ActionListeners and ItemListener

Hi
I'm using some ItemListener to detect when things are selected from a list but require a button to open a new GUI window. However, when i try and compile, the compiler says i can't use ActionListeners and ItemListeners in the same class. Is this true? Any ways i can get around it?
Cheers

implements ItemListener and ActionListener
gives the following error messages:
ListTest.java:6: '{' expected
public class ListTest extends GUIFrame implements ItemListener and ActionListener
^
ListTest.java:100: '}' expected
^
ListTest.java:6: ListTest should be declared abstract; it does not define itemStateChanged(java.awt.event.ItemEvent) in ListTest
public class ListTest extends GUIFrame implements ItemListener and ActionListener
anymore ideas?

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How to use ActionListener and ItemListener in the same class

Why can't I use both ActionListener and ItemListener in the same Class?
I want to use a drop down list and an entry box on the same form.
How? I'm having trouble compling......
Thanks!
CODE:
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
public class Disp extends Applet implements ActionListener, ItemListener
{ TextField entry=new TextField(7);
Button Enter=new Button("Enter");
public void init()
add(entry);
add(Enter);
entry.addActionListener(this);
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String answer=entry.getText();

Simply get your Applet to implement both ActionListener and ItemListener.
public class MyApplet extends Applet implements ActionListener, ItemListener
public void init()
    itemWidget.addItemListener(this):
    actionWidget.addActionListener(this);
public void actionPerformed(ActionEvent e)
    System.out.println("ACTION PERFORMED!");
public void itemStateChanged(ItemEvent e)
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ActionListeners and ActionEvents

Alright guys I am building myself a GUI and am using ActionListeners and ActionEvents however I'm not exactly sure what these 2 things do. I know they are used for buttons seeing as all of my buttons implement them but what specifically do they do. How does the ActionListener link to the ActionEvent???

Check this out:
http://java.sun.com/docs/books/tutorial/uiswing/learn/index.html
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ActionListeners and scope

Hello,
I have been trying to get my action listener to work so that it outputs the volume that is passed into. I want to limit the volume between 0 and 15 or there abouts. I have been reading books upon books to try and figure out where i have gone wrong but i just can't seem to figure it.
Here is my code below. any help would be appreciated
import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;
* Gareth Leah
class volumeControl extends JFrame {
public class VolumeSensor {
private int lowVolume;
private int maxVolume;
private int volume;
//CONSTRUCTORS
public VolumeSensor() {
this(null,0, 15, 10);
public VolumeSensor(String n, int lowVolume, int maxVolume, int volume) {
this.lowVolume = lowVolume;
this.maxVolume = maxVolume;
this.volume = volume;
//methods
public int getlowVolume() {
return lowVolume;
public void setlowVolume(int lowVolume) {
this.lowVolume = lowVolume;
public int getmaxVolume() {
return maxVolume;
public void setmaxVolume(int maxVolume) {
this.maxVolume = maxVolume;
public int getVolume() {
return volume;
public void setVolume(int volume) {
this.volume = volume;
public boolean Mute(){
return true;
public volumeControl() {
this.setTitle("Volume Controller");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel p = new JPanel();
//--------Volume Label------------------------------
JLabel Label = new JLabel("Volume");
Label.setForeground(Color.black);
Font font = new Font("Serif", Font.PLAIN, 15);
Label.setFont(font);
//--------Mute------------------------------
JCheckBox Mute = new JCheckBox("Mute");
Mute.setSelected(false);
p = new JPanel();
p.add(Mute);
this.add(p, BorderLayout.SOUTH);
//--------Volume------------------------------
final JSlider volume = new JSlider(0,15,7);
volume.setOrientation(SwingConstants.VERTICAL);
volume.setToolTipText("Volume Control");
volume.setPaintTicks(true);
volume.setPaintLabels(true);
//------------------Set it out---------------
p.setLayout(new BoxLayout(p, BoxLayout.PAGE_AXIS));
p.setBorder(BorderFactory.createEmptyBorder(0, 10, 10, 10));
p.add(Box.createHorizontalGlue());
p.add(Label);
p.add(volume,BorderLayout.CENTER);
p.add(Box.createRigidArea(new Dimension(10, 0)));
p.add(Mute);
//actionlistener
volume.addChangeListener(new ChangeListener() {
+public void stateChanged(ChangeEvent slider) {+
JSlider volume = (JSlider)slider.getVolume() ;
if (slider.volume>15)
System.out.println(volume);
+ +//int volume = (int)volume.getVolume();++
++// if (volume == 0) {++
++// if (lowVolume) Mute(false);++
+} else {+
System.out.println(volume);
+}+
+});+
this.pack();
this.setVisible(true);
/* Test */
public static void main(String[] arg) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
volumeControl v = new volumeControl();

