrate it. The codes are self-descriptive.
Demo package structure:

bundledemo
    |------ BundleDemo.java
    |------ MyController.java
    |------ MyView.fxml  
bundles
    |------ MyBundle_en.properties
    |------ MyBundle_kg.properties

MyBundle_en.properties

key1=Name Surname
key2=How are you?

MyBundle_kg.properties

key1=Aты Жөнү
key2=Кандайсың?

MyView.fxml

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

<?import javafx.scene.layout.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.*?>

<BorderPane fx:controller="bundledemo.MyController" xmlns:fx="http://javafx.com/fxml">
    <top>
        <!-- This label's text will be set by the controller -->
        <Label fx:id="lblTextByController"/> 
    </top>
    <center>
        <!-- This label's text will be taken from the bundle automatically -->
        <Label text="%key2"/>
    </center>
</BorderPane>

MyController.java

package bundledemo;

import java.net.URL;
import java.util.ResourceBundle;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;

public class MyController implements Initializable {

    @FXML private Label lblTextByController;
    private ResourceBundle bundle;
    
    @Override
    public void initialize(URL location, ResourceBundle resources) {
        bundle = resources;
        lblTextByController.setText(bundle.getString("key1"));
    }
}

BundleDemo.java

package bundledemo;
// imports are ignored.

public class BundleDemo extends Application {

    private Stage stage;

    @Override
    public void start(Stage primaryStage) {
        stage = primaryStage;
        Button btnEN = new Button();
        btnEN.setText("English");
        btnEN.setOnAction(new EventHandler<ActionEvent>() {
            @Override public void handle(ActionEvent event) {
                loadView(new Locale("en", "EN"));
            }
        });

        Button btnKG = new Button();
        btnKG.setText("Kyrgyz");
        btnKG.setOnAction(new EventHandler<ActionEvent>() {
            @Override public void handle(ActionEvent event) {
                loadView(new Locale("kg", "KG"));
            }
        });

        VBox root = new VBox(20);
        root.getChildren().add(HBoxBuilder.create().spacing(10).style("-fx-background-color: gray").padding(new Insets(5)).children(btnEN, btnKG).build());
        root.getChildren().add(new StackPane());
        primaryStage.setScene(new Scene(root, 300, 250));
        primaryStage.show();
    }

    private void loadView(Locale locale) {
        try {
            FXMLLoader fxmlLoader = new FXMLLoader();
            fxmlLoader.setResources(ResourceBundle.getBundle("bundles.MyBundle", locale));
            Pane pane = (BorderPane) fxmlLoader.load(this.getClass().getResource("MyView.fxml").openStream());
            // replace the content
            StackPane content = (StackPane) ((VBox) stage.getScene().getRoot()).getChildren().get(1);
            content.getChildren().clear();
            content.getChildren().add(pane);
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }

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

Screenshot:

---

If your internationalized text needs to be rendered in a font that might be on the user’s target system, then you can either:

1. Embed the font with your application:

• How to embed .ttf fonts is JavaFx 2.2?

OR

2. Use web(Google) fonts in JavaFX.

If the required font is not available, then the internationalized text might be displayed as unintelligible gibberish, even though everything else about the setup is fine.