Develop Reference

Click a button to open a new JFrame / GUI,

I seem to not be able to find a way to get my code to work.
I am making a program and until now everything was working, i have some buttons and they do what they should.
But now i added a button that when a user click it, it should close the current GUI and open a new one.
I also want to point out that i created a new class for this new GUI.
The other GUI class that i want to call is the GuiCrafting, in that class the GUI is also all coded, and works if i call it on the Main.
My question is what do i type here (I tried a lot of things like dispose() etc but i just get error messages) :
public void actionPerformed(ActionEvent event) {
if( str.equals("Crafting")){
//insert code to call the GuiCrafting class and open his GUI
}
Thanks in advance and if you need something more please let me know.

Multiple JFrames are frowned upon as you can read about here and here
Perhaps what you want to use is a CardLayout which manages two or more components (usually JPanel instances) that share the same display space.
After clicking the button "Goto Card 2"
TestApp.java:
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.event.ActionEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class TestApp {
final static String CARD1 = "Card1";
final static String CARD2 = "Card2";
public TestApp() {
initComponents();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(TestApp::new);
}
private void initComponents() {
JFrame frame = new JFrame("TestApp");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// create the panel that contains the "cards".
JPanel cards = new JPanel(new CardLayout());
// card 1 components
JButton buttonGotoCard2 = new JButton("Goto Card 2");
buttonGotoCard2.addActionListener((ActionEvent e) -> {
CardLayout cl = (CardLayout) (cards.getLayout());
cl.show(cards, CARD2);
});
// create card 1
JPanel card1 = new JPanel();
card1.add(new JLabel("Card 1"));
card1.add(buttonGotoCard2);
// card 2 components
JButton buttonGotoCard1 = new JButton("Goto Card 1");
buttonGotoCard1.addActionListener((ActionEvent e) -> {
CardLayout cl = (CardLayout) (cards.getLayout());
cl.show(cards, CARD1);
});
// create card 2
JPanel card2 = new JPanel();
card2.add(new JLabel("Card 2"));
card2.add(buttonGotoCard1);
// add cards to cards panel
cards.add(card1, CARD1);
cards.add(card2, CARD2);
frame.getContentPane().add(cards, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
}
There is also a JDialog which could be what you want.
HOWEVER
You can easily do something like that (Open a JFrame from another If you must):
TestApp.java:
import java.awt.event.ActionEvent;
import java.awt.event.WindowAdapter;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.EmptyBorder;
public class TestApp {
public TestApp() {
initComponents();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(TestApp::new);
}
private void initComponents() {
JFrame mainFrame = new JFrame();
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
panel.setBorder(new EmptyBorder(10, 10, 10, 10));
JLabel label = new JLabel("JFrame 1");
JButton button = new JButton("Open JFrame 2");
button.addActionListener((ActionEvent e) -> {
this.showNewJFrame(new WindowAdapter() {
#Override
public void windowClosing(java.awt.event.WindowEvent e) {
// here we listen for the second JFrame being closed so we can bring back the main JFrame
mainFrame.setVisible(true);
}
});
// hide the main JFrame
mainFrame.setVisible(false);
});
panel.add(label);
panel.add(button);
mainFrame.add(panel);
mainFrame.pack();
mainFrame.setVisible(true);
}
private void showNewJFrame(WindowAdapter windowAdapter) {
JFrame frame2 = new JFrame();
frame2.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); // we dont wnat to exit when this JFrame is closed
JPanel panel2 = new JPanel();
panel2.setLayout(new BoxLayout(panel2, BoxLayout.Y_AXIS));
panel2.setBorder(new EmptyBorder(10, 10, 10, 10));
JLabel label2 = new JLabel("JFrame 2");
panel2.add(label2);
frame2.add(panel2);
frame2.addWindowListener(windowAdapter);
frame2.pack();
frame2.setVisible(true);
}
}
This produces:
and when the "Open JFrame 2" is clicked:
and when JFrame 2 is closed it brings back the main JFrame via the WindowAdapter#windowClosing.