Thanks again! i feel like im starting to get the hang of this. I have changed my program to:
import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;
* Gareth Leah
class volumeControl extends JFrame {
public class VolumeSensor {
    public boolean Mute(){
        return true;
        public volumeControl() {
        this.setTitle("Volume Controller");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel p = new JPanel();
         //--------Volume Label------------------------------
        JLabel Label = new JLabel("Volume");
        Label.setForeground(Color.black);
        Font font = new Font("Serif", Font.PLAIN, 15);
        Label.setFont(font);
         //--------Mute------------------------------
        JCheckBox Mute = new JCheckBox("Mute");
        Mute.setSelected(false);
        p = new JPanel();
        p.add(Mute);
        this.add(p, BorderLayout.SOUTH);
        //--------Volume------------------------------
        final JSlider volume = new JSlider(0,15,7);
        volume.setOrientation(SwingConstants.VERTICAL);
        volume.setToolTipText("Volume Control");
        volume.setPaintTicks(true);
        volume.setPaintLabels(true);
        //------------------Set it out---------------
        p.setLayout(new BoxLayout(p, BoxLayout.PAGE_AXIS));
        p.setBorder(BorderFactory.createEmptyBorder(0, 10, 10, 10));
        p.add(Box.createHorizontalGlue());
        p.add(Label);
        p.add(volume,BorderLayout.CENTER);
        p.add(Box.createRigidArea(new Dimension(10, 0)));
        p.add(Mute);
        //actionlistener
       volume.addChangeListener(new ChangeListener() {
        public void stateChanged(ChangeEvent e) {
        int volumeLevel = volume.getValue();
        if (volumeLevel<=15 || volumeLevel>=1)
            System.out.println(volumeLevel);
        this.pack();
        this.setVisible(true);
    /* Test */
    public static void main(String[] arg) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                volumeControl v = new volumeControl();
and i keep getting this compile error:
compile:
run:
2009-07-28 13:14:24.975 java[23021] CFLog (0): CFMessagePort: bootstrap_register(): failed 1103 (0x44f), port = 0xe903, name = 'java.ServiceProvider'
See /usr/include/servers/bootstrap_defs.h for the error codes.
2009-07-28 13:14:24.975 java[23021] CFLog (99): CFMessagePortCreateLocal(): failed to name Mach port (java.ServiceProvider)
i'm really not sure how to fix the compile error but i think im getting this jbox ok!

