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How can I add for JPanel show/hide action to the JButton in implemented ActionListener?

I am trying to understand implemented ActionListener. I couldn't find a way out to add it to JButtons in an othor method. I simply trying to add show and hide action to buttons but I could't. Any help? My code is here. There are 3 colored JPanel and every button should hide or show related color JPanel.
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.Border;
public class ShowHidePanels implements ActionListener {
public static void main(String[] args) {
new ShowHidePanels();
}
public ShowHidePanels() {
JFrame frame = new JFrame();
frame.setLayout(new GridLayout(1, 2));
frame.add(bluePanel());
frame.add(greenPanel());
frame.add(redPanel());
frame.add(buttonPanel());
frame.setSize(950, 600);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public static JPanel greenPanel() {
String greenTitle = "Green Panel";
Border greenBorder = BorderFactory.createTitledBorder(greenTitle);
JPanel greenPanel = new JPanel();
greenPanel.setBorder(greenBorder);
greenPanel.setBackground(new Color(165, 195, 70));
return greenPanel;
}
public static JPanel bluePanel() {
String blueTitle = "Blue Panel";
Border blueBorder = BorderFactory.createTitledBorder(blueTitle);
JPanel bluePanel = new JPanel();
bluePanel.setBorder(blueBorder);
bluePanel.setBackground(new Color(80, 105, 212));
return bluePanel;
}
public static JPanel redPanel() {
String redTitle = "Kirmizi Panel";
Border redBorder = BorderFactory.createTitledBorder(redTitle);
JPanel redPanel = new JPanel();
redPanel.setBorder(redBorder);
redPanel.setBackground(new Color(255, 100, 90));
return redPanel;
}
public static JPanel buttonPanel() {
Border greyBorder = BorderFactory.createTitledBorder("Grey Panel");
JButton b_BlueHide = new JButton("Hide Blue");
JButton b_BlueShow = new JButton("Show Blue");
JButton b_RedHide = new JButton("Hide Red");
JButton b_RedShow = new JButton("Show Red");
JButton b_GreenHide = new JButton("Hide Green");
JButton b_GreenShow = new JButton("Show Green");
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(0, 1));
buttonPanel.setBorder(greyBorder);
buttonPanel.setBackground(new Color(200, 200, 200));
buttonPanel.add(b_BlueHide);
buttonPanel.add(b_BlueShow);
buttonPanel.add(b_GreenHide);
buttonPanel.add(b_GreenShow);
buttonPanel.add(b_RedHide);
buttonPanel.add(b_RedShow);
return buttonPanel;
}
#Override
public void actionPerformed(ActionEvent event) {
}
}

