Only numeric input in JTextField

Tue Oct 21, 2008 9:09 pm

Hi,

I'm trying to extend the JTextField class to a JNumField subclass in
which only numeric key-in would be accepted.
This is probably a very common problem, but I could not find a simple
solution to it yet.

I tried with a MaskFormatter, as explained here (see pjstroh's
message) but encountered problems when trying to compile the code.

Code:: http://forum.java.sun.com/thread.jspa?threadID=418002&messageID=1876495

So, I tried somehting different by checking the keyTyped key event.
But this does not work. Does someone know why ?

Here's some code from my JNumField class:

Code:: // *** Initialisation *** public void init() { setBackground(Color.white); addKeyListener(this); hasDecimalPoint = false; } // *** Implï¿½mentation de l'interface KeyListener *** public void keyTyped(KeyEvent ke) { char c = ke.getKeyChar(); if (!Character.isDigit(c)) ke.consume(); // prevent event propagation }

Thanks for any help.

Tue Oct 21, 2008 9:18 pm

Solved. The problem was that I adding the key listener from within the
init() function which is -I assume- called only for applets.
As my class is not an applet, the init() function was not called.
I can now catch key events as I moved addKeyListener(this) in the
class constructor.

Only numeric input in JTextField

Only numeric input in JTextField

Re: Only numeric input in JTextField

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