Add text to two textfields with JButtons

Question

If my question wasn\'t very specific, here is what I am trying to do. I have a calculator that has two JTextFields, a JLabel (\"Answer = \"), and a JTextField for the answer.

Answer 1

Instead of using an ActionListener you can add an Action to the button. In this case you will want to extend TextAction because it has a method that allows you to get the last focused text component so you can insert the digit into that component. The code would be something like:

class AddDigit extends TextAction
{
    private String digit;

    public AddDigit(String digit)
    {
        super( digit );
        this.digit = digit;
    }

    public void actionPerformed(ActionEvent e)
    {
        JTextComponent component = getFocusedComponent();
        component.replaceSelection( digit );
    }
}