static is not your friend. It has its place and purpose, but this is not one of them. Learn to live without it.
Instead, your methods and components should be instance based (that is, obviously, not static and reliant on a instance of the parent class).
The following example is slightly modified and makes use of a CardLayout to switch the panels, which is a lot more fun then trying to handle z-order issues ;)
Take a look at How to Use CardLayout
import java.awt.BorderLayout;
import java.awt.CardLayout;
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.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.Border;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel implements ActionListener {
private CardLayout cardLayout;
private JPanel contentPane;
public TestPane() {
cardLayout = new CardLayout();
setLayout(new BorderLayout());
contentPane = new JPanel(cardLayout);
contentPane.add(bluePanel(), "blue");
contentPane.add(greenPanel(), "green");
contentPane.add(redPanel(), "red");
add(contentPane);
add(buttonPanel(), BorderLayout.SOUTH);
}
public JPanel greenPanel() {
String greenTitle = "Green Panel";
Border greenBorder = BorderFactory.createTitledBorder(greenTitle);
JPanel greenPanel = new JPanel();
// Demonstration purposes only -----//
greenPanel.setPreferredSize(new Dimension(200, 200));
// ----- Demonstration purposes only //
greenPanel.setBorder(greenBorder);
greenPanel.setBackground(new Color(165, 195, 70));
return greenPanel;
}
public JPanel bluePanel() {
String blueTitle = "Blue Panel";
Border blueBorder = BorderFactory.createTitledBorder(blueTitle);
JPanel bluePanel = new JPanel();
// Demonstration purposes only -----//
bluePanel.setPreferredSize(new Dimension(200, 200));
// ----- Demonstration purposes only //
bluePanel.setBorder(blueBorder);
bluePanel.setBackground(new Color(80, 105, 212));
return bluePanel;
}
public JPanel redPanel() {
String redTitle = "Kirmizi Panel";
Border redBorder = BorderFactory.createTitledBorder(redTitle);
JPanel redPanel = new JPanel();
// Demonstration purposes only -----//
redPanel.setPreferredSize(new Dimension(200, 200));
// ----- Demonstration purposes only //
redPanel.setBorder(redBorder);
redPanel.setBackground(new Color(255, 100, 90));
return redPanel;
}
public JPanel buttonPanel() {
Border greyBorder = BorderFactory.createTitledBorder("Grey Panel");
JButton blue = new JButton("Blue");
JButton red = new JButton("Red");
JButton green = new JButton("Green");
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(0, 1));
buttonPanel.setBorder(greyBorder);
buttonPanel.setBackground(new Color(200, 200, 200));
buttonPanel.add(blue);
buttonPanel.add(green);
buttonPanel.add(red);
blue.addActionListener(this);
green.addActionListener(this);
red.addActionListener(this);
return buttonPanel;
}
#Override
public void actionPerformed(ActionEvent e) {
String cmd = e.getActionCommand();
if ("blue".equalsIgnoreCase(cmd)) {
cardLayout.show(contentPane, "blue");
} else if ("red".equalsIgnoreCase(cmd)) {
cardLayout.show(contentPane, "red");
} else if ("green".equalsIgnoreCase(cmd)) {
cardLayout.show(contentPane, "green");
}
}
}
}
There's a lot of room for simplification and reduction of duplicate workflows, but I'll leave that for you to figure out ;)

How to wait until JDialog is fully created

I need to calculate window decorations somehow. So I override JDialog's constructor. But when I call get_decoration_size() it sometimes returns wrong values. And my thought was: window creates later than get_decoration_size() executes(strange, because both in same thread and in same constructor). So I decided to sleep for a second, and it worked, and now decorations always valid.
My question is: is there a way to "join" to the creating process(wait until window is shown by setVisible(true))? If so, it must be something to replace unsafe_sleep(1000).
package swing.window;
import db.db;
import javax.swing.*;
import java.awt.*;
import static swing.util.*;
import static util.util.unsafe_sleep;
public class calc_decor extends JDialog {
{
//some initializations
setLayout(null);
setResizable(false);
JLabel label = new JLabel("Loading...");
add(label);
setxy(label, 3, 3);
fit(label);
setsize(this, label.getWidth() + 100, label.getHeight() + 100);
window_to_center(this);
setVisible(true);//trying to draw
unsafe_sleep(1000);//without that it looks like get_decoratoin_size()
//is called before setVisible(true)
db.sysdecor = get_decoration_size();//trying to get decorations
dispose();
}
private Dimension get_decoration_size() {
Rectangle window = getBounds();
Rectangle content = getContentPane().getBounds();
int width = window.width - content.width;
int height = window.height - content.height;
return new Dimension(width, height);
}
}