Using button in a panel class to call ActionListener in the frame class

I started codig Java last weekend and I've read most of the basic stuff. I'm trying to separate my frame from main method, and panels from the frame so they are all in separate class files. I have trouble calling ActionLister in "Frame1" class with a button (buttonBack) in the "TheGame" class. The button should trigger the Listener which in turn should remove theGame panel and add mainMenu panel to frame1. I know that CardLayout is better suited for swapping panels but i want to learn the limits and workarounds before i go do it the "easy" way, i feel that you learn much more that way.
Here is some of my code:
Main:
public class Main {
public static void main(String[] args){
Frame1 frame1 = new Frame1();
frame1.frame1();
}
}
Frame1:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
class Frame1 {
private JFrame frame1 = new JFrame("Name");
public void frame1() {
TheGame theGame = new TheGame();
MainMenu mainMenu = new MainMenu();
// Frame options
frame1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame1.setLocationRelativeTo(null);
// Creating a top menu
JMenuBar menubar = new JMenuBar();
frame1.setJMenuBar(menubar);
JMenu file = new JMenu("File");
menubar.add(file);
JMenu help = new JMenu("Help");
menubar.add(help);
JMenuItem exit = new JMenuItem("Exit");
file.add(exit);
JMenuItem about = new JMenuItem("About");
help.add(about);
// Creating action for the menuitem "exit".
class exitaction implements ActionListener{
public void actionPerformed (ActionEvent e){
System.exit(0);
}
}
exit.addActionListener(new exitaction());
// Creating listener for the menuitem "about".
class aboutaction implements ActionListener{
public void actionPerformed (ActionEvent e){
JDialog dialogabout = new JDialog();
JOptionPane.showMessageDialog(dialogabout, "Made by: ");
}
}
about.addActionListener(new aboutaction());
// Add the panels, pack and setVisible
theGame.theGame();
mainMenu.mainMenu();
frame1.add(theGame.getGUI());
// This is the ActionListener i have trouble connecting with the buttonBack in the "theGame" class
class Action implements ActionListener{
public void actionPerformed (ActionEvent e){
frame1.remove(theGame.getGUI());
frame1.add(MainMenu.getGUI());
}
}
frame1.pack();
frame1.setVisible(true);
}
public JFrame getGUI() {
return frame1;
}
}
MainMenu:
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JPanel;
class MainMenu {
private JPanel mainMenu = new JPanel (new GridBagLayout());
public void mainMenu() {
// Using the GridBagLayout therefore creating the constraints "grid"
GridBagConstraints grid = new GridBagConstraints();
// Adjusting grid insets
grid.insets = new Insets(10, 10, 10, 10);
// Creating Label
JLabel introduction = new JLabel("Name");
grid.gridx = 1;
grid.gridy = 3;
mainMenu.add(introduction, grid);
// Creating buttons Start Game, Highscore and Exit Game
JButton buttonNewGame = new JButton("New Game");
buttonNewGame.setPreferredSize(new Dimension(200, 50));
grid.gridx = 1;
grid.gridy = 5;
mainMenu.add(buttonNewGame, grid);
JButton buttonHighscore = new JButton("Highscore");
buttonHighscore.setPreferredSize(new Dimension(200, 50));
grid.gridx = 1;
grid.gridy = 6;
mainMenu.add(buttonHighscore, grid);
JButton buttonExit = new JButton("Exit Game");
buttonExit.setPreferredSize(new Dimension(200, 50));
grid.gridx = 1;
grid.gridy = 7;
mainMenu.add(buttonExit, grid);
}
public JComponent getGUI() {
return mainMenu;
}
}
TheGame:
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JPanel;
class TheGame {
private JPanel theGame = new JPanel (new GridBagLayout());
public void theGame() {
// Using the GridBagLayout therefore creating the constraints "grid"
GridBagConstraints grid = new GridBagConstraints();
// Adjusting grid insets
grid.insets = new Insets(10, 10, 10, 10);
// Creating a label
JLabel label1 = new JLabel("Press the BACK button to go back to Main Menu");
label1.setVisible(true);
grid.gridx = 1;
grid.gridy = 0;
theGame.add(label1,grid);
// Creating BACK button
JButton buttonBack = new JButton("BACK");
buttonBack.setVisible(true);
grid.gridx = 1;
grid.gridy = 1;
buttonBack.addActionListener(new --); // This is the button i want to connect with the ActionListener on Frame1 class
theGame.add(buttonBack, grid);
}
public JComponent getGUI() {
return theGame;
}
}
I've tried moving the ActionListener outside of methods, inside the Main, declaring it static, but haven't been able to call it anyways. I've also looked at other posts like this: Add an actionListener to a JButton from another class but have not been able to implement it in to my code.
Any help is appreciated.