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@Entity
@Table(name = "PARCEL")
@Inheritance
@DiscriminatorColumn(name = "USER")
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public Parcel() {
@Id
@Column(name = "PARCELPIN", nullable = false)
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Hello Meeraj_Kanaparthi
Thanks for helping i m giving u the code i have tried.
Plz help me on this...
Thanks........
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import java.awt.event.*;
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Hi!
I have been working on this simple Java 1.3.1 program for three days now and cannot figure out what I am doing wrong. If anyone has done the "Building an Application" tutorial in the New to Java Programming Center, you might recognize the code. I am trying to set up a frame with panels first using the BorderLayout and then the FlowLayout within each section of the BorderLayout. It will have textfields and checkboxes. I am working on the code to retrieve the user input from the text boxes and also to determine which checkbox the user has checked. Here is my code: (ignore my irrelivent comments!)
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.awt.event.*;
import java.awt.Color.*;
import java.awt.Image.*;
//Header Comment for a Routine/Method
//This method gathers the input text supplied by the user from five text fields on the Current
//Purchase tab of the tabbed pane of the MPGLog.java program. The way it gathers the text
//depends on the current processing state, which it retrieves on its own. It saves the text to
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public class CollectTextInput extends JPanel implements ActionListener
{ // Begin class
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     // These are the text fields
     private JTextField currentMileage;
     private JTextField numofGallonsBought;
     private JTextField dateofPurchase;
     private JTextField pricePerGallon;
     private JTextField gasBrand;
     // Declaring the Labels to go with each TextField
     private JLabel lblcurrentMileage;
     private JLabel lblnumofGallonsBought;
     private JLabel lbldateofPurchase;
     private JLabel lblpricePerGallon;
     private JLabel lblgasBrand;
     // Declaring the Checkboxes for the types of gas bought
     private JCheckBox chbxReg;
     private JCheckBox chbxSuper;
     private JCheckBox chbxUltra;
     private JCheckBox chbxOther;
     private JCheckBox chbxHigher;
     private JCheckBox chbxLower;
     // Declaring the Buttons and images needed
     private JButton enter;
     private JButton edit;
     //private JButton report; //Will be used later
     private JLabel bluecar;          //Used with the ImageIcon to create CRV image
     private JPanel carimage;     //Used in buildImagePanel method
     private JPanel datum;          //Used in buildDatumPanel method
     private JPanel gasgrade;     //Used in buildGasTypePanel method.
     //Declaring the Panels that need to be built and added
     //to the border layout of this panel.
     //private JPanel panlimages;
     //private JPanel panltextinputs;
     //private JPanel panlchkBoxes;
     // Class to handle functionality of checkboxes
     ItemListener handler = new CheckBoxHandler();
     // This is where you add the constructor for the class - I THINK!!
     public CollectTextInput()
     { // Opens collectTextInput constructor
          // Must set layout for collectTextInput here
          // Choosing a BorderLayout because we simply want to
          // add panels to the North, Center and South borders, which, by
          // default, will fill the layout with the three panels
          // we are creating
          setLayout(new BorderLayout());
          //Initialize the objects in the constructor of the class.
          //Initialize the textfields
          currentMileage = new JTextField();
          numofGallonsBought = new JTextField();
          dateofPurchase = new JTextField();
          pricePerGallon = new JTextField();
          gasBrand = new JTextField();
          // Initialize the labels that go with each TextField
          lblcurrentMileage = new JLabel("Enter the mileage at the time of gas purchase: ");
          lblnumofGallonsBought = new JLabel("Enter the number of gallons of gas bought: ");
          lbldateofPurchase = new JLabel("Enter the date of the purchase: ");
          lblpricePerGallon = new JLabel("Enter the price per gallon you paid for the gas: ");
          lblgasBrand = new JLabel("Enter the brand name of the gas: ");
          //Initialize the labels for the checkboxes.
          chbxReg = new JCheckBox("Regular ", true);
          chbxSuper = new JCheckBox("Super ");
          chbxUltra = new JCheckBox("Ultra ");
          chbxOther = new JCheckBox("Other: (Choose one from below) ");
          chbxHigher = new JCheckBox("Higher than Ultra ");
          chbxLower = new JCheckBox("Lower than Ultra ");
          //Initialize the buttons that go on the panel.
          enter = new JButton("Save Data");
          edit = new JButton("Edit Data");
          //Initialize the image that oges on the panel.
          bluecar = new JLabel("2002 Honda CR-V", new ImageIcon("CRVBlue.jpg"),JLabel.CENTER);
          // Now bring it all together by calling the other methods
          // that build the other panels and menu.
          buildImagePanel();
          buildDatumPanel();
          buildGasTypePanel();
          // Once the methods above build the panels, this call to add
          // them will add the panels to the main panel's border
          // layout manager.
          add(datum, BorderLayout.NORTH);
          add(carimage, BorderLayout.EAST);
          add(gasgrade, BorderLayout.CENTER);
     } // Ends the constructor.
        // This method creates a panel called images that holds the car image.
     public void buildImagePanel();
     { // Opens buildImagePanel.
          // First, create the Panel
          carimage = new JPanel();
          //Second, set the color and layout.
          carimage.setBackground(Color.white);
          carimage.setLayout(new FlowLayout());
          // Third, add the image to the panel.
          carimage.add(bluecar);
     }// Closes buildImagePanel
     //This method creates a panel called datum that holds the text input.
     public void buildDatumPanel();
     { //Opens buildDatumPanel
          // First, create the Panel.
          datum = new JPanel();
          //Second, set the background color and layout.
          datum.setBackground(Color.white);
          datum.setLayout(new GridLayout(2, 4, 20, 20));
          //Third, add the textfields and text labels to the panel.
          datum.add(lblcurrentMileage);
          datum.add(currentMileage);
          datum.add(lblnumofGallonsBought);
          datum.add(numofGallonsBought);
          datum.add(lbldateofPurchase);
          datum.add(dateofPurchase);
          datum.add(lblpricePerGallon);
          datum.add(pricePerGallon);
          datum.add(lblgasBrand);
          datum.add(gasBrand);
