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Place label for text box above the box and not to the side

As stated in the title i need to move the label for the text box to be above the box and not to the side. attached i have a picutres of what i mean. what i have vs what i want i have tried searching for it but i cannot seem to find the answer im looking for/not exactly sure what to look up. I have tried using JFrame but it made a separate window unless i need to make the entire GUI a JFrame for me to get the result i want?
Also the actionPerformed method has things but it is irrelevant to the question but displays correctly still.
import java.awt.event.\*;
import javax.swing.\*;
import java.text.DecimalFormat;
public class Project4 extends JFrame implements ActionListener {
private JTextArea taArea = new JTextArea("", 30, 20);
ButtonGroup group = new ButtonGroup();
JTextField name = new JTextField(20);
boolean ch = false;
boolean pep = false;
boolean sup = false;
boolean veg = false;
DecimalFormat df = new DecimalFormat("##.00");
double cost = 0.0;
public Project4() {
initUI();
}
public final void initUI() {
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JPanel panel3 = new JPanel();
JPanel panel4 = new JPanel();
JPanel panel5 = new JPanel();
getContentPane().add(panel1, "North");
getContentPane().add(panel2, "West");
getContentPane().add(panel3, "Center");
getContentPane().add(panel4, "East");
panel4.setLayout(new BoxLayout(panel4, BoxLayout.Y_AXIS));
getContentPane().add(panel5, "South");
JButton button = new JButton("Place Order");
button.addActionListener(this);
panel5.add(button);
JButton button2 = new JButton("Clear");
button2.addActionListener(this);
panel5.add(button2);
panel3.add(taArea);
JCheckBox checkBox1 = new JCheckBox("Cheese Pizza") ;
checkBox1.addActionListener(this);
panel4.add(checkBox1);
JCheckBox checkBox2 = new JCheckBox("Pepperoni Pizza");
checkBox2.addActionListener(this);
panel4.add(checkBox2);
JCheckBox checkBox3 = new JCheckBox("Supreme Pizza");
checkBox3.addActionListener(this);
panel4.add(checkBox3);
JCheckBox checkBox4 = new JCheckBox("Vegetarian Pizza");
checkBox4.addActionListener(this);
panel4.add(checkBox4);
JRadioButton radioButton1 = new JRadioButton("Pick Up");
group.add(radioButton1);
radioButton1.addActionListener(this);
panel1.add(radioButton1);
JRadioButton radioButton2 = new JRadioButton("Delivery");
group.add(radioButton2);
radioButton2.addActionListener(this);
panel1.add(radioButton2);
JLabel name_label = new JLabel("Name on Order");
name.addActionListener(this);
panel5.add(name_label);
panel5.add(name);
setSize(600, 300);
setTitle("Pizza to Order");
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent action) {
}
public static void main(String[] args) {
Project4 ex = new Project4();
ex.setVisible(true);
}
}

You can use a nested JPanel with another layout in order to achieve that. I would go with BorderLayout here. You can also other layouts that allow vertical orientation. Visiting the visual guide to Layout Managers will help you spot them.
JLabel name_label = new JLabel("Name on Order");
name.addActionListener(this);
JPanel verticalNestedPanel = new JPanel(new BorderLayout());
verticalNestedPanel.add(name_label, BorderLayout.PAGE_START);
verticalNestedPanel.add(name, BorderLayout.PAGE_END);
panel5.add(verticalNestedPanel);

Why launching does it random?

