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JPanels, use listener to change size

I am trying to do a JPanel that could change its size each time a click on a button. My approach to it has been to create 2 different panel with different size each. Once clicked one would became visible, and the other one invisible. SO far I have managed to make the first one invisible, but i am stuck there. Is my approach any good? What Am i missing? Here the code...
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class GrowAndShrinkSquareGUI {
JFrame frame;
SquareDrawPanel greenPanel;
SquareDrawPanel greenPanel2;
public class SquareDrawPanel extends JPanel {
int locationX;
int locationY;
int width;
int height;
SquareDrawPanel(int x, int y, int w, int h) {
locationX = x;
locationY = y;
width = w;
height = h;
}
public void paintComponent(Graphics g) {
g.setColor(Color.green);
g.fillRect(locationX, locationY, width, height);
}
}
public class growAndShrinkListener implements ActionListener {
JButton button;
public growAndShrinkListener() {
JButton button = new JButton("Click me to grow the Square");
frame.add(button, BorderLayout.NORTH);
button.addActionListener(this);}
#Override
public void actionPerformed(ActionEvent e) {
System.out.print("clicked");
greenPanel.setVisible(false);
greenPanel2.setVisible(true);
}}
public static void main(String[] args) {
GrowAndShrinkSquareGUI test = new GrowAndShrinkSquareGUI();
test.go();
}
public void go() {
frame = new JFrame();
frame.setSize(500, 500);
frame.setVisible(true);
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
drawPanel(greenPanel);
drawPanel(greenPanel2);
growAndShrinkListener button = new growAndShrinkListener();
//addButton(CreateJButton());
}
private JPanel createRectPanel(int x, int y) {
greenPanel = new SquareDrawPanel(x, y, 100, 100);
return greenPanel;
}
private JPanel createRectPanel2(int x, int y) {
greenPanel2 = new SquareDrawPanel(x, y, 200, 200);
return greenPanel2;
}
private void drawPanel(JPanel panel) {
panel = createRectPanel(setLocationX(), setLocationY());
frame.add(panel, BorderLayout.CENTER); // DoesNot run properly
}
private int setLocationX() {
int centeredX = frame.getWidth() / 2 - 50;
return centeredX;
}
private int setLocationY() {
int centeredY = frame.getHeight() / 2 - 75;
return centeredY;
}
}

public class CustomFrame extends JFrame implements ActionListener
{
//Creating an object of this class shows a frame which toggles
//between these two sizes on a button click
private static final Dimension FIRST_SIZE = new Dimension(200, 200);
private static final Dimension SECOND_SIZE = new Dimension(400, 400);
public CustomFrame()
{
//Add a button to the frame and register an action listener
//to the current object
JButton button = new JButton("Change size");
button.addActionListener(this);
getContentPane().add(button);
//Make the frame visible
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent ae)
{
//This gets executed when the button is clicked
//
//We're setting the size to a new value;
//first, we fetch the current size and
//check if it's equal to the first size
setSize(getSize().equals(FIRST_SIZE)
//If so, set the frame to the second size
? SECOND_SIZE
//In all other cases, make the frame's
//size the value of FIRST_SIZE
: FIRST_SIZE);
}
}

Java GUI paintcomponent (newbie)