I had to assume a lot to create a runnable example.
Here's the result of your getDecorationSize method. The line didn't print until I closed the JDialog.
java.awt.Dimension[width=16,height=39]
And here's the code I used.
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class JDialogTest implements Runnable {
public static void main(String[] args) {
SwingUtilities.invokeLater(new JDialogTest());
}
private JFrame frame;
#Override
public void run() {
frame = new JFrame("JDialog Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(createMainPanel());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
private JPanel createMainPanel() {
JPanel panel = new JPanel(new BorderLayout());
panel.setBorder(BorderFactory.createEmptyBorder(
150, 100, 150, 100));
panel.setPreferredSize(new Dimension(400, 400));
JButton button = new JButton("Open JDialog");
button.addActionListener(new ButtonListener());
panel.add(button);
return panel;
}
public class ButtonListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
new CalculateDecor(frame, "Spash Screen");
}
}
public class CalculateDecor extends JDialog {
private static final long serialVersionUID = 1L;
public CalculateDecor(JFrame frame, String title) {
super(frame, true);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
setTitle(title);
JPanel panel = new JPanel(new BorderLayout());
panel.setPreferredSize(new Dimension(200, 200));
JLabel label = new JLabel("Loading...");
label.setHorizontalAlignment(JLabel.CENTER);
panel.add(label);
add(panel);
pack();
setLocationRelativeTo(frame);
setVisible(true);
System.out.println(getDecorationSize());
}
private Dimension getDecorationSize() {
Rectangle window = getBounds();
Rectangle content = getContentPane().getBounds();
int width = window.width - content.width;
int height = window.height - content.height;
return new Dimension(width, height);
}
}
}

How to change JPlane position?

I tried create some window application. I have container which consist a JFrame and two JPanel (white square and red square. The last square inside white square).
I want change position red square ( any place on my work window( for example, left or right side)). I tried do it, but i didn't have success.
Could you help me?
It's my code)
import java.awt.*;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class main_window extends JFrame {
public static void main(String\[\] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setBackground(Color.black);
frame.getContentPane().setLayout(new GridLayout(1, 1));
JPanel panel = new JPanel();
panel.setBackground(Color.WHITE);
frame.getContentPane().add(panel);
JPanel panel_1 = new JPanel();
panel_1.setPreferredSize(new Dimension(200, 200));
panel_1.setBackground(Color.red);
panel.add(panel_1);
frame.setSize(800,800);
frame.setVisible(true);
}
}

GridBagLayout will give you the greatest amount of control over the layout itself.
For example...
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setBackground(Color.WHITE);
setLayout(new GridBagLayout());
JPanel pane = new JPanel() {
#Override
public Dimension getPreferredSize() {
return new Dimension(50, 50);
}
};
pane.setBackground(Color.RED);
GridBagConstraints gbc = new GridBagConstraints();
gbc.weightx = 1;
gbc.weighty = 1;
// Left
//gbc.anchor = GridBagConstraints.WEST;
// Right
//gbc.anchor = GridBagConstraints.EAST;
// Top
//gbc.anchor = GridBagConstraints.NORTH;
// Bottom
//gbc.anchor = GridBagConstraints.SOUTH;
// Top/left
//gbc.anchor = GridBagConstraints.NORTHWEST;
// Top/Right
//gbc.anchor = GridBagConstraints.NORTHEAST;
// Bottom/left
//gbc.anchor = GridBagConstraints.SOUTHHWEST;
// Bottom/Right
//gbc.anchor = GridBagConstraints.SOUTHEAST;
// Middle
gbc.anchor = GridBagConstraints.CENTER;
add(pane, gbc);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
}
}
It's also the most complex layout manager, so it might take some time and experimentation to get it just right.
Start by having a look at How to Use GridBagLayout

You can use FlowLayout to control the position of the red square.I have set layout to the outer panel with white background to control the position of the inside panel panel_1 which is the red square.Check my answer.
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setBackground(Color.black);
JPanel panel = new JPanel();
panel.setBackground(Color.WHITE);
frame.getContentPane().add(panel);
JPanel panel_1 = new JPanel();
panel_1.setPreferredSize(new Dimension(200, 200));
panel_1.setBackground(Color.red);
panel.add(panel_1);
//FlowLayout.RIGHT, LEFT, CENTER
panel.setLayout(new FlowLayout(FlowLayout.RIGHT));
frame.setSize(800,800);
frame.setVisible(true);

