Javafx adding ActionListener to button

MertG picture MertG · Nov 23, 2016 · Viewed 25.2k times · Source
button.setOnAction(new EventHandler<ActionEvent>() {
    @Override public void handle(ActionEvent e) {
        label.setText("Accepted");
    }
});

In the code above we are defining what will happen when we press the button. This is all good but I wanna create new ActionListener and then add it to my button. Normally in JButton I can just add ActionListener like this:

button.addActionListener(someControllerClass.createButtonListener());

In code above createButtonListener() returns ActionListener.

My question is: What is the equivalent of JButton addActionListener ?

Answer

SSchuette picture SSchuette · Nov 23, 2016

If you want to e.g. reuse an EventHandler, define it like described in JavaFX Documentation as:

EventHandler<ActionEvent> buttonHandler = new EventHandler<ActionEvent>() {
    @Override
    public void handle(ActionEvent event) {
        label.setText("Accepted");
        event.consume();
    }
};

You can now add your defined buttonHandler to the onAction of your button via:

button.setOnAction(buttonHandler);

And citing from the documentation providing the remove option for completeness:

To remove an event handler that was registered by a convenience method, pass null to the convenience method, for example, node1.setOnMouseDragged(null).

Resulting for you in:

button.setOnAction(null)

The documentation furthermore provides some examples how to add handler for specific events - it's a good read.