• Introducing listener :.addListener
• A property is an attribute of a class that you can read or write.
• Commonly, the property getter and setter simply read and write a field (place holder ).
• But the getter and setter may be engaged in advanced tasks like reading values from a database or sending out change notifications.

package javafxtemplate1;
// List to ListView1
//import java.awt.Image;

import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TextArea;
import javafx.scene.control.TextField;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

/**
*
* @author Manas9
*/
public class JavaFXTemplate1 extends Application {

Foo2 foo2 = new Foo2();
final TextArea txtArea = new TextArea();
Label label1 = new Label("Enter your name");

@Override
public void start(Stage primaryStage) throws Exception {

Group groot1 = new Group();
Group groot2 = new Group();
//
label1.setLayoutX(10);label1.setLayoutY(20);
TextField textField = new TextField ();
textField .setLayoutX(160);textField .setLayoutY(20);
textField.setPromptText("Enter Your Name");
textField.textProperty().addListener(new ChangeListener<String>() {
@Override
public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) {
//throw new UnsupportedOperationException("Not supported yet.");
foo2.setFoo2("@");
newValue += foo2.getFoo2();
foo2.setFoo2("$");
newValue += foo2.getFoo2();
label1.setText( newValue);
txtArea.appendText(newValue);
}
});

//textField.setOnKeyTyped(e -> handlekeyevent(e));
BorderPane bpane = new BorderPane();
groot1.getChildren().addAll(textField,label1);
groot2.getChildren().addAll(txtArea);
bpane.setCenter(groot2);
bpane.setTop(groot1);
//Scene scene = new Scene(groot, 350, 150);
Scene scene = new Scene(bpane, 350, 250);
primaryStage.setScene(scene);
primaryStage.setTitle("ObservableSet:: ChangeListener");
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}

}

Class Foo2
public class Foo2 {
public String strFoo2;
public String getFoo2(){
return strFoo2;
}
public void setFoo2(String param1)
{
strFoo2 = param1;
}
}