Thanks for the help. The objects are all showing now.
But I ran into a new problem. Im trying to use a For loop to draw 10 copys of the same box with a little space in between so they don't just stack in the same position.
But for some reason they keep getting painted on top of eachother and in the center instead of starting at x = 20...
import java.awt.*;
import javax.swing.*;
public class CarWashPanel extends JPanel {
public int i;
public int x = 20;
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.black);
for (i=0; i < 10; i++){
g.fillRoundRect(x, 10, 50, 100, 55, 25);
x = x + 10;
}
}
#Override
public Dimension getPreferredSize() {
return new Dimension(500, 150);
}
}
//
I'm trying to add graphics in my CarWashPanel class to I want to add to my GUI. I've read some tutorials and other questions but I can't figure out what i'm doing wrong.
The buttons and label that i've added to the GUI show up just fine but when I add something to my CarWashPanel it doesn't show up in the GUI.
I feel like I need to tell my GUI to add all elements from the CarWashPanel but I'm not sure how.
public class Main {
public static void main(String[] args) {
GUI g = new GUI();
}
}
import javax.swing.*;
import java.awt.*;
public class GUI extends JFrame {
private JTextField t1 = new JTextField(2);
private JLabel l1 = new JLabel("enter position");
private JButton b1 = new JButton("new customer");
private JButton b2 = new JButton("wash car");
public GUI() {
setDefaultCloseOperation (
JFrame.EXIT_ON_CLOSE );
add(l1);
add(t1);
add(b1);
add(b2);
setTitle("Carwash");
setSize(500, 200);
setVisible(true);
setLayout(new FlowLayout());
add(new CarWashPanel());
}
}
public class Carwash {
private boolean[] positions = new boolean[10];
private int washing = 10;
public void addCar(int p) {
positions[p] = true;
}
public void removeCar(int p) {
positions[p] = false;
}
public boolean[] getPositions() {
return positions;
}
public int getWashing() {
return washing;
}
}
import java.awt.*;
import javax.swing.*;
public class CarWashPanel extends JPanel {
public CarWashPanel(){
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.black);
g.fillRoundRect(150, 50, 100, 100, 50, 25);
}
}

It's very often issue. You are calling setVisible before you are adding your components. Add your components on CarWashPanel, add CarWashPanel on JFrame and then call setVisible. Also, remove this line: setLayout(new FlowLayout()); - FlowLayout is default layout for JPanel (CarWashPanel in your case) and this makes it sufficient.
Your code should look something like this:
import javax.swing.*;
import java.awt.*;
public class Main {
public static void main(String[] args) {
SwingUtilities.invokeLater(GUI::new);
}
public static class GUI extends JFrame {
private JTextField t1 = new JTextField(2);
private JLabel l1 = new JLabel("enter position");
private JButton b1 = new JButton("new customer");
private JButton b2 = new JButton("wash car");
CarWashPanel carWashPanel = new CarWashPanel();
public GUI() {
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
carWashPanel.add(l1);
carWashPanel.add(t1);
carWashPanel.add(b1);
carWashPanel.add(b2);
add(carWashPanel,BorderLayout.CENTER);
setTitle("Carwash");
pack();
setVisible(true);
}
}
public class Carwash {
private boolean[] positions = new boolean[10];
private int washing = 10;
public void addCar(int p) {
positions[p] = true;
}
public void removeCar(int p) {
positions[p] = false;
}
public boolean[] getPositions() {
return positions;
}
public int getWashing() {
return washing;
}
}
public static class CarWashPanel extends JPanel {
public CarWashPanel() {
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.black);
g.fillRoundRect(150, 50, 100, 100, 50, 25);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(500, 200);
}
}
}
Other sidenotes:
Don't call setSize for JFrame, call pack. Rather override getPreferredSize for JPanel and return some dimensions.
Avoid extending your class with JFrame unless you want to define new methods or override existing ones.

If you don't need to add things dynamically the best thing to do is call setVisible(true) after you've added all your components.
However, if you want to add things after the frame is visible you can do so and then call the frame's revalidate() method to cause it to redraw.
Secondly I'd recommend you set the layout before you add any components.

