We Keep Coding

Can't add JPanel to BorderLayout.CENTER

I am just Starting out with JAVA.
I have say a JPanel x, a JPanel y and a BorderLayout JPanel z.
When I try to change the contents of the center of z from default x t y, it works but it doesn't go back to x. I AM calling revalidate() after each. Help please.
The class below is where the problem is.
Main Class Below
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.LayoutManager;
import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingConstants;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
#SuppressWarnings({ "serial", "unused" })
public class Manager extends JFrame {
private JPanel contentPane;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Manager frame = new Manager();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public Manager() {
setTitle("Popper");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
double width = screenSize.getWidth();
double height = screenSize.getHeight();
height = height/5.1;
setSize((int)width, (int)height);
setExtendedState(getExtendedState() | JFrame.MAXIMIZED_BOTH);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(0,0,0,0));
setContentPane(contentPane);
contentPane.setBackground(new Color(14,99,165));
contentPane.setLayout(new BorderLayout(0, 0));
ImageIcon image = new ImageIcon("D:/popper26.png");
setIconImage(image.getImage());
JPanel pane = new JPanel();
calcu cal = new calcu();
curr nup = new curr();
stopc newst = new stopc();
pane.setLayout(new FlowLayout(FlowLayout.CENTER));
JPanel mainpanel = new JPanel();
BorderLayout x =new BorderLayout(0,0);
mainpanel.setLayout(x);
mainpanel.setBackground(Color.WHITE);
JLabel madeby = new JLabel("Project By Anant Bhasin");
madeby.setHorizontalAlignment(SwingConstants.RIGHT);
mainpanel.add(madeby, BorderLayout.SOUTH);
JPanel logo = new JPanel();
logo.setLayout(new FlowLayout(FlowLayout.CENTER));
JLabel jk = new JLabel(new ImageIcon("D:/popper2.png"));
logo.add(jk, BorderLayout.NORTH);
logo.setBackground(Color.decode("#1abc9c"));
mainpanel.add(logo, BorderLayout.NORTH);
mainpanel.add(cal, BorderLayout.CENTER);
contentPane.add(mainpanel, BorderLayout.CENTER);
JPanel newj = new JPanel();
BoxLayout bxl = new BoxLayout(newj, BoxLayout.PAGE_AXIS);
newj.setLayout(bxl);
newj.setBackground(new Color(58,115,144));
contentPane.add(newj, BorderLayout.WEST);
Border emptyBorder = BorderFactory.createEmptyBorder();
JButton calc = new JButton(new ImageIcon("D:/calc.png"));
newj.add(calc);
calc.setBorder(emptyBorder);
calc.setFocusPainted(false);
calc.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
mainpanel.add(BorderLayout.CENTER, cal);
mainpanel.revalidate();
}
});
JButton currb = new JButton(new ImageIcon("D:/curr.png"));
currb.setBorder(emptyBorder);
newj.add(currb);
currb.setFocusPainted(false);
currb.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
mainpanel.add(BorderLayout.CENTER, nup);
mainpanel.revalidate();
}
});
JButton stop = new JButton(new ImageIcon("D:/stop.png"));
stop.setBorder(emptyBorder);
newj.add(stop);
stop.setFocusPainted(false);
stop.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
mainpanel.add(BorderLayout.CENTER, newst);
mainpanel.revalidate();
}
});
JButton timer = new JButton(new ImageIcon("D:/timer.png"));
timer.setBorder(emptyBorder);
newj.add(timer);
timer.setFocusPainted(false);
JButton memo = new JButton(new ImageIcon("D:/memo.png"));
memo.setBorder(emptyBorder);
newj.add(memo);
memo.setFocusPainted(false);
}
}

A BorderLayout is not designed to display multiple components with the same constraint because of the way ZOrder painting works in Swing.
If you need the ability to swap panels, then you should be using a CardLayout.
A CardLayout lets you specify the name of the panel that you want to display. Read the section from the Swing tutorial on How to Use CardLayout for more information and working examples.
You set up the layout with code like:
JPanel main = new JPanel( new CardLayout() );
main.add(panelx, "X");
main.add(panely, "Y");
Then to swap a panel you use code like:
CardLayout cl = (CardLayout)(main.getLayout());
cl.show(main, "X");

JFrame doesn't conform JPanel's setMinimunSize()

