Popup Class Usage in JavaFX

public class test extends Application{ Stage primaryStage; @Override public void start(final Stage stage) throws Exception { primaryStage = stage; Button showPopUp = new Button("Pop Up"); final TextField name = new TextField(); VBox vBox = new VBox(); vBox.getChildren().add(name); vBox.getChildren().add(showPopUp); final Label hello = new Label(); final TextField name2 = new TextField(); Button ok = new Button("ok"); Button cencel = new Button("cancel"); VBox popUpVBox = new VBox(); popUpVBox.getChildren().add(hello); popUpVBox.getChildren().add(name2); popUpVBox.getChildren().add(ok); popUpVBox.getChildren().add(cencel); final Popup popup = new Popup(); popup.setAutoFix(false); popup.setHideOnEscape(true); popup.getContent().addAll(popUpVBox); popup.setX(250); popup.setY(175); ok.setOnAction(new EventHandler<ActionEvent>() { @Override public void handle(ActionEvent t) { name.setText(name2.getText()); } }); cencel.setOnAction(new EventHandler<ActionEvent>() { @Override public void handle(ActionEvent t) { popup.hide(); } }); showPopUp.setOnAction(new EventHandler<ActionEvent>() { @Override public void handle(ActionEvent t) { if (popup.isShowing()) { popup.hide(); } else { hello.setText("hello.."+name.getText()); popup.show(stage); } } }); Scene scene = new Scene(vBox); primaryStage.setScene(scene); primaryStage.setWidth(200); primaryStage.setHeight(200); primaryStage.show(); } }