JavaFX TextField text validation

Question

I have a listener applied to my field:

nameTextField.addEventHandler(KeyEvent.KEY_TYPED, fieldChangeListener(50));

Event handler:<

Answer 1

If you want to do input validation when the text is changing, you could use a listener on the textProperty of the TextField:

textField.textProperty().addListener((observable, oldValue, newValue) ->
    System.out.println("Input Validation"));

To detect when Enter is pressed, you can use the onActionProperty

textField.setOnAction(event -> System.out.println("Enter pressed: Word Check"));

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If you want to prevent the user to input characters that fails the validation logic, then rather than listening to the textProperty˙, you can use a TextFormatter (this TextField only accept integers):

textField.setTextFormatter(new TextFormatter<>(change ->
         (change.getControlNewText().matches("([1-9][0-9]*)?")) ? change : null));