JavaFX: How The Button Is Created

This entry is part 4 of 55 in the series JavaFX

We look back at the same default example and see how the button is created and displayed in the scene of the interface.

There are basically 3 sequence of actions involved.

1. We first set up the button by putting the text “Click Me” inside the button.

btn.setText("Click Me");

2. We put the button inside a Stackpane by using Stackpane’s getChildren() and add() methods.

root.getChildren().add(btn);

3.  We display the button in the scene.

primaryStage.setScene(scene);

This really shows why many of us took a long time to master Java Swing or Microsoft Foundation Class.  It is easy to be overwhelmed by these sequence of procedures that we need to set up just to display a button!

Take note that in the program below, I have made a slight modification to display a different button text when it is clicked.

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package javafxapplication5;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

/**
 *
 * @author daryl
 */
public class JavaFXApplication5 extends Application {

    @Override
    public void start(Stage primaryStage) {
        Button btn = new Button();
        btn.setText("Click Me");
        btn.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent event) {
                btn.setText("Presto!");
            }
        });

        StackPane root = new StackPane();
        root.getChildren().add(btn);

        Scene scene = new Scene(root, 300, 250);

        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        launch(args);
    }

}

button

Series Navigation<< JavaFX: Structure of a JavaFX application
JavaFX: Common classes >>

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