The best answer -- use MVC (model-view-controller) structure (and CardLayout) for the swapping of your views. If you don't want to do that, then your listener should have a reference to the container that does the swapping, and so that the listener can notify this container that a swap should occur. The container will then call its own code to do the swapping. To do this you need to pass references around including a reference to the main GUI to wherever it is needed. This can get messy, which is why MVC, which is more work, is usually better -- fewer connections/complexity in the long term.
Side note -- don't pass a JDialog into a JOptionPane as a JOptionPane is a specialized JDialog, and you shouldn't have a top level window displaying a top level window. Instead pass in a JPanel.
For example:
import java.awt.CardLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import javax.swing.*;
public class PassRef {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
createAndShowGui();
});
}
private static void createAndShowGui() {
MyMain mainPanel = new MyMain();
JFrame frame = new JFrame("Pass Reference");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
}
class MyMain extends JPanel {
private static final int PREF_W = 600;
private static final int PREF_H = 450;
private CardLayout cardLayout = new CardLayout();
private MenuView menuView = new MenuView(this);
private ActionView1 actionView1 = new ActionView1(this);
public MyMain() {
setLayout(cardLayout);
add(menuView, MenuView.NAME);
add(actionView1, ActionView1.NAME);
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
} else {
return new Dimension(PREF_W, PREF_H);
}
}
public void showCard(String key) {
cardLayout.show(this, key);
// or swap by hand if you don't want to use CardLayout
// but remember to revalidate and repaint whenever doing it by hand
}
}
class MenuView extends JPanel {
public static final String NAME = "Menu View";
public MenuView(MyMain myMain) {
setName(NAME);
setBorder(BorderFactory.createTitledBorder("Menu"));
add(new JButton(new GoToAction("Action 1", ActionView1.NAME, myMain)));
}
}
class ActionView1 extends JPanel {
public static final String NAME = "Action View 1";
public ActionView1(MyMain myMain) {
setName(NAME);
setBorder(BorderFactory.createTitledBorder(NAME));
add(new JButton(new GoToAction("Main Menu", MenuView.NAME, myMain)));
}
}
class GoToAction extends AbstractAction {
private String key;
private MyMain myMain;
public GoToAction(String name, String key, MyMain myMain) {
super(name);
this.key = key;
this.myMain = myMain;
}
#Override
public void actionPerformed(ActionEvent e) {
myMain.showCard(key);
}
}

GUI application that changes background with button

I am trying to create a Java GUI application that contains a label and button. When the button is clicked the background color of the first panel is changed. I've got the label and button but getting errors whenever I click the button. Also, I wanted the first panel to originally have a yellow background then switch to whatever color. Here's my code:
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.FlowLayout;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JLabel;
public class ChangeDemo extends JFrame implements ActionListener
{
public static final int WIDTH = 300;
public static final int HEIGHT= 200;
private JPanel biggerPanel;
public static void main(String[] args)
{
ChangeDemo gui = new ChangeDemo();
gui.setVisible(true);
}
public ChangeDemo()
{
super ("ChangeBackgroundDemo");
setSize(WIDTH,HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new GridLayout(2,3));
JPanel biggerPanel = new JPanel();
biggerPanel.setLayout(new BorderLayout());
biggerPanel.setBackground(Color.YELLOW);
JLabel namePanel = new JLabel("Click the button to change the background color");
biggerPanel.add(namePanel, BorderLayout.NORTH);
add(namePanel);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout());
buttonPanel.setBackground(Color.LIGHT_GRAY);
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(this);
buttonPanel.add(changeButton);
add(buttonPanel);
}
public void actionPerformed(ActionEvent e)
{
String buttonString = e.getActionCommand();
if(buttonString.equals("Change Color"))
biggerPanel.setBackground(Color.RED);
else
System.out.println("Unexpected Error!");
}
}

