Javatar4ever Javatar4ever - 23 days ago 7
Java Question

Caret (^) does not register immediately. Java key listener

I am currently building a calculator in Java and have started implementing
a key listener. It works very well, but when I try to type the caret symbol (^) it doesn't register immediately. You have to press another key first to make it appear.

I guess the reason for this is that it uses the same behavior as when you try to type a caret
in a regular text document. But is there any way to come around this behavior?

If it helps, here is my code to handle the KeyEvents:

@Override
public void handle(KeyEvent ke) {
String key = ke.getCharacter();

if (key.matches("[0-9*/+-=.()^%]")) {
controller.getButton(key).fire();
}
}


EDIT: Found a workaround. The problem as Eli Sadoff mentioned is that my caret is a dead key on my keyboard. Since my binding for the caret is " shift+¨ ", I was able to solve it like this:

@Override
public void handle(KeyEvent ke) {
String key = ke.getCharacter();

if (ke.isShiftDown() && ke.getCode() == KeyCode.DEAD_DIAERESIS) {
controller.getButton("^").fire();
}

else if (key.matches("[0-9*/+-=.()%]")) {
controller.getButton(key).fire();
}
}

Answer

The issue is that the input keyboard layout you are using on your computer treats ^ as a dead key, as it is a combining diacritic. The way to fix this would be to change your input keyboard layout to a keyboard that does not treat ^ as a combining diacritic. This can be tested by typing ^ + e and seeing if it results in ê or ^e.