When i run this program sometimes shows me all buttons, but sometimes only 2 or 3 or 4 or 5 or even just 1.. why is that??
I really do not get it. There should always be 6 buttons, but it doesnt show them. Is there any logical reason?
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class testnet
{
public static void main (String[] args)
{
JFrame frame = new JFrame("Knjigarna");
frame.setVisible(true);
frame.setSize(800,200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
frame.add(panel);
JButton button1 = new JButton("Prikazi vse");
panel.add(button1);
button1.addActionListener (new Action1());
JButton button2 = new JButton("Prikazi knjigo");
panel.add(button2);
button2.addActionListener (new Action2());
JButton button3 = new JButton("Dodaj knjigo");
panel.add(button3);
button3.addActionListener (new Action3());
JButton button4 = new JButton("Brisi knjigo");
panel.add(button4);
button4.addActionListener (new Action4());
JButton button5 = new JButton("Uredi knjigo");
panel.add(button5);
button5.addActionListener (new Action5());
JButton button6 = new JButton("Izhod");
panel.add(button6);
button6.addActionListener (new Action6());
}
static class Action1 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame2 = new JFrame("Pikaz vseh knjig");
frame2.setVisible(true);
frame2.setSize(500,800);
JLabel label = new JLabel("Seznam vseh knjig:");
JPanel panel = new JPanel();
JTextField text1=new JTextField("Naslov: ");
JTextField text2=new JTextField("Avtor: ");
frame2.add(panel);
panel.add(label);
panel.add(text1);
panel.add(text2);
}
}
static class Action2 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame3 = new JFrame("Prikaz knjige");
frame3.setVisible(true);
frame3.setSize(600,300);
JLabel label = new JLabel("Vpisi naslov knjige:");
JPanel panel = new JPanel();
frame3.add(panel);
panel.add(label);
}
}
static class Action3 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame4 = new JFrame("Dodajanje knjige");
frame4.setVisible(true);
frame4.setSize(600,300);
JLabel label = new JLabel("Vpisi podtke o knjigi");
JPanel panel = new JPanel();
frame4.add(panel);
panel.add(label);
}
}
static class Action4 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame5 = new JFrame("Brisanje knjige");
frame5.setVisible(true);
frame5.setSize(600,300);
JLabel label = new JLabel("Vpisi naslov knjige, ki jo zelis brisati");
JPanel panel = new JPanel();
frame5.add(panel);
panel.add(label);
}
}
static class Action5 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame6 = new JFrame("Urejanje knjige");
frame6.setVisible(true);
frame6.setSize(600,300);
JLabel label = new JLabel("Vpisi naslov knjige, ki jo zelis urejati");
JPanel panel = new JPanel();
frame6.add(panel);
panel.add(label);
}
}
static class Action6 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
System.exit(0);
}
}
}

try something with layout. JFrame and or remove managed by inside with a content pane. content pane default layout is BorderLayout. so you need to try border layout stuff.
or you can try this code in you main method
frame.setLayout(new FlowLayout());
this will add component by one by one.
for more about layout you can get in here

This is just a fix and not really an explanation of why the problem is occurring.
Call frame.revalidate() after adding all the buttons.
From the Java Docs,
public Component add(Component comp)
This method
changes layout-related information, and therefore, invalidates the
component hierarchy. If the container has already been displayed, the
hierarchy must be validated thereafter in order to display the added
component.

Swing Number Format Exception

For some reason the AddListener class below doesn't work, and I keep getting a number format exception. Could anyone please tell me the reason for this. It seems to me as if it should work.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class BabyCalculator extends JFrame {
JFrame theFrame = this;
JTextField addField; // Declaring this here so that you can access the variable from other places. MAKE SURE TO NOT DECLARE THIS AGAIN IN THE CONSTRUCTOR
JTextField totalField;
public BabyCalculator() {
//You set this up so that you can refer to the frame using the inner class below.
setDefaultCloseOperation(EXIT_ON_CLOSE);
setName("Baby Calculator");
setLayout(new GridLayout(3, 0));
//add
JLabel addLabel = new JLabel("Amount to add:");
addField = new JTextField(10);
JButton addButton = new JButton("add");
addButton.addActionListener(new AddListener());
//multiply
JLabel multiplyLabel = new JLabel("Amount to multiply:");
JTextField multiplyField = new JTextField(10);
JButton multiplyButton = new JButton("multiply");
//total
JLabel totalLabel = new JLabel("Total");
totalField = new JTextField(10);
totalField.setEditable(false);
JButton stopButton = new JButton("Stop");
stopButton.addActionListener(new StopListener());
//Create Panels
JPanel topRow = new JPanel(new BorderLayout());
JPanel middleRow = new JPanel(new BorderLayout());
JPanel bottomRow = new JPanel(new FlowLayout());
//Add the top Row
topRow.add(addLabel, BorderLayout.WEST);
topRow.add(addField, BorderLayout.CENTER);
topRow.add(addButton, BorderLayout.EAST);
add(topRow);
middleRow.add(multiplyLabel, BorderLayout.WEST);
middleRow.add(multiplyField, BorderLayout.CENTER);
middleRow.add(multiplyButton, BorderLayout.EAST);
add(middleRow);
bottomRow.add(totalLabel);
bottomRow.add(totalField);
bottomRow.add(stopButton);
add(bottomRow);
pack();
setVisible(true);
}
public class AddListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
String addFieldText = addField.getText();
String totalFieldText = totalField.getText();
double addAmount = Double.parseDouble(addFieldText);
double total = Double.parseDouble(totalFieldText);
total += addAmount;
totalField.setText(total + "");
}
}
//end class AddListener
public class StopListener implements ActionListener {//this is an inner class
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(theFrame, "You Clicked the stop button");
}//end class StopListener
}
public static void main(String[] args) {
JFrame newFrame = new BabyCalculator();
}
}
Note: The problem in the code is definitely related to the AddListener. Whenever I click the add button in the GUI I get an exception.