You need to perform some action in order to move the square e.g. I have added a button in my code which when clicked, will cause the square to move. For the button to perform some action, you need to implement ActionListener. As you can see in the actionPerformed method, I am generating random x and y coordinates of the top left corner of the rectangle and setting new coordinates by using the method, setBounds. Note that I have maintained the same width and height of the rectangle when it is moved to new coordinates.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class MainWindow extends JFrame implements ActionListener {
JPanel panel, panel_1;
JButton btnMoveSquare;
Random random;
MainWindow() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
getContentPane().setBackground(Color.black);
getContentPane().setLayout(new GridLayout(1, 1));
panel = new JPanel();
panel.setBackground(Color.WHITE);
getContentPane().add(panel);
panel_1 = new JPanel();
panel_1.setPreferredSize(new Dimension(200, 200));
panel_1.setBackground(Color.red);
panel.add(panel_1);
btnMoveSquare = new JButton("Move Square");
btnMoveSquare.addActionListener(this);
panel.add(btnMoveSquare);
setSize(800, 800);
random = new Random();
}
#Override
public void actionPerformed(ActionEvent e) {
int x = random.nextInt(800);
int y = random.nextInt(800);
panel_1.setBounds(x, y, panel_1.getWidth(), panel_1.getHeight());
}
public static void main(String[] args) {
new MainWindow().setVisible(true);
}
}
Feel free to comment if you have any doubt with the code.

GridBagLayout and drawing

I'm making a small game and at the beginning i want to have JCheckBox for choosing the language(after that they are few more of them for setting the game) and above that a jlabel with picture with name of the game OR draw an image there, the problem is that i dont know any other way how to center the panel with checkboxes then to use GridBagLayout and when i use this, i cannot draw anything to the frame, id like to also remove those grey lines around the checkboxes if its possible, appreciate any help, thanks.
This is my second question here and i cant add images yet so here is a link to the picture :
here is code for the frame
private GamePlan plan;
private JFrame frame;
private String language;
private JPanel panel;
private JCheckBox englishBox;
private JCheckBox germanBox;
public Settings(GamePlan plan){
this.plan = plan;
frame = new JFrame();
frame.setSize(600, 500);
frame.setLocation(200, 200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridBagLayout());
frame.setResizable(false);
frame.setVisible(true);
panel = new JPanel(new GridLayout(2, 1));
englishBox = new JCheckBox("English", false);
germanBox = new JCheckBox("German", false);
englishBox.addActionListener(new EnglishLanguage());
germanBox.addActionListener(new GermanLanguage());
panel.add(englishBox);
panel.add(germanBox);
englishBox.setOpaque(false);
germanBox.setOpaque(false);
panel.setOpaque(false);
frame.add(panel);
frame.getContentPane().setBackground(new Color(216,252,202));
}