I made a few changes to your code.
First, you must start a Swing application with a call to SwingUtilities.invokeLater.
public static void main(String[] args) {
SwingUtilities.invokeLater(new ChangeDemo());
}
Second, you use Swing components. You only extend a Swing component when you want to override a method of the Swing component.
Third, I made a action listener specifically for your JButton. That way, you don't have to check for a particular JButton string. You can create as many action listeners as you need for your GUI.
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
isYellow = !isYellow;
if (isYellow) buttonPanel.setBackground(Color.YELLOW);
else buttonPanel.setBackground(Color.RED);
}
});
Finally, I changed the background color of the JButton panel.
Here's the entire ChangeDemo class.
package com.ggl.testing;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class ChangeDemo implements Runnable {
private boolean isYellow;
private JFrame frame;
public static void main(String[] args) {
SwingUtilities.invokeLater(new ChangeDemo());
}
#Override
public void run() {
frame = new JFrame("Change Background Demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel mainPanel = new JPanel();
mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.PAGE_AXIS));
JPanel namePanel = new JPanel();
JLabel nameLabel = new JLabel(
"Click the button to change the background color");
nameLabel.setAlignmentX(JLabel.CENTER_ALIGNMENT);
namePanel.add(nameLabel);
mainPanel.add(namePanel);
final JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout());
buttonPanel.setBackground(Color.YELLOW);
isYellow = true;
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
isYellow = !isYellow;
if (isYellow) buttonPanel.setBackground(Color.YELLOW);
else buttonPanel.setBackground(Color.RED);
}
});
buttonPanel.add(changeButton);
mainPanel.add(buttonPanel);
frame.add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
}

Here is working demo based on amendments to your code, haven't had time to tidy it up but hopefully you'll get the gist of it. Problem was you hand't added Panels to the borders (north, south etc.) in order to color them. Hopefully this helps.
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.FlowLayout;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JLabel;
public class ChangeDemo extends JFrame implements ActionListener
{
public static final int WIDTH = 300;
public static final int HEIGHT= 200;
private JPanel biggerPanel = new JPanel();
private JPanel namePanel = new JPanel();
public static void main(String[] args)
{
ChangeDemo gui = new ChangeDemo();
gui.setVisible(true);
}
public ChangeDemo()
{
super ("ChangeBackgroundDemo");
setSize(WIDTH,HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new GridLayout(2,3));
//JPanel biggerPanel = new JPanel();
this.biggerPanel.setLayout(new BorderLayout());
this.biggerPanel.setBackground(Color.YELLOW);
JLabel nameLabel = new JLabel("Click the button to change the background color");
namePanel.add(nameLabel);
namePanel.setBackground(Color.YELLOW);
//this.biggerPanel.add(namePanel, BorderLayout.NORTH);
add(namePanel);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout());
buttonPanel.setBackground(Color.LIGHT_GRAY);
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(this);
changeButton.setActionCommand("Change Color");
buttonPanel.add(changeButton);
add(buttonPanel);
}
public void actionPerformed(ActionEvent e)
{
String buttonString = e.getActionCommand();
if(buttonString.equals("Change Color"))
this.namePanel.setBackground(Color.RED);
else
System.out.println("Unexpected Error!");
}
}

(Java) Why is this tabbed pane not working correctly?