The problem is with the totalFieldText, it's default value is blank, meaning that when you try and convert to a double value, it causes a NumberFormatException
Try giving it a default value of 0, for example
totalField = new JTextField("0", 10);
You might also like to take a look at How to Use Spinners and How to Use Formatted Text Fields which will make your life easier

Change Button to JButton can't fixe it(((

I'm stuck using Button and JButton
expected result.. ( all information working )
http://i.stack.imgur.com/3qX7v.png
and what I have
http://i.stack.imgur.com/a4gao.png
I want to replace this:
Button butRock = new Button("Rock");
butRock.addActionListener(this);
ButtPan.add(butRock);
To This:
BufferedImage buttonIcon = ImageIO.read(new File("rock.jpg"));
JButton butRock = new JButton(new ImageIcon(buttonIcon));
butRock.addActionListener(this);
ButtPan.add(butRock);
I'm stuck because when I replace Button to JButton the program doesn't work properly...when I use this JButton
Question: How to replace the button with picture and that program still work properly...
import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
public class gui extends JFrame implements ActionListener
{
public JLabel JWoL,JWoLPlayer,JWoLPC,JNumWin,JNumLose,JNumTie, logo;
public JLabel JWinT,JLoseT,JTieT, rpsP, rpsC, result;
JPanel LabelsPan;
static final int WINS = 0, LOSSES = 1, DRAWS = 2;
int[] counts = new int[3];
String[] strings = {"| You Win", "| You Lose", "| Draw"};
JLabel[] labels = {JNumWin, JNumLose, JNumTie};
#SuppressWarnings("deprecation")
public static void main(String[] args) throws IOException
{
gui theWindow = new gui();
theWindow.show();
}
private void record(int type)
{
JWoL.setText(strings[type]);
counts[type]++;
labels[type].setText(""+counts[type]);
}
public gui() throws IOException
{
JPanel logo = new JPanel();
logo.setLayout(new GridLayout(1,1));
BufferedImage myPicture = ImageIO.read(new File("logo.jpg"));
JLabel picLabel = new JLabel(new ImageIcon( myPicture ));
add(picLabel);
JPanel ButtPan=new JPanel();
ButtPan.setLayout(new GridLayout(1,3));
BufferedImage buttonIcon = ImageIO.read(new File("rock.jpg"));
JButton butRock = new JButton(new ImageIcon(buttonIcon));
butRock.addActionListener(this);
ButtPan.add(butRock);
Button butPaper = new Button("Paper");
butPaper.addActionListener(this);
ButtPan.add(butPaper);
Button butScissors = new Button("Scissors");
butScissors.addActionListener(this);
ButtPan.add(butScissors);
JWoLPlayer = new JLabel();
JWoLPC = new JLabel();
JWoL= new JLabel();
JLabel rpsPlayer= new JLabel("| Your Choice: ");
JLabel rpsComputer= new JLabel("| Computers Choice: ");
setTitle("| RoPaS GAME |");
LabelsPan=new JPanel();
LabelsPan.setLayout(new GridLayout(3,2));
rpsP = new JLabel();
LabelsPan.add(rpsPlayer);
LabelsPan.add(JWoLPlayer);
rpsC = new JLabel();
LabelsPan.add(rpsComputer);
LabelsPan.add(JWoLPC);
result =new JLabel();
LabelsPan.add(JWoL,"Center");
JPanel WLPan = new JPanel();
WLPan.setLayout(new GridLayout(3, 2));
JWinT = new JLabel("Wins: ");
JLoseT = new JLabel("Losses: ");
JTieT = new JLabel("Ties: ");
WLPan.add(JWinT);
JNumWin = new JLabel();
WLPan.add(JNumWin);
WLPan.add(JLoseT);
JNumLose = new JLabel();
WLPan.add(JNumLose);
WLPan.add(JTieT);
JNumTie = new JLabel();
WLPan.add(JNumTie);
JLabel[] labels1 = {JNumWin, JNumLose, JNumTie};
labels = labels1;
JPanel TwoPanesN1=new JPanel();
TwoPanesN1.setLayout(new BorderLayout());
TwoPanesN1.add(logo,"North");
TwoPanesN1.add(LabelsPan,"West");
TwoPanesN1.add(WLPan,"East");
getContentPane().setLayout(new GridLayout(3,2));
getContentPane().add(ButtPan);
getContentPane().add(TwoPanesN1);
Font fontDisplay = new Font("Arial", Font.BOLD, 16);
JWoL.setFont(fontDisplay);
LabelsPan.setFont(fontDisplay);
setSize(400,250);
setVisible(true);
setResizable(false);
addWindowListener(new WindowAdapter() {public void windowClosing(WindowEvent ev){System.exit(0);}});
}
public void Play(String PlayerChoice)
{
String PCchoice=PCansw();
JWoLPC.setText(PCchoice);
if(PlayerChoice.equals(PCchoice))
record(DRAWS);
else if(PlayerChoice.equals("Rock"))
if(PCchoice.equals("Paper"))
record(LOSSES);
else
record(WINS);
else if(PlayerChoice.equals("Paper"))
if(PCchoice.equals("Scissors"))
record(LOSSES);
else
record(WINS);
else if(PlayerChoice.equals("Scissors"))
if(PCchoice.equals("Rock"))
record(LOSSES);
else
record(WINS);
}
public String PCansw()
{
String rpsPC2="";
int rpsPC=(int)(Math.random( )*3)+1;
if(rpsPC==1)
rpsPC2= "Rock";
else if(rpsPC==2)
rpsPC2= "Paper";
else if(rpsPC==3)
rpsPC2= "Scissors";
return rpsPC2;
}
public void actionPerformed(ActionEvent e)
{
if(e.getActionCommand().equals("Exit"))
System.exit(0);
else
{
JWoLPlayer.setText(e.getActionCommand());
Play(e.getActionCommand());
}
}
}