" the problem is that i dont know any other way how to center the panel with checkboxes then to use GridBagLayout and when i use this, i cannot draw anything to the frame"
I can't really tell what you're doing wrong without a complete example. I don't even see where you're trying to add the image. But don't try and draw on the frame. Draw on a JPanel instead.
Here is an example you may be able to gain some insight from.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridBagLayout;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.TitledBorder;
public class ImageByDrawing {
public ImageByDrawing() {
ImagePanel imagePanel = new ImagePanel();
imagePanel.setBorder(new TitledBorder("Drawn Image onto JPanel"));
JCheckBox germanBox = new JCheckBox("German");
germanBox.setOpaque(false);
JCheckBox englishBox = new JCheckBox("English");
englishBox.setOpaque(false);
JPanel boxPanel = new JPanel();
boxPanel.setBorder(new TitledBorder("JPanel with default FlowLayout"));
boxPanel.setOpaque(false);
boxPanel.add(germanBox);
boxPanel.add(englishBox);
JPanel centerPanel = new JPanel(new BorderLayout());
centerPanel.add(imagePanel, BorderLayout.CENTER);
centerPanel.add(boxPanel, BorderLayout.SOUTH);
centerPanel.setBorder(new TitledBorder("JPanel with BorderLayout"));
centerPanel.setOpaque(false);
JPanel mainPanel = new JPanel(new GridBagLayout());
mainPanel.add(centerPanel);
mainPanel.setBorder(new TitledBorder("JPanel with GridBagLayout"));
mainPanel.setBackground(new Color(216,252,202));
JFrame frame = new JFrame();
frame.add(mainPanel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(600, 600);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public class ImagePanel extends JPanel {
BufferedImage img;
int dWidth;
int dHeight;
public ImagePanel() {
try {
img = ImageIO.read(getClass().getResource("/resources/stackblack.jpg"));
dWidth = img.getWidth();
dHeight = img.getHeight();
} catch (IOException ex) {
Logger.getLogger(ImageByDrawing.class.getName()).log(Level.SEVERE, null, ex);
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(img, 0, 0, img.getWidth(), img.getHeight(), this);
}
#Override
public Dimension getPreferredSize() {
return (img == null) ? new Dimension(300, 300) : new Dimension(dWidth, dHeight);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable(){
public void run() {
new ImageByDrawing();
}
});
}
}
Also I don't know why you prefer to draw the image. The same can be easily done with a JLabel and ImageIcon
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridBagLayout;
import javax.swing.ImageIcon;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.TitledBorder;
public class ImageByDrawing {
public ImageByDrawing() {
ImageIcon icon = new ImageIcon(getClass().getResource("/resources/stackblack.jpg"));
JLabel label = new JLabel(icon);
label.setBorder(new TitledBorder("JLabel with ImageIcon"));
JCheckBox germanBox = new JCheckBox("German");
germanBox.setOpaque(false);
JCheckBox englishBox = new JCheckBox("English");
englishBox.setOpaque(false);
JPanel boxPanel = new JPanel();
boxPanel.setBorder(new TitledBorder("JPanel with default FlowLayout"));
boxPanel.setOpaque(false);
boxPanel.add(germanBox);
boxPanel.add(englishBox);
JPanel centerPanel = new JPanel(new BorderLayout());
centerPanel.add(label, BorderLayout.CENTER);
centerPanel.add(boxPanel, BorderLayout.SOUTH);
centerPanel.setBorder(new TitledBorder("JPanel with BorderLayout"));
centerPanel.setOpaque(false);
JPanel mainPanel = new JPanel(new GridBagLayout());
mainPanel.add(centerPanel);
mainPanel.setBorder(new TitledBorder("JPanel with GridBagLayout"));
mainPanel.setBackground(new Color(216, 252, 202));
JFrame frame = new JFrame();
frame.add(mainPanel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(600, 600);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ImageByDrawing();
}
});
}
}
The last part of your question, as #Jere pointed out you can use setFocusPainted for the check box germanBox.setFocusPainted(false);

Random circles JAVA

I am trying to create a GUI that will take in the number of circles to draw, and draw them in drawPanel with random locations/sizes. On my actionListener, when I try to draw the circle, it gives me red lines on my drawOval
1st class:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JTextArea;
/**
*
* #author Chris
*
*/
public class CirclesPanel extends JPanel{
private JButton draw, clear;
private JTextArea textArea;
private JPanel panel, drawPanel, buttonPanel;
private int count;
/**constructor
* builds the frame
*/
public CirclesPanel(){
//creates buttons and textArea
draw = new JButton("Draw");
clear = new JButton("Clear");
textArea = new JTextArea(1,10);
textArea.setBorder(BorderFactory.createTitledBorder("Circles"));
//creats panel
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
setPreferredSize(new Dimension(620, 425));
//creates subpanel drawPanel
JPanel drawPanel = new JPanel();
drawPanel.setPreferredSize(new Dimension(450,400));
drawPanel.setBackground(Color.BLACK);
//creates subpanel buttonPanel
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(3,1));
//adds all the content to the frame
add(panel);
add(buttonPanel, BorderLayout.WEST);
add(drawPanel, BorderLayout.EAST);
buttonPanel.add(textArea);
buttonPanel.add(draw);
buttonPanel.add(clear);
//reads if the draw button is clicked
draw.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
count =Integer.parseInt(textArea.getText());//takes the count in
repaint();//repaints the picture to add the circles
}
});
//reads if the clear button is clicked
clear.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
count=0;//sets the count to 0 so nothing is painted
repaint();//repaints the window
}
});
}
/**Paint component
* draws the random circles
*/
public void paintComponent(Graphics g) {
Random generator = new Random();
int x, y, diameter;
for(int i = 0; i < count; i++){ //loop that takes the count and does this "x" times
g.setColor(Color.BLUE);//sets color to blue
x = generator.nextInt(90);//random location for x
y = generator.nextInt(90);//random location for y
diameter = generator.nextInt(30);//random size
g.fillOval(x, y, diameter, diameter);//draws the circle
}
}
}
2nd class
import javax.swing.JFrame;
public class Circles {
public static void main(String[]args){
JFrame frame = new JFrame("Cicles HW9");
frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new CirclesPanel());
frame.pack();
frame.setVisible(true);
}
}

