JavaFX KeyEvent returns KeyCode.UNDEFINED

问题:

I created a simple JavaFX application that receives input from the user in a TextField. I attached the KeyTyped event from SceneBuilder to the controller. My function looks like this:

@FXML private void keyTyped(KeyEvent event) {
    System.out.println(event.getCode().equals(KeyCode.ENTER));
}

This function always prints out UNDEFINED when I type the enter key. Any ideas on how to fix this? Other letters I type seem to have the same problem as well.

回答1:

KeyTyped is a special event. It doesn't have KeyCode but has character set instead.

See example for letter 'a':

KeyEvent [source = TextField[id=null, styleClass=text-input text-field], 
target = TextField[id=null, styleClass=text-input text-field], eventType = KEY_TYPED, consumed = false, 
character = a, text = , code = UNDEFINED]

and javadoc: http://docs.oracle.com/javafx/2/api/javafx/scene/input/KeyEvent.html#getCode()

The key code associated with the key in this key pressed or key released event. For key typed events, code is always KeyCode.UNDEFINED.