The problem is that you are using getActionCommand to determine which JButton was clicked but this property is not set by default in Swing. You would have to call
butRock.setActionCommand("Rock");
java.awt.Button automatically uses the label property as the ActionCommand if it not explicitly set. From the docs
If the command name is null (default) then this method returns the label of the button.
Some asides:
Better to avoid mixing heavy & lightweight components and use lightweight components throughout the application.
As your Rock, Paper, Scissors buttons have identical functionality, consider using an Action.
A direct instance JFrame is typically used rather than extending the class
Use Initial Threads
Window#show is deprecated. Use Window#setVisible.
Don't use System.exit - See more here

Java JFrame background color not working

I tried using:
frame1.getContentPane().setBackground(Color.yellow);
But it is not working. Can anyone help me?
import java.awt.*;
import java.awt.Color;
public class PlayGame {
public static void main(String[] args) {
GameFrame frame1 = new GameFrame();
frame1.getContentPane().setBackground(Color.yellow);
// Set Icon
Image icon = Toolkit.getDefaultToolkit().getImage("image/poker_icon.gif");
frame1.setIconImage(icon);
frame1.setVisible(true);
frame1.setSize(600, 700);
frame1.setTitle("Card Game");
// Set to exit on close
frame1.setDefaultCloseOperation(GameFrame.EXIT_ON_CLOSE);
}
}
GameFrame
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class GameFrame extends JFrame implements ActionListener {
private JPanel topPnl, btmPnl, pcPnl, mainPnl;
private JPanel titlePnl, playerPnl, computerPnl;
private JLabel titleLbl, playerLbl, computerLbl;
private JLabel testTextBox1, testTextBox2;
private ImageIcon playerIcon, computerIcon;
//
private JPanel pickCardPnl, pickCardTitlePnl, cardPnl, resultPnl, optionPnl;
private JLabel pickCardTitleLbl;
private JLabel card1Lbl, card2Lbl, card3Lbl, card4Lbl, card5Lbl;
private JLabel resultLbl;
private JButton restartBtn, showCardBtn, exitBtn;
private JButton card1Btn, card2Btn, card3Btn, card4Btn, card5Btn;
private ImageIcon card1Pic, card2Pic, card3Pic, card4Pic, card5Pic;
private JButton playerBtn, computerBtn;
private ImageIcon playerPic;
private String[] card = new String[53];
private String name;
// ArrayInt al;
public GameFrame() {
// a1 = new Array();
//a1.generateRandom();
setCard();
setName();
// Top Panel /////////////////////////////////////
mainPnl = new JPanel(new BorderLayout());
topPnl = new JPanel(new BorderLayout(50, 0));
titlePnl = new JPanel();
pcPnl = new JPanel(new GridLayout(1, 2, 10, 10));
playerPnl = new JPanel(new BorderLayout(10, 10));
computerPnl = new JPanel(new BorderLayout(10, 10));
// Title Panel
titleLbl = new JLabel("Card Game");
titlePnl.add(titleLbl);
// Player Panel
playerIcon = new ImageIcon("image/player.png");
playerLbl = new JLabel(name, playerIcon, JLabel.CENTER);
playerPnl.add(playerLbl, BorderLayout.NORTH);
playerPic = new ImageIcon("image/unknwon.png");
playerBtn = new JButton(playerPic);
playerPnl.add(playerBtn, BorderLayout.CENTER);
playerBtn.setContentAreaFilled(false);
playerBtn.setBorder(BorderFactory.createEmptyBorder());