          //Optionally - Fourth -set a border around the panel, including
          // a title.
          datum.setBorder(BorderFactory.createTitledBorder("Per Purchase Information"));
          //Fifth - Add listeners to each text field to be able to
          // know when data is input into them.
          currentMileage.addActionListener(this);
          numofGallonsBought.addActionListener(this);
          dateofPurchase.addActionListener(this);
          pricePerGallon.addActionListener(this);
          gasBrand.addActionListener(this);
     }// Closes buildDatumPanel
     // This method builds a panel called gasTypePanel that holds the checkboxes.
     public void buildGasTypePanel()
     { // Opens buildGasTypePanel method
          // First, create the panel.
          gasgrade = new JPanel();
          // Second, set its background color and its layout.
          gasgrade.setBackground(Color.white);
          gasgrade.setLayout(new GridLayout(5, 1, 10, 20));
          // Third, add all the checkboxes to the panel.
          gasgrade.add(chbxReg);
          gasgrade.add(chbxSuper);
          gasgrade.add(chbxUltra);
          gasgrade.add(chbxOther);
          gasgrade.add(chbxHigher);
          gasgrade.add(chbxLower);
          //Optionally, - Fourth - set a border around the panel, including
          // a title.
          gasgrade.setBorder(BorderFactory.createTitledBorder("Gas Type Information"));
          // Fifth - CheckBoxes require a CheckBox Handler.
          // This is a method created separately
          // outside of the method where the checkboxes are added to
          // the panel or where the checkboxes are even created.
          // This method (CheckBox Handler) implements and ItemListener
          // and is a self-contained method all on its own. See
          // the CheckBox Handler methods following the
          // actionPerformed method which follows.-SLM
     } // Closes the buildGasTypePanel method
// Create the functionality to capture and react to an event
//   for the checkboxes when they are checked by the user and
//   the text fields to know when text is entered. Also to react to the
//   Enter button being pushed and the edit button being pushed.
public void actionPerformed(ActionEvent evt)
{ // Opens actionPerformed method.
     if((evt.getSource() == currentMileage) || (evt.getSource() == enter))
          { // Opens if statement.
            // Retrieves the text from the currentMileage text field
            // and assigns it to the variable currentMileageText of
            // type String.
            String currentMileageText = currentMileage.getText();
            lblcurrentMileage.setText("Current Mileage is:    " + currentMileageText);
            // After printing text to JLabel, hide the text field.
            currentMileage.setVisible(false);
       } // Ends if statement.
      if((evt.getSource() == numofGallonsBought) || (evt.getSource() == enter))
          { // Opens if statement.
            // Retrieves the text from the numofGallonsBought text field
            // and assigns it to the variable numofGallonsBoughtText of
            // type String.
            String numofGallonsBoughtText = numofGallonsBought.getText();
            lblnumofGallonsBought.setText("The number of gallons of gas bought is:    " + numofGallonsBoughtText);
            // After printing text to JLabel, hide the text field.
            numofGallonsBought.setVisible(false);
       } // Ends if statement.
       if((evt.getSource() == dateofPurchase) || (evt.getSource() == enter))
                 { // Opens if statement.
                   // Retrieves the text from the dateofPurchase text field
                   // and assigns it to the variable dateofPurchaseText of
                   // type String.
                   String dateofPurchaseText = dateofPurchase.getText();
                   lbldateofPurchase.setText("The date of this purchase is:    " + dateofPurchaseText);
                   // After printing text to JLabel, hide the text field.
                   dateofPurchase.setVisible(false);
       } // Ends if statement.
       if((evt.getSource() == pricePerGallon) || (evt.getSource() == enter))
                        { // Opens if statement.
                          // Retrieves the text from the pricePerGallon text field
                          // and assigns it to the variable pricePerGallonText of
                          // type String.
                          String pricePerGallonText = pricePerGallon.getText();
                          lblpricePerGallon.setText("The price per gallon of gas for this purchase is:    " + pricePerGallonText);
                          // After printing text to JLabel, hide the text field.
                          pricePerGallon.setVisible(false);
       } // Ends if statement.
       if((evt.getSource() == gasBrand) || (evt.getSource() == enter))
                   { // Opens if statement.
                     // Retrieves the text from the gasBrand text field
                     // and assigns it to the variable gasBrandText of
                     // type String.
                     String gasBrandText = gasBrand.getText();
                     lblgasBrand.setText("The Brand of gas for this purchase is:    " + gasBrandText);
                     // After printing text to JLabel, hide the text field.
                     gasBrand.setVisible(false);
       } // Ends if statement.
       // This provides control statements for the Edit button. If the
       // Edit button is clicked, then the text fields are visible again.
       if(evt.getSource() == edit)
       { // Opens if statement.
         // If the edit button is pressed, the following are set to
         // visible.
            currentMileage.setVisible(true);
            numofGallonsBought.setVisible(true);
            dateofPurchase.setVisible(true);
            pricePerGallon.setVisible(true);
            gasBrand.setVisible(true);
     }// Closes if statement.
} // Closes actionPerformed method.
     private class CheckBoxHandler implements ItemListener
     { // Opens inner class
          public void itemStateChanged (ItemEvent e)
          {// Opens the itemStateChanged method.
               JCheckBox source = (JCheckBox) e.getSource();
                    if(e.getStateChange() == ItemEvent.SELECTED)
                         source.setForeground(Color.blue);
                    else
                         source.setForeground(Color.black);
                    }// Closes the itemStateChanged method
               }// Closes the CheckBoxHandler class.
} //Ends the public class collectTextInput classThe error I keep receiving is as follows:
C:\jdk131\CollectTextInput.java:128: missing method body, or declare abstract
     public void buildImagePanel();
^
C:\jdk131\CollectTextInput.java:142: missing method body, or declare abstract
     public void buildDatumPanel();
^
2 errors
I have looked this error up in three different places but the solutions do not apply to what I am trying to accomplish.
Any help would be greatly appreciated!! Thanks!
Susan

