JavaFX：window 为黑色且不显示 SceneBuilder 更新

Question

I'm learning JavaFX and I'm trying to make a graphical app with SceneBuilder, but the window is blank with nothing on it. I added some buttons to the window on SceneBuilder, but I can't see them when I run the app. The app is based on MVC:

Main:

package application;

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



public class Main extends Application {
    @Override
    public void start(Stage stage) {
        try {
            FXMLLoader loader = new FXMLLoader(Main.class.getResource("Test.fxml"));
            AnchorPane root = (AnchorPane) loader.load();
            Scene scene = new Scene(root);
            scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
            stage.setTitle("Test");
            stage.setScene(scene);
            stage.show();
            
        } catch(Exception e) {
            e.printStackTrace();
        }
    }
    
    public static void main(String[] args) {
        launch(args);
    }
}

Controller:

package application;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.layout.AnchorPane;

public class Controller {
    @FXML
    private AnchorPane base;
    
    @FXML
    public void setBackgroundRed(ActionEvent event) {
        base.setStyle("-fx-background-color: red;");
    }
    @FXML
    public void setBackgroundGreen(ActionEvent event)   {
        base.setStyle("-fx-background-color: green;");
    }
}

That's what I made on SceneBuilder, and what the GUI looks like: SceneBuilder GUI

That's what I get instead, when I run the application: blank window

Edit: if I close and reopen SceneBuilder the GUI is ok. image

Answer 1

You're using Eclipse IDE right?

I think the issue is Eclipse. In fact, Eclipse by default doesn't refersh project resources automatically. Therefore, if you update and save your.fxml file from SceneBuilder, it goes out-of-sync inside the IDE, until you refresh the resources ( right click on Project folder > Refresh, or F5).

You can make Eclipse refresh resources automatically by selecting the option Refresh using native hooks or polling: Window > Preferences > General > Workspace > "refresh resources automatically".

That issue had been widely discussed in this thread .