Note: I've searched all over the web (this site and others) and cannot answer this myself.
Ok guys. I am a new Java programmer, and we just got done covering tabbed panes. This is the state in which I turned in my assignment: it doesn't work, and I can't figure out why. I've changed so much crap around, I can't keep it straight in my head anymore, but I know it's probably something incredibly simple.
I apologize for the length of the code, but I'm trying to give you the entirety of my code so you can tell me where I jacked it up.
Thanks in advance. -- Also, I'm aware there are other Warnings (i.e. unused imports), but I'm not worried about those. And, this will not affect my grade (as I said, already submitted), but I want to know wtf I did wrong!
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.text.DecimalFormat;
import java.awt.Color;
import javax.swing.JOptionPane;
import javax.swing.JTabbedPane;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JPanel;
import javax.swing.JComponent;
public class TabbedPane1 extends JPanel
{
public TabbedPane1()
{
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("DayGui", new DayGui());
tabbedPane.addTab("OfficeCalc", new OfficeAreaCalculator());
add(tabbedPane);
}
public static void main(String[] args)
{
JFrame myFrame = new JFrame("Tabbed Programs");
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.add(new TabbedPane1(), BorderLayout.CENTER);
myFrame.pack();
myFrame.setVisible(true);
}
class DayGui extends JPanel
{
private JPanel mainFrame;
private JButton cmdGood;
private JButton cmdBad;
public DayGui()
{
mainFrame = new JPanel();
cmdGood = new JButton("Good");
cmdBad = new JButton("Bad");
Container myContainer = mainFrame;
myContainer.setLayout(new FlowLayout());
myContainer.add(cmdGood);
myContainer.add(cmdBad);
cmdGood.setMnemonic('G');
cmdBad.setMnemonic('B');
mainFrame.setSize(300, 100);
myContainer.setBackground(Color.blue);
cmdGood.setBackground(Color.cyan);
cmdBad.setBackground(Color.cyan);
/*mainFrame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});*/
ButtonsHandler bhandler = new ButtonsHandler();
cmdGood.addActionListener(bhandler);
cmdBad.addActionListener(bhandler);
//mainFrame.setVisible(true);
}
class ButtonsHandler implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
if(e.getSource() == cmdGood)
JOptionPane.showMessageDialog(null, "Today is a good day!",
"Event Handler Message",
JOptionPane.INFORMATION_MESSAGE);
if(e.getSource() == cmdBad)
JOptionPane.showMessageDialog(null, "Today is a bad day!",
"Event Handler Message",
JOptionPane.INFORMATION_MESSAGE);
}
}
}
class OfficeAreaCalculator extends JPanel
{
private JPanel mainFrame;
private JButton calculateButton;
private JButton exitButton;
private JTextField lengthField;
private JTextField widthField;
private JTextField areaField;
private JLabel lengthLabel;
private JLabel widthLabel;
private JLabel areaLabel;
public OfficeAreaCalculator()
{
mainFrame = new JPanel();
exitButton = new JButton("Exit");
calculateButton = new JButton("Calculate");
lengthField = new JTextField(5);
widthField = new JTextField(5);
lengthLabel = new JLabel("Enter the length of the office:");
widthLabel = new JLabel("Enter the width of the office:");
areaLabel = new JLabel("Office area:");
areaField = new JTextField(5);
areaField.setEditable(false);
Container c = mainFrame;
c.setLayout(new FlowLayout());
c.setBackground(Color.green);
c.add(lengthLabel);
c.add(lengthField);
c.add(widthLabel);
c.add(widthField);
c.add(areaLabel);
c.add(areaField);
c.add(calculateButton);
c.add(exitButton);
calculateButton.setMnemonic('C');
exitButton.setMnemonic('x');
mainFrame.setSize(260, 150);
/*mainFrame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});*/
CalculateButtonHandler chandler = new CalculateButtonHandler();
calculateButton.addActionListener(chandler);
ExitButtonHandler ehandler = new ExitButtonHandler();
exitButton.addActionListener(ehandler);
FocusHandler fhandler = new FocusHandler();
lengthField.addFocusListener(fhandler);
widthField.addFocusListener(fhandler);
areaField.addFocusListener(fhandler);
//mainFrame.setVisible(true);
}
class CalculateButtonHandler implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
DecimalFormat num = new DecimalFormat(",###.##");
double width, length, area;
String instring;
instring = lengthField.getText();
if(instring.equals(""))
{
instring = ("0");
lengthField.setText("0");
}
length = Double.parseDouble(instring);
instring = widthField.getText();
if(instring.equals(""))
{
instring = ("0");
widthField.setText("0");
}
width = Double.parseDouble(instring);
area = length * width;
areaField.setText(num.format(area));
}
}
class ExitButtonHandler implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
System.exit(0);
}
}
class FocusHandler implements FocusListener
{
public void focusGained(FocusEvent e)
{
if(e.getSource() == lengthField || e.getSource() == widthField)
{
areaField.setText("");
}
else if(e.getSource() == areaField)
{
calculateButton.requestFocus();
}
}
public void focusLost(FocusEvent e)
{
if(e.getSource() == widthField)
{
calculateButton.requestFocus();
}
}
}
}
}

