Concept explainers
Explanation of Solution
Event handler:
- The event handler is nothing but an object that responds to the events.
- A particular method in the event handler is called if an event source is connected to the event handler. The object of the event is passed as the argument to that method.
- This process is known as event firing.
- The event handler class should implement the “EventHandler” interface.
- This interface is in the package “javafx.event”.
Step 1: Declare a class named “ButtonClickHandler”.
Step 2: Declare a method named “handle”.
Step 3: Set the text for “outputLabel” as “Hello World”
Event handler class:
//Event handler class
class ButtonClickHandler implements EventHandler <ActionEvent>
{
//Overrides handle class
@Override
public void handle(ActionEvent event)
{
//Set the text
outputLabel.setText("Hello World");
}
}
Example program:
The below program demonstrates the Event handler class.
//Import required packages
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.geometry.Insets;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.layout.VBox;
import javafx.scene.control.Label;
import javafx.scene.control.Button;
//Declare the main class
public class Example extends Application
{
//Create a label
private Label outputLabel;
//Declare the main method
public static void main(String[] args)
{
// Launch the application...
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