JFrame with custom border not showing controls

I'm trying to make my own custom border, and I have done this through overriding the paint function in the JFrame. The problem which I have run into, is the fact that paint is being called after the constructor, causing it to paint the window over my controls. Because of this, my table only appears when I happen to click on where it is in the JFrame. I was wondering if there is a way to make the paint function happen before my constructor, or if there is a better way to create a custom border. Here is my code:
public class GuiMain extends JFrame {
int posX=0, posY=0;
JTable serverList;
public GuiMain()
{
this.setUndecorated(true);
this.setLayout(new GridBagLayout());
serverList = new JTable(Variables.servers, Variables.serversHeader);
add(serverList);
this.addMouseListener(new MouseAdapter(){
public void mousePressed(MouseEvent e)
{
posX = e.getX();
posY = e.getY();
}
});
this.addMouseMotionListener(new MouseAdapter(){
public void mouseDragged(MouseEvent evt)
{
if(posY <= 20) {
setLocation(evt.getXOnScreen()-posX, evt.getYOnScreen()-posY);
}
}
});
}
public void paint(Graphics g)
{
g.setColor(new Color(100, 100, 100));
g.fillRect(0, 0, Main.width, Main.height);
g.setColor(new Color(70, 70, 70));
g.fillRect(0, 0, Main.width, 20);
}
}
Any help is appreciated! Thanks!

You know that it is not the safest thing to do, overriding paint(...) of a top-level window. What type of "border" are you trying to create? Where is your call to super.paint(g);? Myself, I'd create my own class that extended the AbstractBorder class, and then would use that Border on a JPanel that is the JFrame's contentPane.
For example,
import java.awt.*;
import java.awt.geom.Point2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.border.AbstractBorder;
#SuppressWarnings("serial")
public class FrameEg extends JPanel {
public static final String FRAME_URL_PATH = "http://th02.deviantart.net/"
+ "fs70/PRE/i/2010/199/1/0/Just_Frames_5_by_ScrapBee.png";
public static final int INSET_GAP = 120;
private BufferedImage frameImg;
private BufferedImage smlFrameImg;
public FrameEg() {
try {
URL frameUrl = new URL(FRAME_URL_PATH);
frameImg = ImageIO.read(frameUrl);
final int smlFrameWidth = frameImg.getWidth() / 2;
final int smlFrameHeight = frameImg.getHeight() / 2;
smlFrameImg = new BufferedImage(smlFrameWidth, smlFrameHeight,
BufferedImage.TYPE_INT_ARGB);
Graphics g = smlFrameImg.getGraphics();
g.drawImage(frameImg, 0, 0, smlFrameWidth, smlFrameHeight, null);
g.dispose();
int top = INSET_GAP;
int left = top;
int bottom = top;
int right = left;
Insets insets = new Insets(top, left, bottom, right);
MyBorder myBorder = new MyBorder(frameImg, insets);
JTextArea textArea = new JTextArea(50, 60);
textArea.setWrapStyleWord(true);
textArea.setLineWrap(true);
for (int i = 0; i < 300; i++) {
textArea.append("Hello world! How is it going? ");
}
setLayout(new BorderLayout(1, 1));
setBackground(Color.black);
Dimension prefSize = new Dimension(frameImg.getWidth(),
frameImg.getHeight());
JPanel centerPanel = new MyPanel(prefSize);
centerPanel.setBorder(myBorder);
centerPanel.setLayout(new BorderLayout(1, 1));
centerPanel.add(new JScrollPane(textArea), BorderLayout.CENTER);
MyPanel rightUpperPanel = new MyPanel(new Dimension(smlFrameWidth,
smlFrameHeight));
MyPanel rightLowerPanel = new MyPanel(new Dimension(smlFrameWidth,
smlFrameHeight));
top = top / 2;
left = left / 2;
bottom = bottom / 2;
right = right / 2;
Insets smlInsets = new Insets(top, left, bottom, right);
rightUpperPanel.setBorder(new MyBorder(smlFrameImg, smlInsets));
rightUpperPanel.setLayout(new BorderLayout());
rightLowerPanel.setBorder(new MyBorder(smlFrameImg, smlInsets));
rightLowerPanel.setBackgroundImg(createBackgroundImg(rightLowerPanel
.getPreferredSize()));
JTextArea ruTextArea1 = new JTextArea(textArea.getDocument());
ruTextArea1.setWrapStyleWord(true);
ruTextArea1.setLineWrap(true);
rightUpperPanel.add(new JScrollPane(ruTextArea1), BorderLayout.CENTER);
JPanel rightPanel = new JPanel(new GridLayout(0, 1, 1, 1));
rightPanel.add(rightUpperPanel);
rightPanel.add(rightLowerPanel);
rightPanel.setOpaque(false);
add(centerPanel, BorderLayout.CENTER);
add(rightPanel, BorderLayout.EAST);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
private BufferedImage createBackgroundImg(Dimension preferredSize) {
BufferedImage img = new BufferedImage(preferredSize.width,
preferredSize.height, BufferedImage.TYPE_INT_ARGB);
Point2D center = new Point2D.Float(img.getWidth()/2, img.getHeight()/2);
float radius = img.getWidth() / 2;
float[] dist = {0.0f, 1.0f};
Color centerColor = new Color(100, 100, 50);
Color outerColor = new Color(25, 25, 0);
Color[] colors = {centerColor , outerColor };
RadialGradientPaint paint = new RadialGradientPaint(center, radius, dist, colors);
Graphics2D g2 = img.createGraphics();
g2.setPaint(paint);
g2.fillRect(0, 0, img.getWidth(), img.getHeight());
g2.dispose();
return img;
}
private static void createAndShowGui() {
FrameEg mainPanel = new FrameEg();
JFrame frame = new JFrame("FrameEg");
frame.setUndecorated(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.setResizable(false);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
#SuppressWarnings("serial")
class MyPanel extends JPanel {
private Dimension prefSize;
private BufferedImage backgroundImg;
public MyPanel(Dimension prefSize) {
this.prefSize = prefSize;
}
public void setBackgroundImg(BufferedImage background) {
this.backgroundImg = background;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (backgroundImg != null) {
g.drawImage(backgroundImg, 0, 0, this);
}
}
#Override
public Dimension getPreferredSize() {
return prefSize;
}
}
#SuppressWarnings("serial")
class MyBorder extends AbstractBorder {
private BufferedImage borderImg;
private Insets insets;
public MyBorder(BufferedImage borderImg, Insets insets) {
this.borderImg = borderImg;
this.insets = insets;
}
#Override
public void paintBorder(Component c, Graphics g, int x, int y, int width,
int height) {
g.drawImage(borderImg, 0, 0, c);
}
#Override
public Insets getBorderInsets(Component c) {
return insets;
}
}
Which would look like so:

Do I actually call the paintComponent method I make when creating a rectangle in Java?

This is my current RectangleComponent class and I add it to a panel in my main JFrame but it never appears. I thought it wasn't drawing so I decided to call the paintComponent method in the Rectangle's constructor, and after sorting through 4-5 nullPointerExceptions, nothing has changed. I've read multiple guides on how to draw rectangles and I have seen multiple code examples, but I can never get the panels to work with more than one JComponent. If you could, please take a brief look at my code and see if you can devise a solution.
Thank you for your time. Also listed is the Frame I call the rectangle constructor in.
public class GameFrame extends JFrame
{
private SpellBarComponent bar;
private JPanel mainPanel = new JPanel();
private JPanel buttonPanel = new JPanel();
private JPanel healthPanel = new JPanel();
Color green = new Color(29, 180, 29);
Color red = new Color(255, 0, 0);
private RectangleComponent life;
private RectangleComponent death;
private JFrame frame = new JFrame();
public GameFrame(char x)
{
frame.setSize(1024, 768);
frame.setTitle("Game");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
FlowLayout layout = new FlowLayout();
createPanels(x);
healthPanel.setLayout(layout);
buttonPanel.setLayout(layout);
mainPanel.setLayout(layout);
frame.getContentPane().add(mainPanel);
frame.pack();
repaint();
}
public RectangleComponent getLife()
{
return life;
}
private void createHealth()
{
life = new RectangleComponent(green, healthPanel);
death = new RectangleComponent(red, healthPanel);
}
private void createPanels(char x)
{
add(healthPanel);
pack();
createBar(x);
createHealth();
mainPanel.add(buttonPanel);
mainPanel.add(healthPanel);
healthPanel.add(death);
healthPanel.add(life);
buttonPanel.add(bar.getSpell1());
buttonPanel.add(bar.getSpell2());
buttonPanel.add(bar.getSpell3());
add(mainPanel);
}
private void createBar(char x)
{
bar = new SpellBarComponent(x, mainPanel);
}
}
public class RectangleComponent extends JComponent
{
Color color;
int width;
int height = 18;
RoundRectangle2D roundedRectangle;
private JPanel panel;
public RectangleComponent(Color color, JPanel panel)
{
this.panel = panel;
this.color = color;
paintComponent(panel.getGraphics());
}
public void paintComponent(Graphics g)
{
Graphics2D graphics2 = (Graphics2D) g;
width = 125;
roundedRectangle = new RoundRectangle2D.Float(10, 10, width, height, 10, 10);
graphics2.setPaint(color);
graphics2.fill(roundedRectangle);
graphics2.draw(roundedRectangle);
}
public void subtractLife(int amount)
{
width -= amount;
roundedRectangle.setRoundRect(10, 10, width, height, 10, 10);
repaint();
}
}

