Max010 schrieb:

[Code snippet]

Hi!
To be honest, I think your solution makes it more complicated than it
is. You really should think about using a MouseListener to determine
which component has the focus. I would advice you to use such low-level
listeners (like MouseListener) only if you really need them.
For example: If you use a FocusListener you also can handle a
focuschange if someone used the tab-key to change the focus, but also
you recognize the focuschange, if the mouse is clicked.

I wrote a little example. You can have a look at it, and perhaps it
helps... (although it is not perfect...)
It demonstrates, you do not need an extra listener for every button with
a number on it and it uses a FocusListener instead of a MouseListener.

import javax.swing.*;
import java.awt.GridLayout;
import java.awt.BorderLayout;
import java.awt.event.FocusListener;
import java.awt.event.FocusEvent;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

public class Calculator extends JFrame {

    JTextField lastFocus;
    JButton[] buttons;
    JButton enter;
   
    public Calculator() {
        super();
        setTitle("Calculator Example");
        JPanel textFieldPanel = new JPanel();
        JTextField textField1 = new JTextField(10);
        JTextField textField2 = new JTextField(10);
        MyFocusListener focusListener = new MyFocusListener();
        textField1.addFocusListener(focusListener);
        textField2.addFocusListener(focusListener);
        textFieldPanel.add(textField1);
        textFieldPanel.add(textField2);
       
        ButtonListener numberListener = new ButtonListener();
       
        buttons = new JButton[10];
        for (int i=0;i<buttons.length;i++) {
            buttons[i] = new JButton(""+i);
            buttons[i].addActionListener(numberListener);
        }
        enter = new JButton("Enter");
        enter.addActionListener(new EnterButtonListener());
       
        JPanel buttonPanel = new JPanel();
        buttonPanel.setLayout(new GridLayout(0,3));
        buttonPanel.add(buttons[7]);
        buttonPanel.add(buttons[8]);
        buttonPanel.add(buttons[9]);
        buttonPanel.add(buttons[4]);
        buttonPanel.add(buttons[5]);
        buttonPanel.add(buttons[6]);
        buttonPanel.add(buttons[1]);
        buttonPanel.add(buttons[2]);
        buttonPanel.add(buttons[3]);
        buttonPanel.add(buttons[0]);
        buttonPanel.add(enter);
       
        add(textFieldPanel,BorderLayout.NORTH);
        add(buttonPanel,BorderLayout.CENTER);
        lastFocus = textField1;
        setVisible(true);
        pack();
    }
   
    public static void main(String[] args) {
        Calculator calc = new Calculator();
    }
   
    private class MyFocusListener implements FocusListener {
        public void focusGained(FocusEvent e) {
            lastFocus = (JTextField) e.getSource();
        }
        public void focusLost(FocusEvent e) {       
        }
    }
    private class ButtonListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            String text = lastFocus.getText();
            text = text + e.getActionCommand();
            lastFocus.setText(text);
        }
    }
    private class EnterButtonListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            // do something...
        }
    }
}

hope that helps!
bye, Ralf

Well, if it does what you want it to, it's a working solution. You could
"improve" the code a bit by using the object oriented nature of java to
reduce code duplication etc. Have a look at the code below i hacked together
to do what you want (i think).

It reduces the code duplication by having all the buttons use the same event
routine. Also the two textfields use the same event method and it uses the
JTextField object stored in a variable to reference the correct field which
means you don't have to build an if-tree anymore.

[code]

import java.awt.event.MouseEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class FieldInput {

   JTextField currentField = null;

   public FieldInput() {

       JFrame mainFrame = new JFrame("Field Input Test");
       mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
       JPanel mainPanel = new JPanel();

       mainPanel.add(new JLabel("Table :"));
       JTextField tableField = createTextField();
       mainPanel.add(tableField);
       mainPanel.add(new JLabel("Guest :"));
       JTextField guestField = createTextField();
       mainPanel.add(guestField);

       JPanel buttonPanel = new JPanel();
       for (int x = 0; x < 10; x++) {
           mainPanel.add(newButton(x));
       }

       currentField = tableField;

       mainFrame.setContentPane(mainPanel);
       mainFrame.pack();
       mainFrame.setVisible(true);
   }

   private JTextField createTextField() {
       JTextField field = new JTextField();
       field.setColumns(15);
       field.addMouseListener(new java.awt.event.MouseAdapter() {
           public void mouseClicked(MouseEvent e) {
               fieldMouseClicked(e);
           }
       });
       return(field);
   }

   private JButton newButton(int x) {
       String buttonText = Integer.toString(x);
       JButton button = new JButton(buttonText);
       button.addMouseListener(new java.awt.event.MouseAdapter() {
           public void mouseClicked(MouseEvent e) {
               buttonMouseClicked(e);
           }
       });
       return(button);
   }

   private void fieldMouseClicked(MouseEvent e) {
       currentField = (JTextField)e.getSource();
   }

   private void buttonMouseClicked(MouseEvent e) {
       JButton button = (JButton)e.getSource();
       String buttonText = button.getText();
       currentField.setText(currentField.getText() + buttonText);
   }

   public static void main(String[] args) {
       FieldInput inputPanel = new FieldInput();
   }

}

[/code]

Happy Coding,
Guido