I expect JPanel's setMinimumSize() to confine the resizing of JFrame too, but it doesn't.
The following is my example code:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JSplitPane;
public class AutoResize{
public static void main(String[] args) {
JPanel leftPanel = new JPanel();
JPanel rightPanel = new JPanel();
leftPanel.setBackground(Color.RED);
rightPanel.setBackground(Color.BLUE);
leftPanel.setSize(500,400);
rightPanel.setSize(500,400);
Dimension d = new Dimension(450,300);
leftPanel.setMinimumSize(d);
rightPanel.setMinimumSize(d);
JSplitPane split;
split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, leftPanel, rightPanel);
split.setDividerLocation(400);
JFrame frame = new JFrame();
frame.getContentPane().setLayout(new BorderLayout());
frame.getContentPane().add(split, BorderLayout.CENTER);
frame.setSize(1000, 800);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
If you resize JFrame into a very small size it produces this:
What I want is that JFrame couldn't be resized into a smaller region than JPanels' minimum size. Is there anyway to implement this?

All I need is adding frame.setMinimumSize(); , I feel dumb.
Thanks #Andrew Thompson #MadProgrammer and #user1803551
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Toolkit;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JSplitPane;
public class AutoResize{
private final Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
private final double w = screenSize.getWidth();
private final double h = screenSize.getHeight();
private final Dimension d = new Dimension((int) w/3,(int) h/3);
public void run() {
JPanel leftPanel = new JPanel();
JPanel rightPanel = new JPanel();
leftPanel.setBackground(Color.RED);
rightPanel.setBackground(Color.BLUE);
//leftPanel.setSize(500,400);
//rightPanel.setSize(500,400);
leftPanel.setMinimumSize(d);
rightPanel.setMinimumSize(d);
JSplitPane split;
split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, leftPanel, rightPanel);
split.setDividerLocation(400);
JFrame frame = new JFrame();
frame.getContentPane().setLayout(new BorderLayout());
frame.getContentPane().add(split, BorderLayout.CENTER);
frame.setSize((int) w,(int) h);
//frame.pack();
frame.setMinimumSize(new Dimension((int) w/3*2,(int) h/3*2));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public static void main(String[] args) {
AutoResize test = new AutoResize();
test.run();
}
}

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);

JScrollPane with JPanel nothing see

I wnat add to JFrame JSrollPane. ScrollPane contains a JPanels. But I have problem when I add first JPanel to ScrollPane i see nothing when I add JPanel to JFrame I see JPanels. So where I make mistake? Here code:
import java.awt.Color;
import java.awt.Dimension;
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.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollBar;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
public class AddingJPanels {
public static void main(String... args) {
JFrame jF = new JFrame();
PanelMain pM = new PanelMain();
Panel p = new Panel("sas");
JPanel jp = makeJPanel(10);
p.setPreferredSize(new Dimension(600,600));
JScrollPane scroll = new JScrollPane();
scroll.add(jp);
JScrollBar verticalPane = scroll.getVerticalScrollBar();
verticalPane.setValue(verticalPane.getMinimum());
verticalPane.setValue(20);
//scroll.setPreferredSize(new Dimension(570, 300));
scroll.setPreferredSize(new Dimension(400,500));
pM.add(scroll);
//JTabbedPane tB = new JTabbedPane();
//tB.addTab(":]", null, pM, "Tab 3");
jF.add(jp);
jF.setSize(new Dimension(500,500));
jF.setVisible(true);
}
static JPanel makeJPanel(int i){
JPanel jPl = new JPanel();
jPl.setLayout(new GridLayout(i,0));
JLabel lebel;
for(int j=0;j<i;++j){
JPanel p = new JPanel();
p.setLayout(new GridLayout(2,2));
JButton b = new JButton("asa");
p.add(b);
p.setBorder(BorderFactory.createLineBorder(Color.black));
p.setPreferredSize(new Dimension(400,400));
lebel = new JLabel("Napis: "+j);
p.add(lebel);
JTextField jTF = new JTextField("Nic",20);
p.add(jTF);
jPl.add(p);
}
return jPl;
}
}
class Frame extends JFrame {
public Frame() {
super("Frame");
this.setPreferredSize(new Dimension(200, 200));
}
public void see() {
this.setVisible(true);
}
}
class PanelMain extends JPanel {
JButton b = new JButton("press me");
public PanelMain() {
this.add(b);
b.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
System.out.println("Pressed");
}
});
}
}
class Panel extends JPanel {
JLabel l;
public Panel(String s) {
l = new JLabel(s);
this.add(l);
}
}
When I make jF.add(scroll) is no effect.

add() doesn't work on a JScrollPane. You need to use setViewport() or else pass a component in the contstructor.
JScrollPane scroll = new JScrollPane(jp);
or
JScrollPane scroll = new JScrollPane();
scroll.setViewport(jp);

JScrollPane scroll = new JScrollPane(jp);

use:
scroll.setViewportView(jp);

Centering image in a JFrame?