In order for your Swing Application to work as expected, there are many a things you need to keep in mind. There are always certain steps that one must follow in order to escape certain hurdles, that might can arise, since you coded in the wrong way. For this stick to the basics of Swing Programming Strictly, and follow them.
Like as mentioned by #HovercraftFullOfEels , you calling to your
Graphics directly, which one should never do.
Secondly, look at your GameFrame() constructor, you set it to
visible, even before you had added any components to it and much
before it's real size has been established
Such loop holes inside your coding might can give rise to many a headaches, as you sit down to write huge programs, so better to be on the safe road from the beginning, then to curse yourself at the later stage. As they say Prevention is better than Cure.
Now coming to your program, you missed the main thingy, since you failed to specify the size of your CustomComponent i.e. JComponent, hence you are not been able to see it on your screen. As you extends a JCompoent to your class, make it a customary habbit to override it's getPreferredSize(), in the same manner you override it's paintComponent(...) method.
Have a look at this small program, I had crafted for you, might be this be able to help you out, to understand the logic a bit more.
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.RoundRectangle2D;
import javax.swing.*;
public class CustomPainting {
private RectangleComponent life;
private RectangleComponent death;
private void createAndDisplayGUI() {
JFrame frame = new JFrame("Custom Painting");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
JPanel centerPanel = new JPanel();
centerPanel.setLayout(new GridLayout(0, 2, 5, 5));
// Specifying the WIDTH, HEIGHT and Colour for this JComponent.
life = new RectangleComponent(Color.GREEN.darker(), 20, 20);
death = new RectangleComponent(Color.RED.darker(), 20, 20);
centerPanel.add(life);
centerPanel.add(death);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout(FlowLayout.LEFT, 5, 5));
JButton incLifeButton = new JButton("INCREASE LIFE");
incLifeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
life.addLife(1);
}
});
JButton decLifeButton = new JButton("DECREASE LIFE");
decLifeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
life.subtractLife(1);
}
});
JButton incDeathButton = new JButton("INCREASE DEATH");
incDeathButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
death.addLife(1);
}
});
JButton decDeathButton = new JButton("DECREASE DEATH");
decDeathButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
death.subtractLife(1);
}
});
buttonPanel.add(incLifeButton);
buttonPanel.add(decLifeButton);
buttonPanel.add(incDeathButton);
buttonPanel.add(decDeathButton);
frame.getContentPane().add(centerPanel, BorderLayout.CENTER);
frame.getContentPane().add(buttonPanel, BorderLayout.PAGE_END);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String\u005B\u005D args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new CustomPainting().createAndDisplayGUI();
}
});
}
}
class RectangleComponent extends JComponent {
private Color colour;
private static final int MARGIN = 10;
private int width;
private int height;
private int originalWidth;
private RoundRectangle2D roundedRectangle;
public RectangleComponent(Color c, int w, int h) {
colour = c;
width = w;
height = h;
originalWidth = width;
}
/*
* Overriding this method, so that
* the size of the JComponent
* can be determined, on the screen
* or by the LayoutManager concern.
*/
#Override
public Dimension getPreferredSize() {
return (new Dimension(width, height));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
roundedRectangle = new RoundRectangle2D.Float(MARGIN, MARGIN,
width, height, MARGIN, MARGIN);
g2d.setPaint(colour);
g2d.draw(roundedRectangle);
g2d.fill(roundedRectangle);
}
public void subtractLife(int amount) {
width -= amount;
