Automate switching between languages

src/main/java/app/controllers/MenubarController.java

@@ -5,11 +5,16 @@ import java.net.URL;
 import java.util.ResourceBundle;
 
 import com.google.common.eventbus.EventBus;
+import com.google.common.eventbus.Subscribe;
 
+import app.events.LanguageChangedEvent;
 import app.model.Model;
+import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
 import javafx.fxml.Initializable;
 import javafx.scene.control.MenuBar;
+import javafx.scene.control.RadioMenuItem;
+import javafx.scene.control.ToggleGroup;
 import javafx.stage.DirectoryChooser;
 import javafx.stage.FileChooser;
 import javafx.stage.Stage;
@@ -17,11 +22,13 @@ import javafx.stage.Stage;
 public class MenubarController implements Initializable, Controller {
 
   private EventBus eventBus;
-  private Model model;
 
   @FXML
   private MenuBar menubar;
 
+  @FXML
+  private ToggleGroup languageToggleGroup;
+
   @FXML
   public String handleOpenFile() {
     FileChooser fc = new FileChooser();
@@ -76,12 +83,27 @@ public class MenubarController implements Initializable, Controller {
   }
 
   /**
-   * Links the controller to the global model
-   * 
-   * @param model The model to be linked
+   * Handles the event where the language was change from the menu.
    */
-  public void setModel(Model model) {
-    this.model = model;
+  @FXML
+  private void handleLanguageChange(ActionEvent event) {
+    this.eventBus.post(
+      new LanguageChangedEvent(
+        ((RadioMenuItem) event.getSource()).getText()));
   }
 
+  /**
+   * Updates menubuttons whenever the language is changed
+   */
+  @Subscribe
+  private void handle(LanguageChangedEvent event) {
+    this.languageToggleGroup
+      .getToggles()
+      .stream()
+      .map(RadioMenuItem.class::cast)
+      .filter(t -> t.getId().equals("toggle" + event.getLanguage()))
+      .findFirst()
+      .orElseThrow()
+      .setSelected(true);
+  }
 }