keylistener not working after clicking button

user541597 picture user541597 · Nov 10, 2011 · Viewed 15.1k times · Source

I have a keylistener attached to my frame in java, i can detect key presses when I hit any key, a strange thing is happening however. My game is a minesweeper game, I have a restart button that basically clears the board and remines it. The weird thing is when I click the button with the mouse everything clears fine and the board is remined but the keylistener stops working. Even stranger I have a jmenuitem that basically does a automated click of the button. So its like restartbutton.doclick()

if i click the jmenuitem to restart it restarts fine clears everything and the keylistener still functions. I can even see the button being clicked. Any ideas why this could be happening?

Thanks

this is attached to my main frame. this is the listener that stops working after clicking the button.

frame.addKeyListener(new KeyListener(){


       public void keyReleased(KeyEvent e){


       }

       public void keyPressed(KeyEvent e){

       System.out.println("hey");
       int keycode = e.getKeyCode();

       if(e.isControlDown() & keycode==KeyEvent.VK_C){

      balh blah balh
       }

       }

       public void keyTyped(KeyEvent e){


       }

       });

Answer

Hovercraft Full Of Eels picture Hovercraft Full Of Eels · Nov 10, 2011

Suggestions:

  • Yours is a focus issue, where the KeyListener stops working because the container it is listening to has lost focus to the JButton.
  • One solution is to make the JButton not able to gain focus by calling setFocusable(false) on it.
  • But I recommend that you don't use a KeyListener at all if possible, but rather key bindings, since with bindings you don't have this issue and also it is a higher level construct.

Edit
Regarding:

what would be the best way to change that to a key binding?

Best would be to go through the Key Bindings tutorial and to implement the recommendations found there.