System.out.println("ORIGINAL Width : " + originalWidth);
System.out.println("Width : " + width);
if (width > 0) {
roundedRectangle.setRoundRect(MARGIN, MARGIN, width, height,
MARGIN, MARGIN);
/*
* This repaint() will call the paintComponent(...)
* by itself, so nothing else to be done.
*/
repaint();
} else {
width += amount;
}
}
public void addLife(int amount) {
width += amount;
System.out.println("ORIGINAL Width : " + originalWidth);
System.out.println("Width : " + width);
if (width < originalWidth) {
roundedRectangle.setRoundRect(MARGIN, MARGIN, width, height,
MARGIN, MARGIN);
repaint();
} else {
width -= amount;
}
}
}
Do ask any question, that might can arise as you go through this program :-), I be HAPPY to help on that :-)
**LATEST EDIT WITH TWO COLOURS : **
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.RoundRectangle2D;
import javax.swing.*;
public class CustomPainting {
private RectangleComponent lifeDeath;
private void createAndDisplayGUI() {
JFrame frame = new JFrame("Custom Painting");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
JPanel centerPanel = new JPanel();
centerPanel.setLayout(new GridLayout(0, 2, 5, 5));
// Specifying the WIDTH, HEIGHT and Colour for this JComponent.
lifeDeath = new RectangleComponent(Color.GREEN, Color.RED, 20, 20);
centerPanel.add(lifeDeath);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(1, 2, 5, 5));
JButton incLifeButton = new JButton("INCREASE LIFE");
incLifeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
lifeDeath.addLife(1);
}
});
JButton decLifeButton = new JButton("DECREASE LIFE");
decLifeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
lifeDeath.subtractLife(1);
}
});
buttonPanel.add(incLifeButton);
buttonPanel.add(decLifeButton);
frame.getContentPane().add(centerPanel, BorderLayout.CENTER);
frame.getContentPane().add(buttonPanel, BorderLayout.PAGE_END);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String\u005B\u005D args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new CustomPainting().createAndDisplayGUI();
}
});
}
}
class RectangleComponent extends JComponent {
private Color lifeColour;
private Color deathColour;
private static final int MARGIN = 10;
private int widthLife;
private int widthDeath;
private int height;
private int originalWidth;
private RoundRectangle2D roundedRectangle;
public RectangleComponent(Color lc, Color dc, int w, int h) {
lifeColour = lc;
deathColour = dc;
widthLife = w;
height = h;
originalWidth = widthLife;
widthDeath = 0;
}
/*
* Overriding this method, so that
* the size of the JComponent
* can be determined, on the screen
* or by the LayoutManager concern.
*/
#Override
public Dimension getPreferredSize() {
return (new Dimension(originalWidth, height));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
roundedRectangle = new RoundRectangle2D.Float((MARGIN + widthDeath), MARGIN,
widthLife, height, MARGIN, MARGIN);
g2d.setPaint(lifeColour);
g2d.draw(roundedRectangle);
g2d.fill(roundedRectangle);
roundedRectangle.setRoundRect(MARGIN, MARGIN,
widthDeath, height, MARGIN, MARGIN);
g2d.setPaint(deathColour);
g2d.draw(roundedRectangle);
g2d.fill(roundedRectangle);
}
public void subtractLife(int amount) {
widthLife -= amount;
widthDeath += amount;
System.out.println("ORIGINAL Width : " + originalWidth);
System.out.println("Width Life : " + widthLife);
System.out.println("Width Death : " + widthDeath);
if (widthLife > 0 && widthDeath < originalWidth) {
/*
* This repaint() will call the paintComponent(...)
* by itself, so nothing else to be done.
*/
repaint();
} else {
widthLife += amount;
widthDeath -= amount;
}
}
public void addLife(int amount) {
widthLife += amount;
widthDeath -= amount;
System.out.println("ORIGINAL Width : " + originalWidth);
System.out.println("Width Life : " + widthLife);
System.out.println("Width Death : " + widthDeath);
if (widthLife < originalWidth && widthDeath > 0) {
repaint();
} else {
widthLife -= amount;
widthDeath += amount;
}
}
}

