JavaFX - 如何从另一个控制器使用控制器中的方法? [英] JavaFX - How to use a method in a controller from another controller?

问题描述

使用 SceneBuilder.我有 2 个阶段，每个阶段都有一个控制器:
stage1Controller,
stage2Controller.
Stage1Controller :

Working with SceneBuilder. I have 2 stages, each one with a controller:
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");
    }
}

以下是使用两种方法在 Main.java 类中加载两个 fxml 文件的方法
(在 Start(Stage primaryStage) 方法中调用):

Here is how both fxml files are loaded in Main.java class using 2 methods
(called in Start(Stage primaryStage) method):

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 event) 方法用作第一个 Stage 中 MenuItem translate 的 OnAction 方法，它转换视图在两个阶段.
  
• The handleTranslate(ActionEvent event) method is used as an OnAction method for the MenuItem translate in the first Stage, it translates the view in both stages.
  

如何将 setLabel 放入 handleTranslate 方法中?谢谢

How Can i put setLabel in handleTranslate Method ? Thanks

推荐答案

又快又脏"的方法是给 Stage1Controller 一个对 Stage2Controller 的引用:

The "quick and dirty" way is to give the Stage1Controller a reference to the Stage2Controller:

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();
        }
    }

    // ...
}

不过，一个更健壮的方法是让两个控制器访问共享模型类，存储数据.如果您使用 JavaFX 可观察属性表示数据，则控制器可以监听他们关心的属性的变化.例如:

A more robust approach to this, though, is to let both controllers access a shared model class, storing the data. If you represent the data using JavaFX observable properties, the controllers can listen for changes on the properties they care about. For example:

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:

Now your controllers will look like this:

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，您的主应用程序如下所示:

And in this case your main app looks like:

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();
        }
    }
}

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