So in your, I did little addition, first of all, I made the whole program in one class(CIRLCES PANEL), IF You want to use the second class, you can use it....
Problem is coming, your program is not the reading the ActionPerformed method for the drawing, means it is not located with the button, now I directly added it with your button(DRAW), now whenever you click on the button, it automatically reads the your textArea value, and draw your circles. I made your text area FINAL, So you can use it anywhere......
Now things that you need to do----
- this program is drawing circle on the whole frame, means not on your drawing Panel, you need to set the values, so it will draw on your draw panel area
- Also you need to add color for your oval, because it will either draw black color circle, which you will not able to see.....
and also one thing I forget to mentioned you, is that your, you also need to add code for your clear method...
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JTextArea;
public class CirclesPanel extends JPanel{
private JButton draw, clear;
private JTextArea textArea;
private JPanel panel, drawPanel, buttonPanel;
private int count;
public CirclesPanel(){
JButton draw = new JButton("Draw");
JButton clear = new JButton("Clear");
final JTextArea textArea = new JTextArea(1,10);
textArea.setBorder(BorderFactory.createTitledBorder("Circles"));
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
setPreferredSize(new Dimension(620, 425));
JPanel drawPanel = new JPanel();
drawPanel.setPreferredSize(new Dimension(450,400));
drawPanel.setBackground(Color.BLACK);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(3,1));
add(panel);
add(buttonPanel, BorderLayout.WEST);
add(drawPanel, BorderLayout.EAST);
buttonPanel.add(textArea);
buttonPanel.add(draw);
buttonPanel.add(clear);
draw.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
count =Integer.parseInt(textArea.getText());
repaint();
}
});
}
public void paintComponent(Graphics g) {
Random generator = new Random();
int x, y, diameter;
for(int i = 0; i < count; i++){
x = generator.nextInt(90);
y = generator.nextInt(90);
diameter = generator.nextInt(30);
g.drawOval(x, y, diameter, diameter);
}
}
}

What you want to do is drawing some random circles on the drawPanel when button clicked. I write you a simplified version to show how things work.
I only keep the drawButton and paintPanel to keep things simple.
public class PaintFrame extends JFrame {
private JPanel content = new JPanel();
private JButton drawButton = new JButton("Draw");
private PaintPanel paintPanel = new PaintPanel();
public PaintFrame() {
getContentPane().add(content);
content.setLayout(new BorderLayout());
drawButton.setSize(100, 500);
drawButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// drawButton is fired, repaint the paintPanel
paintPanel.repaint();
}
});
content.add(drawButton, BorderLayout.WEST);
content.add(paintPanel, BorderLayout.CENTER);
}
}
You need a new class extending the JPanel and override the paintComponent method to do the paint job for you. This makes sure you are drawing on the panel.
class PaintPanel extends JPanel {
public PaintPanel() {
setSize(500, 500);
setBackground(Color.BLACK);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Random random = new Random();
g.setColor(Color.WHITE);
// draw 5 random circles
int count = 5;
for (int i = 0; i < count; i++) {
g.drawOval(random.nextInt(250), random.nextInt(250),
random.nextInt(250), random.nextInt(250));
}
}
}
Main class
public class DrawMain {
public static void main(String[] args) {
JFrame frame = new PaintFrame();
frame.setDefaultCloseOperation(PaintFrame.EXIT_ON_CLOSE);
frame.setSize(600, 500);
frame.setVisible(true);
}
}