// Computer Panel
computerIcon = new ImageIcon("image/computer.png");
computerLbl = new JLabel("Computer:", computerIcon, JLabel.CENTER);
computerPnl.add(computerLbl, BorderLayout.NORTH);
playerPic = new ImageIcon("image/back.png");
computerBtn = new JButton(playerPic);
computerPnl.add(computerBtn, BorderLayout.CENTER);
computerBtn.setContentAreaFilled(false);
computerBtn.setBorder(BorderFactory.createEmptyBorder());
pcPnl.add(playerPnl);
pcPnl.add(computerPnl);
// Add panel into Top Panel
topPnl.add(titlePnl, BorderLayout.NORTH);
topPnl.add(pcPnl, BorderLayout.CENTER);
// Bottom Panel /////////////////////////////////////
btmPnl = new JPanel(new BorderLayout());
pickCardPnl = new JPanel(new BorderLayout());
pickCardTitlePnl = new JPanel();
cardPnl = new JPanel(new GridLayout(1, 5, 5, 5));
resultPnl = new JPanel();
optionPnl = new JPanel(new GridLayout(1, 3, 5, 5));
// Pick Card Panel
pickCardTitleLbl = new JLabel("Pick Your Card:");
pickCardPnl.add(pickCardTitleLbl, BorderLayout.NORTH);
card1Pic = new ImageIcon(card[1]);
card1Btn = new JButton(card1Pic);
cardPnl.add(card1Btn);
card1Btn.addActionListener(this);
card2Pic = new ImageIcon(card[2]);
card2Btn = new JButton(card2Pic);
cardPnl.add(card2Btn);
card2Btn.addActionListener(this);
card3Pic = new ImageIcon(card[3]);
card3Btn = new JButton(card3Pic);
cardPnl.add(card3Btn);
card3Btn.addActionListener(this);
card4Pic = new ImageIcon(card[4]);
card4Btn = new JButton(card4Pic);
cardPnl.add(card4Btn);
card4Btn.addActionListener(this);
card5Pic = new ImageIcon(card[5]);
card5Btn = new JButton(card5Pic);
cardPnl.add(card5Btn);
card5Btn.addActionListener(this);
// new ImageIcon(a1.getRandomNumber);
pickCardPnl.add(cardPnl, BorderLayout.CENTER);
card1Btn.setContentAreaFilled(false);
card1Btn.setBorder(BorderFactory.createEmptyBorder());
card2Btn.setContentAreaFilled(false);
card2Btn.setBorder(BorderFactory.createEmptyBorder());
card3Btn.setContentAreaFilled(false);
card3Btn.setBorder(BorderFactory.createEmptyBorder());
card4Btn.setContentAreaFilled(false);
card4Btn.setBorder(BorderFactory.createEmptyBorder());
card5Btn.setContentAreaFilled(false);
card5Btn.setBorder(BorderFactory.createEmptyBorder());
// Result Panel
setCard();
resultLbl = new JLabel("adasdadadasdasdasdasd");
resultPnl.add(resultLbl);
// Option Panel
restartBtn = new JButton("Restart");
optionPnl.add(restartBtn);
restartBtn.addActionListener(this);
showCardBtn = new JButton("Show Cards");
optionPnl.add(showCardBtn);
showCardBtn.addActionListener(this);
exitBtn = new JButton("Exit");
optionPnl.add(exitBtn);
exitBtn.addActionListener(this);
// Add panel into Bottom Panel
btmPnl.add(pickCardPnl, BorderLayout.NORTH);
btmPnl.add(resultPnl, BorderLayout.CENTER);
btmPnl.add(optionPnl, BorderLayout.SOUTH);
//
mainPnl.add(topPnl, BorderLayout.NORTH);
// add(midPNL, BorderLayout.CENTER);
mainPnl.add(btmPnl, BorderLayout.CENTER);
add(mainPnl);
// Menu bar
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu("Game");
menuBar.add(menu);
JMenuItem item3 = new JMenuItem("Change Name");
item3.addActionListener(this);
menu.add(item3);
JMenuItem item = new JMenuItem("Change Card Deck");
item.addActionListener(this);