No need to pass JPanel to the constructor of RectangleComponent just to get Graphics, and no need to manually call paintComponent. See Painting in AWT and Swing. Check out this example that demonstrates a custom component that paints a rectangle.

Your code is a bit creative, a bit crazy, and with logic that is very hard to follow. The most unusual aspect is that it has two JFrames, one called "frame", and one the GameFrame object itself, both of which get components added, but only one of which shows. You also have many methods that return void (which if over-used increases code smell) and only add to making the code more confusing.
For example,
public GameFrame(char x) {
// here you set up the "frame" JFrame
frame.setSize(1024, 768);
frame.setTitle("Game");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
FlowLayout layout = new FlowLayout();
createPanels(x);
healthPanel.setLayout(layout);
buttonPanel.setLayout(layout);
mainPanel.setLayout(layout);
// here you add content to the frame JFrame, and pack it
frame.getContentPane().add(mainPanel);
frame.pack();
repaint(); // and then call repaint on the "this" JFrame?
}
public RectangleComponent getLife() {
return life;
}
private void createHealth() {
life = new RectangleComponent(green, healthPanel);
death = new RectangleComponent(red, healthPanel);
}
private void createPanels(char x) {
add(healthPanel); // now you add content to the "this" JFrame
pack(); // and pack it
createBar(x);
createHealth();
mainPanel.add(buttonPanel);
mainPanel.add(healthPanel); // and then re-add a JPanel into a second JPanel?
healthPanel.add(death);
healthPanel.add(life);
buttonPanel.add(bar.getSpell1());
buttonPanel.add(bar.getSpell2());
buttonPanel.add(bar.getSpell3());
add(mainPanel); // and then re -add the mainPanel into the "this" JFrame???
}
This is all very confusing, and not likely going to work.
Then there's your trying to call paintComponent directly and calling getGraphics on a JComponent, both of which should not be done. You will want to go through the graphics tutorials to see how to do this correctly.
I recommend that you consider re-writing this, and first and foremost, using only one JFrame, and organizing your code better.

