help with gridbaglayout

[robertbob]

This is my first attempt at gridbaglayout so don't laugh :D I am trying to layout a simple calculator that has 2 text fields and 4 buttons to choose the operator. My problem is its not working :)

Here is what I want it to look like.


Here is what mine looks like:


Here is my code.

import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
public class Calculator extends JFrame {

    JButton add, subtract, multiply, divide;
    JTextField num1, num2;
    JLabel result, enter1, enter2;

    public Calculator() {
        setLayout(new GridBagLayout());
        GridBagConstraints c = new GridBagConstraints();

        enter1 = new JLabel("1st: ");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 0;
        add(enter1, c);

        num1 = new JTextField(10);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 1;
        c.gridy = 0;
        c.gridwidth = 3;
        add(num1, c);

        enter2 = new JLabel("2nd: ");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 1;
        add(enter2, c);

        num2 = new JTextField(10);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 1;
        c.gridy = 1;
        c.gridwidth = 3;
        add(num2, c);

        add = new JButton("+");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 2;
        add(add, c);

        subtract = new JButton("-");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 1;
        c.gridy = 2;
        add(subtract, c);

        multiply = new JButton("*");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 2;
        c.gridy = 2;
        add(multiply, c);

        divide = new JButton("/");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 3;
        c.gridy = 2;
        add(divide, c);

        result = new JLabel("");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 3;
        c.gridwidth = 4;
        add(result, c);
    }

    public static void main (String args[]) {
        Calculator gui = new Calculator();
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);
        gui.setSize(250,150);
        gui.setTitle("Calculator");
    }
}

[camickr]

The same constraint is used for every component. Since you never reset the gridwidth, I would guess the width of 3 is used for all components which is not what you want.

[robertbob]

OK... how do you go about resetting the grid width

[curmudgeon]

OK... how do you go about resetting the grid width

You might want to check out the GridBagConstraints API to see if there is a field with a name similar to gridWidth. You might get lucky!

[camickr]

OK... how do you go about resetting the grid width

Seriously?

What did you try? What problems did you have?

Your reply is time stamped 4 minutes after my suggestion. If you would even think about this for a minute I'm sure you can figure it out.

[curmudgeon]

On further review, you may wish to mix your layouts here. Consider using BorderLayout for the main JPanel, then adding the buttons to a JPanel that uses GridLayout(1, 0) (1 row, variable columns), and adding this button panel to the main panel BorderLayout.SOUTH. Then the JLabel/JTextField panel can use GridBagLayout and be added to the main JPanel BorderLayout.CENTER.