How do you make ENTER trigger onAction for JavaFX globally?

Question

I saw in another question that this was the solution for when you want to press enter to trigger onAction

    btn.defaultButtonProperty().bind(item_btn.focusedProperty());

Is there a way to do this globally for all buttons, or will I have to initialize each component and go through every button and bind it this way?

Not sure if you can have multiple default buttons. In the Javadoc it sounds like ther's supposed to be at most one such button(at least judging based on the use of singular)... — fabian

James_D James_D · Accepted Answer · 2020-06-17T22:15:28

You can register an event handler with the scene, and check if a button has focus:

Scene scene = ... ;
scene.addEventHandler(KeyEvent.KEY_PRESSED, e -> {
    if (e.getCode() == KeyCode.ENTER) {
        if (scene.getFocusOwner() instanceof Button) {
            Button button = (Button)scene.getFocusOwner();
            button.fire();
        }
    }
});

Demo:

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;

public class App extends Application {

    @Override
    public void start(Stage stage) {

        HBox controls = new HBox(5);
        controls.getChildren().add(new TextField());
        for (int i = 1 ; i <=5 ; i++) {
            String text = "Button "+i ;
            Button button = new Button(text);
            button.setOnAction(e -> System.out.println(text));
            controls.getChildren().add(button);
        }

        Scene scene = new Scene(controls, 600, 400);
        scene.addEventHandler(KeyEvent.KEY_PRESSED, e -> {
            if (e.getCode() == KeyCode.ENTER) {
                if (scene.getFocusOwner() instanceof Button) {
                    Button button = (Button) scene.getFocusOwner();
                    button.fire();
                }
            }
        });


        stage.setScene(scene);
        stage.show();
    }

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

}

How do you make ENTER trigger onAction for JavaFX globally?

1 Answers