JPanel repaint issue

I have a JFrame which contains 2 JPanel subclass and 2 JLabel in BorderLayout. One of the JPanel contains JButtons and the other is used for displaying graphics. The JLabels are in north and south, the button JPanel in the west and the display JPanel in center.
The display JPanel requires constant refresh, so i invoke its repaint() method via the action event generated by swing timer. I also override its paintComponent() method to do my drawings.
Instead of displaying what i have drawn, the "content of the JFrame" is being drawn onto the display JPanel. I am aware that i can simply "clear" the display JPanel by using g.fillRect() or super.paintComponent() before doing my drawings.
I am just curious why this happens.
i'm using jdk 1.6u27. below is my code:
package test;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class Main {
public static void main(String[] args) {
Simulation sim = new Simulation();
}
}
class Simulation extends JFrame {
public JLabel state;
private JLabel id;
private ButtonPanel control;
private Display display;
public Simulation() {
id = new JLabel("Test");
state = new JLabel("Test");
control = new ButtonPanel();
display = new Display(this);
this.setLayout(new BorderLayout());
this.add(id, BorderLayout.NORTH);
this.add(control, BorderLayout.WEST);
this.add(display, BorderLayout.CENTER);
this.add(state, BorderLayout.SOUTH);
this.setSize(500, 600);
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public ButtonPanel getControl() {
return this.control;
}
}
class ButtonPanel extends JPanel implements ActionListener {
public JButton b[] = new JButton[8];
public boolean bp[] = new boolean[8];
public ButtonPanel() {
this.setLayout(new GridLayout(8, 1));
for (int i = 0; i < b.length; i++) {
b[i] = new JButton(""+i);
b[i].addActionListener(this);
bp[i] = false;
this.add(b[i]);
}
}
public void actionPerformed(ActionEvent e) {
//do something
}
}
class Display extends JPanel implements ActionListener {
private Timer tm;
private int yco;
private Simulation sim;
public Display(Simulation sim) {
tm = new Timer(100, this);
tm.start();
yco = 0;
this.sim = sim;
}
#Override
public void paintComponent(Graphics g) {
//draw something
g.drawLine(0, yco, 100, 100);
}
public void actionPerformed(ActionEvent e) {
yco ++;
this.repaint();
}
}

Without super.paintComponent(g), the result depends on your platform's default for the opacity property of the JPanel UI delegate, PanelUI. Mine happens to be true, but you can experiment on your platform, as suggested below.
Addendum: "If you do not honor the opaque property you will likely see visual artifacts."—paintComponent(). The artifact you observe will vary by platform, but it is not atypical. In effect, you are breaking the promise to draw every pixel, and you see whatever is left over in some buffer.
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
public class Main {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
Simulation sim = new Simulation();
}
});
}
}
class Simulation extends JFrame {
public JCheckBox state;
private JLabel id;
private ButtonPanel control;
private Display display;
public Simulation() {
id = new JLabel("Test");
state = new JCheckBox("Opaque");
control = new ButtonPanel();
display = new Display(this);
this.setLayout(new BorderLayout());
this.add(id, BorderLayout.NORTH);
this.add(control, BorderLayout.WEST);
this.add(display, BorderLayout.CENTER);
this.add(state, BorderLayout.SOUTH);
state.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent e) {
display.setOpaque(e.getStateChange() == ItemEvent.SELECTED);
}
});
state.setSelected(true);
this.pack();
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public ButtonPanel getControl() {
return this.control;
}
}
class ButtonPanel extends JPanel {
private static final int N = 8;
private List<JToggleButton> list = new ArrayList<JToggleButton>(N);
public ButtonPanel() {
this.setLayout(new GridLayout(0, 1));
for (int i = 0; i < N; i++) {
final JToggleButton b = new JToggleButton(String.valueOf(i));
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//System.out.println(b.isSelected());
}
});
list.add(b);
this.add(b);
}
}
}
class Display extends JPanel {
private Simulation sim;
private Timer tm;
private int yco;
public Display(Simulation sim) {
this.setPreferredSize(new Dimension(320, 320));
this.setOpaque(true);
this.sim = sim;
tm = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
yco++;
repaint();
}
});
tm.start();
}
#Override
public void paintComponent(Graphics g) {
//super.paintComponent(g);
g.drawLine(0, yco, getWidth() / 2, getHeight() / 2);
}
}