C:\jdk131\CollectTextInput.java:128: missing methodbody, or declare ?abstract
public void buildImagePanel();^
C:\jdk131\CollectTextInput.java:142: missing methodbody, or declare abstract
public void buildDatumPanel();Just remove the semicolons.
Geesh! If I had a hammer I would be hitting myself over the head with it right now!!! What an obviously DUMB newbie mistake!!!
Thanks so much for not making me feel stupid! :-)
Susan

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Hello,
I am a newbie to GUIs in java. I am writing an application that has 4 buttons.
You can run the codes below to see how it looks.
I need it to connect to an oracle server when the "Connect to Server" button is clicked
If the connection is successful,It should set the text on lblStatus to "Connected", and the
"Get sales amount" and "Close connection" buttons should be enabled, while the
"Connect to server button be disable"
Otherwise a dialog box should pop up, displaying "Cannot connect to server").
If the "Get Sales amount" button is clicked, it should display a dialog box that will
accept user input for a store name and it should display the corresponding sales
value from the SALES table. If the user input is "all". It should display sale amount for all
stores in the SALES table.
If the "Close connection" button is clicked, it should close the connection to server
and display appropraite information in the lblStatus bar.
My codes
==================
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.event.*;
public class ConnectorDemo{
public static void main (String [] args) {
//Create window,its size, panel and add the message to be displayed at the bottom
JFrame frame = new JFrame("Java Coursework");
frame.setSize(350,220);
JPanel p = new JPanel(new BorderLayout());
p.add(new JLabel("Not connected"),BorderLayout.SOUTH);
// Create components,their equal sizes,locations and enable or disable them
JButton buttonOne;
buttonOne = new JButton("Connect to server");
buttonOne.setSize(220,30);
buttonOne.setEnabled(true);
buttonOne.setLocation(80,20);
JButton buttonTwo;
buttonTwo = new JButton("Get Sales Amount");
buttonTwo.setSize(220,30);
buttonTwo.setEnabled(false);
buttonTwo.setLocation(80,60);
JButton buttonThree;
buttonThree = new JButton("Close connection to server");
buttonThree.setSize(220,30);
buttonThree.setEnabled(false);
buttonThree.setLocation(80,100);
JButton buttonFour;
buttonFour = new JButton("Exit");
buttonFour.setSize(220,30);
buttonFour.setEnabled(true);
buttonFour.setLocation(80,140);
buttonFour.addActionListener (new ButtonFourListener());
// Add components to the window
frame.getContentPane().add(buttonOne);
frame.getContentPane().add(buttonTwo);
frame.getContentPane().add(buttonThree);
frame.getContentPane().add(buttonFour);
frame.getContentPane().add(p);
// Display window
frame.setVisible(true);
static class ButtonFourListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
JButton buttonFour = (JButton) e.getSource();
System.exit(0);
}//End listener
Database
================
CREATE TABLE SALES(
shop_name VARCHAR2(30),
sale_amount INTEGER);
INSERT INTO SALES VALUES('waitrose', 1500);
INSERT INTO SALES VALUES('argos', 1500);
INSERT INTO SALES VALUES('asda', 1500);
INSERT INTO SALES VALUES('tesco', 1500);