You added your JTabbedPane on JPanel.
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("DayGui", new DayGui());
tabbedPane.addTab("OfficeCalc", new OfficeAreaCalculator());
add(tabbedPane);
Since JPanel has a FlowLayout as a default, you have this issue. Set layout of your JPanelto BorderLayout and problem will be solved.
setLayout(new BorderLayout()); //Here
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("DayGui", new DayGui());
tabbedPane.addTab("OfficeCalc", new OfficeAreaCalculator());
add(tabbedPane);
EDIT:
Also, avoid extending your classes with swing components if you don't want to override methods or define new ones. Prefer composition instead of that. I had that same bad habbit.
For example, instead of extending tour TabbedPane1 class with JPanel, it would be better to just create a method which returns customized JTabbedPane. Something like this:
public JTabbedPane getTabbedPane() {
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("DayGui", new DayGui());
tabbedPane.addTab("OfficeCalc", new OfficeAreaCalculator());
return tabbedPane;
}
To call it:
myFrame.add(new TabbedPane1().getTabbedPane(), BorderLayout.CENTER);
This way your class will be "opened" for inheritance.

How to remove the blue line from a Panel after creating a TitleBorder using BorderFactory?

I created a JPanel and i have added a TitleBorder with BorderFactory but it's showing a blue line around the panel.
I would like to remove this line.
Any suggestions?
Thank you

never tried to extract this value from TitleBorders API, methods are protected, or by using UIManager
have to use LineBorder inside TitleBorder
simpliest syntax could be xxx.setBorder(new TitledBorder(new LineBorder(Color.ORANGE, 1), "label")); or get the Color from (for example) myPanel.getBackground() instread of Color.ORANGE
another options are (is possible)
move desciption (top, bottom.....)
change Font
change Foreground (Color for description)
more options and description in Oracle tutorial How to Use Borders (CompounBorders)
for example
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.LineBorder;
import javax.swing.border.TitledBorder;
public class AddComponentsAtRuntime {
private JFrame f;
private JPanel panel;
private JCheckBox checkValidate, checkReValidate, checkRepaint, checkPack;
public AddComponentsAtRuntime() {
JButton b = new JButton();
b.setBackground(Color.red);
b.setBorder(new LineBorder(Color.black, 2));
b.setPreferredSize(new Dimension(600, 10));
panel = new JPanel(new GridLayout(0, 1));
panel.add(b);
panel.setBorder(new TitledBorder(new LineBorder(Color.ORANGE, 1),
"Add Components At Runtime"));
f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(panel, "Center");
f.add(getCheckBoxPanel(), "South");
f.setLocation(200, 200);
f.pack();
f.setVisible(true);
}
private JPanel getCheckBoxPanel() {
checkValidate = new JCheckBox("validate");
checkValidate.setSelected(false);
checkReValidate = new JCheckBox("revalidate");
checkReValidate.setSelected(false);
checkRepaint = new JCheckBox("repaint");
checkRepaint.setSelected(false);
checkPack = new JCheckBox("pack");
checkPack.setSelected(false);
JButton addComp = new JButton("Add New One");
addComp.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JButton b = new JButton();
b.setBackground(Color.red);
b.setBorder(new LineBorder(Color.black, 2));
b.setPreferredSize(new Dimension(600, 10));
panel.add(b);
makeChange();
System.out.println(" Components Count after Adds :" + panel.getComponentCount());
}
});
JButton removeComp = new JButton("Remove One");
removeComp.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
int count = panel.getComponentCount();
if (count > 0) {
panel.remove(0);
}
makeChange();
System.out.println(" Components Count after Removes :" + panel.getComponentCount());
}
});
JPanel panel2 = new JPanel();
panel2.add(checkValidate);
panel2.add(checkReValidate);
panel2.add(checkRepaint);
panel2.add(checkPack);
panel2.add(addComp);
panel2.add(removeComp);
return panel2;
}
private void makeChange() {
if (checkValidate.isSelected()) {
panel.validate();
}
if (checkReValidate.isSelected()) {
panel.revalidate();
}
if (checkRepaint.isSelected()) {
panel.repaint();
}
if (checkPack.isSelected()) {
f.pack();
}
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
AddComponentsAtRuntime makingChanges = new AddComponentsAtRuntime();
}
});
}
}

The blue line (in metal) is the default border used by TitledBorder if none is given explicitly. You need to provide another border if you don't like the default, f.i. an EmptyBorder:
myPanel.setBorder(BorderFactory.createTitledBorder
(BorderFactory.createEmptyBorder(), someTitle));