How do i update a JTextArea?

Question

Hey
I have a main GUI class where i can add one number to an ArrayList in an ohter class (Basket). After i added the number to the ArrayList
i can click a button to open anohter window (which is created in BasketGUI class) where a JTextArea are showing the numbers i have
added in the ArrayList.
But notthing is showing, i know the addition to the ArrayList works because it works with a System.out.println.
I have to post alot of code, so you could just skip the code and eksplain to me in generel how to update a JTextArea.
BasketGUI:
* Basket.java
* Created on 5. februar 2008, 15:29
package userclasses;
import java.util.ArrayList;
* @author  Lille mus
public class BasketGUI extends javax.swing.JFrame {
    private Basket basket;
    private Stock stock;
    private String newline = "\n";
    /** Creates new form Basket */
    public BasketGUI() {
        stock = new Stock();
        basket = new Basket();
        initComponents();
    public String showBasket(){
        ArrayList newBasket = basket.getArrayList();
        String returnBasket = "";
        for(Object item : newBasket){
            returnBasket += item+newline;
        return returnBasket;
    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {
        jLabel1 = new javax.swing.JLabel();
        jScrollPane1 = new javax.swing.JScrollPane();
        jTextArea1 = new javax.swing.JTextArea();
        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Indk?bskurv");
        jLabel1.setText("Indk?bskurv");
        jTextArea1.setColumns(20);
        jTextArea1.setRows(5);
        jTextArea1.setText(stock.printAllStockItems());
        jTextArea1.setText(showBasket());
        jScrollPane1.setViewportView(jTextArea1);
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(21, 21, 21)
                        .addComponent(jLabel1))
                    .addGroup(layout.createSequentialGroup()
                        .addContainerGap()
                        .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))
                .addContainerGap(224, Short.MAX_VALUE))
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jLabel1)
                .addGap(20, 20, 20)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(159, Short.MAX_VALUE))
        pack();
    }// </editor-fold>
     * @param args the command line arguments
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new BasketGUI().setVisible(true);
    // Variables declaration - do not modify
    private javax.swing.JLabel jLabel1;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JTextArea jTextArea1;
    // End of variables declaration
}This code is what happends when i click the button which adds a number to the ArrayList:
private void putInBasket(java.awt.event.ActionEvent evt) {                            
        //Integer itemId = Integer.parseInt(itemIdField.getText());
        basket.addItemToBasket(3);
        System.out.println(basket.showBasket());
    }Basket class:
* To change this template, choose Tools | Templates
* and open the template in the editor.
package userclasses;
import java.util.ArrayList;
* @author Jesper
public class Basket {
    private ArrayList<Integer> basket;
    private String returnBasket;
    private Stock stock;
    private String newline = "\n";
    public Basket(){
        basket = new ArrayList<Integer>();
        add4ItemsToBasket();
    public void addItemToBasket(int itemId){
        basket.add(itemId);
    public void add4ItemsToBasket(){
        addItemToBasket(1);
        addItemToBasket(2);
    public String showBasket(){
        for(Integer item : basket){
            returnBasket += item+newline;
        return returnBasket;
    public ArrayList getArrayList(){      
        return basket;
}Thank you!

Answer 1

okay... i cant figure out the logic in this. i have put this code into the BasketGUI class:
public void setBasketList(){
        basketListTextArea.append(basket.showBasket());
    }this function i call in my MainGUI here:
private void putInBasket(java.awt.event.ActionEvent evt) {                            
        //Integer itemId = Integer.parseInt(itemIdField.getText());
        basket.addItemToBasket(3);
        basketGUI.setBasketList();
        System.out.println(basket.showBasket());
    }What am i doing wrong?