You're going to need to create ActionListeners for the buttons, just like the ActionListener for button 4, except you'll want to do different things when the buttons are pressed. Here's a tutorial on ActionListeners and handling events: http://java.sun.com/docs/books/tutorial/uiswing/learn/example2.html#handlingEvents

Panic! Possible to change Fontcolor in List in AWT?

I really need to know if it is possible to change the font color in AWT for different list entries in th awt.List object.
I managed to change the fonts with no problem, but the font color...
I�m using my list as an own object which extends the panel. Is this the right way to do it or?
If anyone has any hints or a piece of sample code (if it is possible) please let me know.
//Peter
//To call the Lists class from outside
private void setupTheList()
String[] str = {"2","4","","","","","","","","","","","","","","","","",""}; //Items to be added to the List.
int[] sel = {1,4,7,8,9,13}; //Which are to be selected in the List
li = new Lists(str,5,sel);
class Lists extends Panel{
List list;
public void paint(Graphics g)
Graphics g2;
g2 = list.getGraphics();
g2.setColor(Color.red);
public Lists(String[] listItems, int listLength, int[] listItemSelected){
list = new List(listLength,true);
for(int i = 0; i < listItems.length; i++){
list.add(new String(listItems));
for(int j = 0; j < listItemSelected.length; j++){
list.select(listItemSelected[j]);
GridBagLayout gbl = new GridBagLayout();
setLayout(gbl);
add(list);

Of course create your own list you need a scrollbar, canvas or panel, and implements Mouselistener, and ItemListener after that you draw what Color, image or text you want.

Handling events in combo box

Hello,
I'm very much confused about the handling events of JComboBox with ActionListener and ItemListener. Both are seemed similar to me. If anyone can explain me the differences, it would be helpful for me. Thanks everybody.

ActionEvents are fired each time any item is selected, ItemEvents are only fired, if the selection changes.

Keep getting only 1 error

Hello everyone,
I am new to Java. I have a program that should change the background color when a button is clicked.
I keep getting the same error no matter what I do.
The error is "cannot resolve symbol
symbol: variable e
String arg = e.getActionCommand();
The error is on the second string statement.
Here is the code:
import java.awt.*;
import java.awt.event.*;
public class Buttons extends Frame implements ActionListener,ItemListener
     public Buttons()
     //set the layout
     setLayout(new BorderLayout(20,5));
           //Add buttons and Choice
           Button north = new Button("Red");
           Button south = new Button("Yellow");
           Button east = new Button("Cyan");
           Button west = new Button("Magenta");
           Choice colors = new Choice();
     //Add buttons and Choice to the frame
     add(north, BorderLayout.NORTH);
     add(south, BorderLayout.SOUTH);
     add(east, BorderLayout.EAST);
     add(west, BorderLayout.WEST);
     add(colors, BorderLayout.CENTER);
     //populating the Choice component
     colors.add("Red");
     colors.add("Yellow");
     colors.add("Cyan");
     colors.add("Magenta");
     colors.add("White");
     //Add ActionListener to buttons and ItemListener to Choice component
     north.addActionListener(this);
     south.addActionListener(this);
     east.addActionListener(this);
     west.addActionListener(this);
     colors.addItemListener(this);
     //override the windowClosing event
     addWindowListener(
              new WindowAdapter()
              public void windowClosing(WindowEvent e)
              System.exit(0);
     }// End of Constructor method
        public static void main(String[] args)
      // set frame properties
     Buttons f = new Buttons();
           f.setTitle("Button Application");
           f.setBounds(200,200,300,300);
     f.setVisible(true);
     f.setBackground(Color.RED);
                     public void actionPerformed(ActionEvent e)
             String arg = e.getActionCommand();
             if (arg == "Red")
             setBackground(Color.RED);
             if (arg == "Yellow")
             setBackground(Color.YELLOW);
             if (arg == "Cyan")
             setBackground(Color.CYAN);
             if (arg == "Magenta")
             setBackground(Color.MAGENTA);
             if (arg == "White")
             setBackground(Color.WHITE);
     public void itemStateChanged(ItemEvent ie)
          String arg = e.getActionCommand();
          if (arg == "Red")
          setBackground(Color.RED);
          if (arg == "Yellow")
          setBackground(Color.YELLOW);
          if (arg == "Cyan")
          setBackground(Color.CYAN);
          if (arg == "Magenta")
          setBackground(Color.MAGENTA);
          if (arg == "White")
          setBackground(Color.WHITE);
}