menu.add(item);
JMenu subMenu = new JMenu("Change BackGround");
subMenu.addActionListener(this);
menu.add(subMenu);
JMenuItem subItem = new JMenuItem("Blue");
subItem.addActionListener(this);
subMenu.add(subItem);
JMenuItem subItem2 = new JMenuItem("Green");
subItem2.addActionListener(this);
subMenu.add(subItem2);
//
menu.addSeparator();
//
JMenuItem item4 = new JMenuItem("Quit");
item4.addActionListener(this);
menu.add(item4);
setJMenuBar(menuBar);
} //End of GameFrame
public void setCard() {
GenRandom g1 = new GenRandom();
g1.GenRandomCard();
int[] allCard = new int[11];
allCard = g1.getAllCard();
for (int i = 1; i <= 10; i++) {
card[i] = "image/card/" + allCard[i] + ".png";
}
}
public void setName() {
// name = JOptionPane.showInputDialog(null, "Please Enter Your Name", "Welcome", JOptionPane.QUESTION_MESSAGE) + ":";
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == card1Btn) {
playerBtn.setIcon(card1Pic);
card1Btn.setEnabled(false);
}
if (e.getSource() == card2Btn) {
playerBtn.setIcon(card2Pic);
card2Btn.setEnabled(false);
}
if (e.getSource() == card3Btn) {
playerBtn.setIcon(card3Pic);
card3Btn.setEnabled(false);
}
if (e.getSource() == card4Btn) {
playerBtn.setIcon(card4Pic);
card4Btn.setEnabled(false);
}
if (e.getSource() == card5Btn) {
playerBtn.setIcon(card5Pic);
card5Btn.setEnabled(false);
}
if (e.getSource() == restartBtn) {
new AePlayWave("sound/jet.wav").start();
JOptionPane.showMessageDialog(null, "Restart Button ");
}
if (e.getSource() == exitBtn) {
/* long start = System.currentTimeMillis();
long end = start + 4 * 1000; // 60 seconds * 1000 ms/sec
while (System.currentTimeMillis() < end) {
// run
new AePlayWave("sound/jet.wav").start();
}*/
System.exit(0);
}
}
}

Since you did not post an SSCCE, I will do it for you. This shows how to change the background color of a JFrame. Starting from this, you can start adding components to the JFrame and see where you go wrong, instead of letting us look at a few hundred lines of code.
import javax.swing.JFrame;
import java.awt.Color;
import java.awt.EventQueue;
public class ColoredFrame {
public static void main( String[] args ) {
EventQueue.invokeLater( new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame( "TestFrame" );
frame.getContentPane().setBackground( Color.PINK );
//frame contains nothing, so set size
frame.setSize( 200, 200 );
frame.setVisible( true );
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
}
} );
}
}

Just put your setVisible(true); at the end of your constructor.
Moreover you had added mainPnl on your JFrame, so changing colour of the JFrame will be useless,
so instead of writing
add(mainPnl);
in your GameFrame class, you better be using
setContentPane(mainPnl);
for frame1.getContentPane().setBackground(Color.YELLOW); to work.
Hope this might help
Regards

You should give background color to JPanel and then use this JPanel in your JFrame rather than giving direct background to your JFrame.

I know this is a very old question, but for others that are looking for the right answer this could also be written as following:
frame1.getContentPane().setBackground(new Color (255,255,102)); //or whatever color you want in the RGB range