Problem With Text Fields!

[freshoreo]

I know that there a a few problems with this program, but the problem I want to fix first is that when I run this app, my text fields are not displayed. Instead, a very VERY small text field (less than 1 column) is displayed and I cannot type anything in. What am I doing wrong?

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
import java.text.*;
import java.lang.String;

public class ModifiedFutureValueApp
{
    public static void main(String[] args)
    {
        JFrame frame = new FutureValueFrame();
        frame.setVisible(true);
    }
}

class FutureValueFrame extends JFrame
{
    public FutureValueFrame()
    {
        setTitle("Future Value Calculator");
        centerWindow(this);
        setSize(267, 200);
        setResizable(false);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new FutureValuePanel();
        this.add(panel);
    }

    private void centerWindow(Window w)
    {
        Toolkit tk = Toolkit.getDefaultToolkit();
        Dimension d = tk.getScreenSize();
        setLocation((d.width-w.getWidth())/2, (d.height-w.getHeight())/2);
    }
}

class FutureValuePanel extends JPanel implements ActionListener
{
    private JTextField  paymentTextField,
                        rateTextField;
	 private JTextArea   futureValueTextArea;
	 private JScrollPane scrollPane;
    private JLabel      paymentLabel,
                        rateLabel,
                        yearsLabel,
                        futureValueLabel;
    private JButton     calculateButton,
                        exitButton;
	 private JComboBox   yearsComboBox;

    public FutureValuePanel()
    {
        setLayout(new GridBagLayout());

        // payment label
        paymentLabel = new JLabel("Monthly Payment:");
        add(paymentLabel, getConstraints(0,0,1,1, GridBagConstraints.EAST));

        // payment text field
        paymentTextField = new JTextField(15);
		  paymentTextField.setColumns(15);
        add(paymentTextField, getConstraints(1,0,1,1, GridBagConstraints.WEST));

        // rate label
        rateLabel = new JLabel("Yearly Interest Rate:");
        add(rateLabel, getConstraints(0,1,1,1, GridBagConstraints.EAST));

        // rate text field
        rateTextField = new JTextField(15);
		  rateTextField.setColumns(15);
        add(rateTextField, getConstraints(1,1,1,1, GridBagConstraints.WEST));

        // years label
		  yearsLabel = new JLabel("Number of Years:");
        add(yearsLabel, getConstraints(0,2,1,1, GridBagConstraints.EAST));
		  
		  //years combo box
		  String[] years = {"1", "2", "3", "4", "5", "6", "7", "8", "9", "10",
		  "11", "12", "13", "14", "15", "16", "17", "18", "19", "20" };
        yearsComboBox = new JComboBox(years);
		  yearsComboBox.setSelectedIndex(0);
		  yearsComboBox.addActionListener(this);
        add(yearsComboBox, getConstraints(1,2,1,1, GridBagConstraints.WEST));


        // future value label
        futureValueLabel = new JLabel("Future Value:");
        add(futureValueLabel, getConstraints(0,3,1,1, GridBagConstraints.EAST));

        // future value text field
		  JTextArea futureValueTextArea = new JTextArea(5, 15);
		  JScrollPane scrollPane = new JScrollPane(futureValueTextArea);
		  futureValueTextArea.setEditable(false);
		  futureValueTextArea.setColumns(15);
        add(scrollPane, getConstraints(1,3,1,1, GridBagConstraints.WEST));

        // calculate button
        calculateButton = new JButton("Calculate");
        calculateButton.addActionListener(this);
        add(calculateButton, getConstraints(1,4,1,1, GridBagConstraints.CENTER));

        // exit button
        exitButton = new JButton("Exit");
        exitButton.addActionListener(this);
        add(exitButton, getConstraints(2,4,1,1, GridBagConstraints.WEST));
		  
    }

    public void actionPerformed(ActionEvent e)
    {
        Object source = e.getSource();
        if (source == exitButton)
            System.exit(0);
        else if (source == calculateButton)
        {
            double payment = Double.parseDouble(paymentTextField.getText());
            double rate = Double.parseDouble(rateTextField.getText());
				int years = yearsComboBox.getSelectedIndex();
            double futureValue = FinancialCalculations.calculateFutureValue(
                payment, rate, years);
            NumberFormat currency = NumberFormat.getCurrencyInstance();
            futureValueTextArea.setText(currency.format(futureValue));
        }
    }
	 private GridBagConstraints getConstraints(int gridx, int gridy, int gridwidth
	 , int gridheight, int anchor)
	 {
	 	GridBagConstraints c = new GridBagConstraints();
		c.insets = new Insets(5, 5, 5, 5);
		c.ipadx = 0;
		c.ipady = 0;
		c.gridx = gridx;
		c.gridy = gridy;
		c.gridwidth = gridwidth;
		c.gridheight = gridheight;
		c.anchor = anchor;
		return c;
	 }
}

[newmember]

i face the same problem, i dont know the reason.

but i prefer this
rateTextField.setPrefferedSize( new Dimension(100,20)) ;

and for centering the form ,

setLocationRelativeto( null ) ; after setting the size of the form

[Norm]

I changed the setSize() to 400,400 and got the components to display. Then you need to adjust it and the constraints to what you want.

Also the this.add() should be getContentPane().add()

[freshoreo]

Wow, I knew it had to be something simple like that! Thank you so much!