Hello everyone,
I have updated my code. It compiles now. The buttons work properly, but when a color from the Choice arrow is selected it changes the background color to white and it never changes unless I click a button.
What am I doing wrong?
import java.awt.*;
import java.awt.event.*;
public class Buttons extends Frame implements ActionListener,ItemListener
     public Buttons()
          //set the layout
          setLayout(new BorderLayout(20,5));
           //Add buttons and Choice
           Button north = new Button("Red");
           Button south = new Button("Yellow");
           Button east = new Button("Cyan");
           Button west = new Button("Magenta");
           Choice colors = new Choice();
     //Add buttons and Choice to the frame
     add(north, BorderLayout.NORTH);
     add(south, BorderLayout.SOUTH);
     add(east, BorderLayout.EAST);
     add(west, BorderLayout.WEST);
     add(colors, BorderLayout.CENTER);
     //populating the Choice component
     colors.add("Red");
     colors.add("Yellow");
     colors.add("Cyan");
     colors.add("Magenta");
     colors.add("White");
     //Add ActionListener to buttons and ItemListener to Choice component
     north.addActionListener(this);
     south.addActionListener(this);
     east.addActionListener(this);
     west.addActionListener(this);
     colors.addItemListener(this);
     //override the windowClosing event
     addWindowListener(
     new WindowAdapter()
          public void windowClosing(WindowEvent e)
               System.exit(0);
     }// End of Constructor method
        public static void main(String[] args)
          // set frame properties
         Buttons f = new Buttons();
               f.setTitle("Button Application");
               f.setBounds(200,200,300,300);
         f.setVisible(true);
         f.setBackground(Color.RED);
                     public void actionPerformed(ActionEvent e)
            String arg = e.getActionCommand();
            if (arg == "Red")
            setBackground(Color.RED);
            if (arg == "Yellow")
           setBackground(Color.YELLOW);
           if (arg == "Cyan")
           setBackground(Color.CYAN);
           if (arg == "Magenta")
           setBackground(Color.MAGENTA);
           if (arg == "White")
           setBackground(Color.WHITE);
     public void itemStateChanged(ItemEvent ie)
          if (ie.getStateChange() == ItemEvent.SELECTED)
          setBackground(Color.RED);
          if (ie.getStateChange() == ItemEvent.SELECTED)
          setBackground(Color.YELLOW);
          if (ie.getStateChange() == ItemEvent.SELECTED)
          setBackground(Color.CYAN);
          if (ie.getStateChange() == ItemEvent.SELECTED)
          setBackground(Color.MAGENTA);
          if (ie.getStateChange() == ItemEvent.SELECTED)
          setBackground(Color.WHITE);
}Thanks for your assistance