I'm creating an about JFrame for my program. I have an icon which I used for the program and I have that show up as the first thing on the about JFrame, but I'm having issues trying to center the image. If I do some kind of centering it screws up the whole alignment of everything else.
I'm trying to have all the JLabels, other than the icon, to be left aligned. Then have the icon aligned to the center.
I had to remove some personal information, whatever I did remove I put them between "[]".
import java.awt.Dimension;
import java.awt.Font;
import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class About extends JFrame {
public About() {
super("About [PROGRAM]");
setIconImage([PROGRAM].getInstance().setIcon());
JPanel main = new JPanel();
main.setLayout(new BoxLayout(main, BoxLayout.Y_AXIS));
main.setBorder(BorderFactory.createEmptyBorder(10,10,10,10));
JLabel icon = new JLabel("", new ImageIcon(getClass().getResource(Constants.ICON_FULL)), JLabel.CENTER);
JLabel name = new JLabel("[PROGRAM]");
JLabel expandedName = new JLabel("[PROGRAM DESCRIPTION]");
JLabel copyright = new JLabel("[COPYRIGHT JUNK]");
JLabel credits = new JLabel("[CREDITS]");
name.setFont(new Font(name.getFont().getFamily(), Font.BOLD, 18));
copyright.setBorder(BorderFactory.createEmptyBorder(0,0,10,0));
main.add(icon);
main.add(Box.createRigidArea(new Dimension(0, 10)));
main.add(name);
main.add(expandedName);
main.add(copyright);
main.add(credits);
add(main);
pack();
setLocationRelativeTo(null);
setVisible(true);
}
}

Consider using some layouts to help you out. Ones that come to mind include BorderLayout with the icon in the BorderLayout.CENTER position. You can stack stuff on one side using a BoxLayout using JPanel that is added to the main BorderLayout-using JPanel.
e.g.,
import java.awt.BorderLayout;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;
#SuppressWarnings("serial")
public class About extends JDialog {
public static final String IMAGE_PATH = "http://upload.wikimedia.org/wikipedia/"
+ "commons/thumb/3/39/European_Common_Frog_Rana_temporaria.jpg/"
+ "800px-European_Common_Frog_Rana_temporaria.jpg";
public About(JFrame frame) {
super(frame, "About [PROGRAM]", true);
ImageIcon myIcon = null;
try {
URL imgUrl = new URL(IMAGE_PATH);
BufferedImage img = ImageIO.read(imgUrl);
myIcon = new ImageIcon(img);
} catch (MalformedURLException e) {
e.printStackTrace();
System.exit(-1);
} catch (IOException e) {
e.printStackTrace();
System.exit(-1);
}
JPanel main = new JPanel(new BorderLayout());
main.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
JLabel centerLabel = new JLabel(myIcon);
JLabel name = new JLabel("[PROGRAM]");
JLabel expandedName = new JLabel("[PROGRAM DESCRIPTION]");
JLabel copyright = new JLabel("[COPYRIGHT JUNK]");
JLabel credits = new JLabel("[CREDITS]");
name.setFont(new Font(name.getFont().getFamily(), Font.BOLD, 18));
copyright.setBorder(BorderFactory.createEmptyBorder(0, 0, 10, 0));
int eb = 20;
centerLabel.setBorder(BorderFactory.createEmptyBorder(eb, eb, eb, eb));
JPanel leftPanel = new JPanel();
leftPanel.setLayout(new BoxLayout(leftPanel, BoxLayout.PAGE_AXIS));
leftPanel.add(name);
leftPanel.add(Box.createVerticalGlue());
leftPanel.add(expandedName);
leftPanel.add(copyright);
leftPanel.add(credits);
leftPanel.add(Box.createVerticalGlue());
main.add(centerLabel, BorderLayout.CENTER);
main.add(leftPanel, BorderLayout.LINE_START);
add(main);
pack();
}
public static void main(String[] args) {
final JFrame frame = new JFrame("GUI");
JPanel panel = new JPanel();
panel.add(new JButton(new AbstractAction("About") {
#Override
public void actionPerformed(ActionEvent e) {
About about = new About(frame);
about.setLocationRelativeTo(frame);
about.setVisible(true);
}
}));
frame.add(panel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}