BackSpace not working in textfield

Question

Hi everybody!
I have a textfield that only lets enter numeric chars. It extends from JTextField.
The problem is that the Backspance key is not working. I see that is detected in the processKey Event but it does nothing.
I have seen some topics about that there is a bug in jdk1.3 and that a solution is using keyTyped instead. But I don't know how to do this.
May someone help me?
Thanxxxx

Answer 1

Hello,
i think the best way is to to use a custom PlainDocuments for your TextField:
import javax.swing.*;
import javax.swing.text.*;
public class NumberField extends JTextField {
     public NumberField(){
          setDocument(new PlainDocument(){
               public void insertString(int offset, String str, AttributeSet a)throws BadLocationException{
                    try{
                         Double.parseDouble(str);
                    }catch(NumberFormatException nfe){return;}
                    super.insertString(offset,str,a);
     public static void main(String[] args) {
          JFrame f=new JFrame();
          f.setBounds(0, 0, 100, 50);
          NumberField nf=new NumberField();
          f.getContentPane().add(nf);
          f.setVisible(true);
}Regards,
Tim