Forms don't submit when mixed w/ Javascript

Greetings,
I have a problem with a JSF application
I have a JSF form with a number of text fields (h:inputText) and text areas. None are set to be required and all use the default validators, converters, etc. Each text element is bound to a String property of a backing bean. All works fine under 'normal' conditions. I submit the form, the values are all set on the backing bean, all is well.
Next to one (or more) of the textfields, however, there is a "Select..." button (h:commandButton) with a javascript call on the 'onmousedown' event that launches a new window (this is a slightly modified version of the example found at http://forum.exadel.com/viewtopic.php?t=559 by Sergey Smirnov). The selected value in the popup window is used to set the value on the original form text field. Then the original form can be submitted.
When I use one of these buttons to launch a new window (pop-up) with a JSF-based select list in it, I get unusual behavior. The syptoms I see are:
1. If the popup list itself submits and refreshes (such as in the case of an indexed list, and the user selects a new index) the value is set properly on the 'opener' form, but when I submit the 'opener' form, the value reverts back to its previous (before the pop-up was launched) value.
2. Especially with more than 1 pop-up on a form, I often see the case where I submit the form, and it simply refreshes itself, and all values are cleared from the form elements. My ActionListeners and other action events are never invoked. No messages are sent back to the page via the faces context. I get no notification of what went wrong.
3. The behavior I get is hit or miss, sometimes it works well, other times it never works.
4. Strangely, it seems that if I click more slowly, things tend to work better more often. Rapid clicking seems to make the failure much more likely.
The Button looks like this:
<h:inputText id="itemValue" value="#{item.value}"/>
<h:inputHidden id="itemId" value="#{item.id}"/>
<h:inputHidden id="itemTypeId" value="#{item.typeId}"/>
<h:commandButton id="find" action="showList" value="Select..."
onmousedown="showList(this,'itemValue', 'itemId', 'itemTypeId')"
onclick="return false"/>
The javascript showList() method registers the html components itemValue, itemId, and itemTypeId for callbacks, and launches a window using a pre-defined href value. Inside this window is a JSF page that lists all of the available items as h:commandLink objects. When one of the links is selected, the pop-up window calls a javascript function on the 'opener' window to set the itemValue, itemId, and itemTypeId values according to the selected item.
function showList(action, nameFieldComponent, idFieldComponent, itemTypeIdComponent) {
//url to the chooser.jsp file opened in the new window
var href='<h:outputText value="#{bundle.chooser_javascript_href}" />';
var features='<h:outputText value="#{bundle.chooser_javascript_window_properties}" />';
<...snipped out details for brevity - resolves the form and component ids for callbacks >
//open the new window
winId=window.open(href,'chooserWindow',features);
A javascript function in the chooser.jsp calls back and update() method, which sets the values on the name, id, and typeId form elements. All this works fine.
It's AFTER all this, when I submit the form on the original page, that I get the errors.
I suspect that somehow with more than 1 window open, I've managed to confuse the Faces navigation and view management - does anybody have any insights to help me solve the problem?
Also, how can I better debug what is happening on the server when my action listener is never getting invoked?

This is just a shot in the dark, but have you tried switching to client-side state saving?
When you use server-side state saving, the JSF RI only keeps the state for one view around. If your pop-ups are created by JSF views, popping up one of them detroys the state for the main view on the server, which could cause the effects you describe. Switching to client-side state saving should solve this, because then the view state is held as hidden fields in each form instead, and hence, can't be destroyed.

How to create a single action listener for a group of buttons

hi there.. i am new at java and i have a problem with my applet..
i am doing a virtual ticket programme..
i have a tab that says books seats.. in the tab, i am suppose to create 50 buttons.
i have done that already by using for (int i=1; i<=10;i++) 5 times for 50 buttons.
but i do not know how to set an actionlistener in the for loop for each of these buttons..
For example, if the user were to chose seat "no3" , a text area(already created) below will show something like "no3" and so on..
how do i bind these buttons into one single action listener so i do not have to create 50 actionlisteners and buttons individually..
appreciate the help..

You're killing me.
class MyFrame extends JFrame implements ActionListener
     JTextArea myTextArea = new JTextArea();
     JButton myButton = new JButton("My Button");
     JButton otherButton = new JButton("Other Button");
     MyFrame()
          super();
          myButton.addActionListener(this);
          otherButton.addActionListener(this);
          setLayout(new FlowLayout());
          add(myButton);
          add(otherButton);
          add(myTextArea);
     public void actionPerformed(ActionEvent e)
          Object source = e.getSource();
          if(source == myButton)
               myTextArea.append("My Button Pressed\n");
          else if(source == otherButton)
               myTextArea.append("Other Button Pressed\n");
}

ActionListeners and ItemListener

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