JavaFX从文档控制器更改全局样式表

Question

I'm new to JavaFX and I'm currently working on a JavaFXML application. What I'm trying to do is find a way to change the global Stylesheet when I click on a button. My current code is this..

Main.Java

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

    public class CssChange extends Application {

    static FXMLDocumentController myControllerHandle;

    @Override
    public void start(Stage stage) throws Exception {
    FXMLLoader loader = new 
    FXMLLoader(getClass().getResource("CssChange.fxml"));
    Parent root = loader.load();

    myControllerHandle = (FXMLDocumentController)loader.getController();

    Scene scene = new Scene(root);

    stage.setScene(scene);
    stage.show();
}

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

Controller.java

    import java.io.IOException;
    import java.net.URL;
    import java.util.ResourceBundle;
    import javafx.event.ActionEvent;
    import javafx.fxml.FXML;
    import javafx.fxml.FXMLLoader;
    import javafx.fxml.Initializable;
    import javafx.scene.Parent;
    import javafx.scene.Scene;
    import javafx.scene.control.Button;
    import javafx.scene.control.Label;
    import javafx.scene.layout.AnchorPane;
    import javafx.scene.layout.Pane;

    public class FXMLDocumentController implements Initializable {

    @FXML
    private Label label;

@FXML
private Button button;

@FXML
private void CssChange(ActionEvent event) throws IOException{
    Parent root;
    root = (AnchorPane) FXMLLoader.load(getClass().getResource("CssChange.fxml"));
    System.out.println("You clicked me!");
    label.setText("Hello World!");
    String css = CssChange.class.getResource("login2.css").toExternalForm();
    root.getStylesheets().clear();
    root.getStylesheets().add(css);
    root.applyCss();
}

@Override
public void initialize(URL url, ResourceBundle rb) {
    // TODO
}    

}

FXML Document

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

    <?import java.lang.*?>
    <?import java.util.*?>
    <?import javafx.scene.*?>
    <?import javafx.scene.control.*?>
    <?import javafx.scene.layout.*?>
    <?import javafx.scene.text.Font?>

    <AnchorPane  prefHeight="800.0" prefWidth="480.0" 
       stylesheets="@Login.css" xmlns="http://javafx.com/javafx/8.0.111" 
       xmlns:fx="http://javafx.com/fxml/1" 
       fx:controller="csschange.FXMLDocumentController" fx:id="root">

<children>
  <Button layoutX="14.0" layoutY="25.0" mnemonicParsing="false" 
       onAction="#CssChange" text="CSS Change" fx:id="button">
     <font>
        <Font name="Arial Bold Italic" size="18.0" />
     </font>
  </Button>
  <Label layoutX="126" layoutY="120" minHeight="16" minWidth="69" 
       fx:id="label" />
  </children>
  </AnchorPane >

First CSS

    .root {
    -fx-background-color:
    linear-gradient(#000000 0%, #ffffff 100%);
    }

    .label {
    -fx-font-size: 12px;
    -fx-font-weight: bold;
    -fx-text-fill: #333333;
    -fx-effect: dropshadow( gaussian , rgba(255,255,255,0.5) , 0,0,0,1 );
    }

Second CSS

    .root {
    -fx-background-image: url("background.jpg");
    }

    .label {
    -fx-font-size: 12px;
    -fx-font-weight: bold;
    -fx-text-fill: #ffffff;
    -fx-effect: dropshadow( gaussian , rgba(255,255,255,0.5) , 0,0,0,1 );
    }

The code seems to work okay and when I click on the button I don't get any errors but, nothing happens. The second CSS does not seem to be called at all. I'd really appreciate any help I can get. Thank you in advance.

Answer 1

Have you tried to hide then show the stage (or your root pane)? Maybe actualize the display would change something...