JavaFX – 如何在另一个控制器的控制器中使用方法？

使用SceneBuilder。 我有两个阶段，每个阶段都有一个控制器：stage1Controller，stage2Controller。
Stage1Controller：

public class Stage1Controller { @FXML private MenuItem translate; @FXML private Menu file; @FXML private Menu edit; @FXML private Menu help; @FXML private void handleTranslate (ActionEvent event){ translateFirstStage(); //HOW TO ACCESS THE stage2Controller setLabel()?? } private void translateFirstStage(){ file.setText("Fichier"); edit.setText("Modifier"); help.setText("Aide"); } } 

Stage2Controller：

 public class Stage2Controller { @FXML private Label lb; private void setLabel(String string){ lb.setText("string"); } } 

以下是使用2个方法（在Start（Stage primaryStage）方法中调用）在Main.java类中加载两个fxml文件的方法：

 public void firstStage() { try { // Load root layout from fxml file. FXMLLoader loader = new FXMLLoader(); loader.setLocation(Main.class.getResource("view/stage1.fxml")); rootLayout = (BorderPane) loader.load(); // Show the scene containing the root layout. Scene scene = new Scene(rootLayout); primaryStage.setScene(scene); primaryStage.show(); } catch (IOException e) { e.printStackTrace(); } } public void secondStage() { try { // Load root layout from fxml file. FXMLLoader loader = new FXMLLoader(); loader.setLocation(Main.class.getResource("view/stage2.fxml")); XD = (AnchorPane) loader.load(); // Show the scene containing the root layout. Scene scene = new Scene(XD); Stage stage = new Stage(); stage.setScene(scene); stage.show(); } catch (IOException e) { e.printStackTrace(); } } 

• handleTranslate（ActionEvent事件）方法用作第一阶段中MenuItem转换的OnAction方法，它在两个阶段中转换视图。

我如何将setLabel放在handleTranslate方法中？ 谢谢

Answer 1

“快速而肮脏”的方式是为Stage1Controller提供Stage1Controller的引用：

 public class Stage1Controller { private final Stage2Controller stage2Controller ; public void setStage2Controller(Stage2Controller stage2Controller) { this.stage2Controller = stage2Controller ; } // ... @FXML private void handleTranslate (ActionEvent event){ translateFirstStage(); stage2Controller.setLabel(...); } // other code as before ... } 

现在在您的主应用程序中：

 public class MainApp extends Application { private Stage1Controller stage1Controller ; private Stage2Controller stage2Controller ; @Override public void start(Stage primaryStage) { firstStage(); secondStage(); stage1Controller.setStage2Controller(stage2Controller); // ... } public void firstStage() { try { // Load root layout from fxml file. FXMLLoader loader = new FXMLLoader(); loader.setLocation(Main.class.getResource("view/stage1.fxml")); rootLayout = (BorderPane) loader.load(); stage1Controller = loader.getController(); // Show the scene containing the root layout. Scene scene = new Scene(rootLayout); primaryStage.setScene(scene); primaryStage.show(); } catch (IOException e) { e.printStackTrace(); } } public void secondStage() { try { // Load root layout from fxml file. FXMLLoader loader = new FXMLLoader(); loader.setLocation(Main.class.getResource("view/stage2.fxml")); XD = (AnchorPane) loader.load(); stage2Controller = loader.getController(); // Show the scene containing the root layout. Scene scene = new Scene(XD); Stage stage = new Stage(); stage.setScene(scene); stage.show(); } catch (IOException e) { e.printStackTrace(); } } // ... } 

但是，更强大的方法是让两个控制器访问共享模型类，存储数据。 如果使用JavaFX可观察属性表示数据，则控制器可以侦听对其关注的属性的更改。 例如：

 public class Model { private final StringProperty text = new SimpleStringProperty("Initial text..."); public StringProperty textProperty() { return text ; } public final void setText(String text) { textProperty().set(text); } public final String getText() { return textProperty().get(); } // other properties as needed... } 

现在您的控制器将如下所示：

 public class Stage1Controller { private Model model ; public void setModel(Model model) { this.model = model ; } @FXML private void handleTranslate (ActionEvent event){ translateFirstStage(); model.setText(...); // value will appear in stage2 controller's label! } // ... } 

和

 public class Stage2Controller { @FXML private Label lb ; private Model model ; public void setModel(Model model) { lb.textProperty().unbind(); this.model = model ; lb.textProperty().bind(model.textProperty()); } // ... } 

在这种情况下，您的主应用程序看起来像：

 public class MainApp extends Application { private final Model = new Model(); @Override public void start(Stage primaryStage) { // ... } public void firstStage() { try { // Load root layout from fxml file. FXMLLoader loader = new FXMLLoader(); loader.setLocation(Main.class.getResource("view/stage1.fxml")); rootLayout = (BorderPane) loader.load(); Stage1Controller controller = loader.getController(); controller.setModel(model); // Show the scene containing the root layout. Scene scene = new Scene(rootLayout); primaryStage.setScene(scene); primaryStage.show(); } catch (IOException e) { e.printStackTrace(); } } public void secondStage() { try { // Load root layout from fxml file. FXMLLoader loader = new FXMLLoader(); loader.setLocation(Main.class.getResource("view/stage2.fxml")); XD = (AnchorPane) loader.load(); Stage2Controller controller = loader.getController(); controller.setModel(model); // Show the scene containing the root layout. Scene scene = new Scene(XD); Stage stage = new Stage(); stage.setScene(scene); stage.show(); } catch (IOException e) { e.printStackTrace(); } } }