为什么组件没有出现在屏幕中央？

Question

I need the components of the scene to be placed in the middle of the window when the user runs the program and this is not the case. How may I solve this? The scene only seems to appear at the right but not at the center. I attached an image of the output I am getting.

public class WelcomeScene extends Scene{
    public WelcomeScene(Pane pane, double width, double height){
        super(pane,width,height);
        setFill(Color.PINK);
        VBox vbox = new VBox();
        Label label = new Label("Welcome to the typing\n practice world");
        label.setFont(new Font("Cambria", 32));
        label.setStyle("-fx-text-alignment: center;");
        label.setTextFill(Color.RED);
        label.centerShapeProperty().bind(pane.centerShapeProperty());

        HBox hbox = new HBox();
        Button StartTypingBtn = new Button("Start typing");
        Button showFingurePosition = new Button("Check fingures prositions");
        Button checkImprovement = new Button("Check Improvement");
        hbox.setSpacing(10);
        hbox.setAlignment(Pos.CENTER);

        hbox.getChildren().add(StartTypingBtn);
        hbox.getChildren().add(showFingurePosition);
        hbox.getChildren().add(checkImprovement);

        vbox.getChildren().addAll(label, new 
            ImageView("photos/hands_email.gif"),
                hbox);
        vbox.setAlignment(Pos.CENTER);
        pane.getChildren().add(vbox);
        pane.setCenterShape(true);
    }
}

public class Touch extends Application {
    @Override
    public void start(Stage primaryStage) throws Exception {
        Rectangle2D screenBounds = Screen.getPrimary().getVisualBounds();
        primaryStage.setScene(new WelcomeScene(new Pane(),
                screenBounds.getWidth(),screenBounds.getHeight()));
        primaryStage.show();
    }
    public static void main(String [] args) {
        Application.launch(args);
    }
}

enter image description here

Answer 1

One thing you can do is change Pane to StackPane .

Touch

primaryStage.setScene(new WelcomeScene(new StackPane(),
            screenBounds.getWidth(), screenBounds.getHeight()));

WelcomeScene

 public WelcomeScene(StackPane pane, double width, double height)

Full code

Touch

import javafx.application.Application;
import javafx.geometry.Rectangle2D;
import javafx.scene.layout.StackPane;
import javafx.stage.Screen;
import javafx.stage.Stage;

public class Touch extends Application
{
    @Override
    public void start(Stage primaryStage) throws Exception
    {
        Rectangle2D screenBounds = Screen.getPrimary().getVisualBounds();
        primaryStage.setScene(new WelcomeScene(new StackPane(),
                screenBounds.getWidth(), screenBounds.getHeight()));
        primaryStage.show();
    }

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

WelcomeScene

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.HBox;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;

public class WelcomeScene extends Scene
{
    public WelcomeScene(StackPane pane, double width, double height)
    {
        super(pane, width, height);
        try {
            setFill(Color.PINK);
            VBox vbox = new VBox();
            Label label = new Label("Welcome to the typing\n practice world");
            label.setFont(new Font("Cambria", 32));
            label.setStyle("-fx-text-alignment: center;");
            label.setTextFill(Color.RED);
            label.centerShapeProperty().bind(pane.centerShapeProperty());

            HBox hbox = new HBox();
            Button StartTypingBtn = new Button("Start typing");
            Button showFingurePosition = new Button("Check fingures prositions");
            Button checkImprovement = new Button("Check Improvement");
            hbox.setSpacing(10);
            hbox.setAlignment(Pos.CENTER);

            hbox.getChildren().add(StartTypingBtn);
            hbox.getChildren().add(showFingurePosition);
            hbox.getChildren().add(checkImprovement);

            vbox.getChildren().addAll(label, new ImageView(new Image(new FileInputStream("photos/hands_email.gif"))), hbox);
            vbox.setAlignment(Pos.CENTER);
            pane.getChildren().add(vbox);
            pane.setCenterShape(true);
        }
        catch (FileNotFoundException ex) {
            ex.printStackTrace();
        }
    }
}

Answer 2

One possability could be that your vbox takes only the space it needs for the image and the hbox.
Try to set the hight and wide of the vbox to max balue so it takes the whole space.