Develop Reference

Why does my Canvas not draw the rectangles

I know this problem has probably already been solved before but I don't really know how to describe the problem well, so I have a hard time finding it.
The problem I have is that I have a canvas that is attached to a panel and that panel is attached to a main panel and that to the frame. When I run the code the canvas does nothing. However if I dont add the button panel it works.
this is my code:
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class ColorFrame extends JFrame {
private static final int FRAMEWIDTH = 400;
private static final int FRAMEHEIGHT = 400;
private int aORec = 4;
private Canvas canvas;
private JPanel mainPanel;
private JPanel panel;
private JPanel buttonPanel;
private JButton lessButton;
private JButton moreButton;
public ColorFrame() {
mainPanel = new JPanel();
panel = new JPanel();
canvas = new painter();
panel.add(canvas);
mainPanel.add(panel, BorderLayout.CENTER);
createComponents();
add(mainPanel);
setSize(FRAMEWIDTH,FRAMEHEIGHT);
setDefaultCloseOperation(3);
}
private void createComponents() {
buttonPanel = new JPanel();
lessButton = new JButton("Less");
moreButton = new JButton("More");
ActionListener bL = new ButtonListener();
lessButton.addActionListener(bL);
moreButton.addActionListener(bL);
buttonPanel.add(moreButton);
buttonPanel.add(lessButton);
mainPanel.add(buttonPanel, BorderLayout.NORTH);
}
class painter extends Canvas {
#Override
public void paint(Graphics g) {
for (int i = 0; i < aORec; i++) {
int tempWidth = (int)(Math.random() * (FRAMEWIDTH-0));
int tempHeight = (int)(Math.random() * (FRAMEHEIGHT -0));
g.drawRect(tempWidth,tempHeight,20,20);
}
}
}
class ButtonListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == moreButton) {
aORec =+ aORec;
canvas.repaint();
} else {
if (aORec != 1) {
aORec -= (aORec*0.5);
canvas.repaint();
} else {
System.out.println("There are not enough rectangles to be drawn.");
}
}
}
}
}

Main panel is created by
mainPanel = new JPanel();
Components are being added to the main panel as
mainPanel.add(panel, BorderLayout.CENTER);
mainPanel.add(buttonPanel, BorderLayout.NORTH);
but no LayoutManager was set, so the default FlowLayout is used, not BorderLayout. Create the panel by
mainPanel = new JPanel(new BorderLayout());
or add the statement
mainPanel.setLayout(new BorderLayout());
This is also valid for panel (otherwise it will not be resized, that is, stay with size zero)
(BorderLayout is the default for JFrame(

How to align JButtons using 2 JPanel objects to form a basic java GUI

I'm attempting to re-create the following, extremely basic GUI seen here:
My output is as follows:
I'm having a difficult time formatting the JButtons. For one thing, no matter what I do I cannot get the second Panel, the 'shapePane' to display below the first Panel the 'colorPane' secondly, I am unable to correctly make the y axis of the buttons larger to give them a fatter appearance. Further, the top panel the 'shapePane' seems to dynamically move as the window is resized whereas, the second 'colorPane' stays in a fixed position regardless of the window resizing.
If someone could please provide a bit of assistance I would be immensely grateful
my code thus far is as follows:
import java.util.*;
import javax.swing.*;
import javax.swing.border.*;
import java.awt.*;
import java.awt.event.*;
public class GUI extends JFrame implements ActionListener, WindowListener
{
private JButton circleButton;
private JButton rectangleButton;
private JButton redButton;
private JButton greenButton;
private JButton blueButton;
private JButton exitButton;
private JTextField textField1;
private JLabel label1;
private JPanel contentPane;
private JPanel colorPane;
private JPanel shapePane;
private JFrame contentFrame;
private int count;
public GUI (String title)
{
super(title);
//setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//setBounds(100, 100, 945, 580);
//contentFrame = new JFrame();
//contentPane = new JPanel();
//contentFrame.add(contentPane);
//contentPane.setBorder(new LineBorder(new Color(50, 5, 232), 4, true));
//setContentPane(contentPane);
//contentPane.setLayout(null);
colorPane = new JPanel();
//colorPane.setBorder(new LineBorder(new Color(34, 174, 82), 1, true));
colorPane.setBounds(10, 32, 515, 125);
//contentPane.add(colorPane);
//colorPane.setLayout(null);
shapePane = new JPanel();
shapePane.setBounds(10, 165, 515, 315);
//shapePane.setBorder(new LineBorder(new Color(34, 174, 82), 1, true));
//contentPane.add(shapePane);
//shapePane.setLayout(null);
circleButton = new JButton("Circle");
circleButton.setHorizontalAlignment(SwingConstants.LEFT);
rectangleButton = new JButton("Rectangle");
rectangleButton.setHorizontalAlignment(SwingConstants.LEFT);
greenButton = new JButton("Green");
redButton = new JButton("Red");
blueButton = new JButton("Blue");
exitButton = new JButton("Exit");
textField1 = new JTextField(20);
label1 = new JLabel("current time here");
colorPane.add(redButton, BorderLayout.CENTER);
colorPane.add(greenButton, BorderLayout.CENTER);
colorPane.add(blueButton, BorderLayout.CENTER);
shapePane.add(rectangleButton, BorderLayout.SOUTH);
shapePane.add(circleButton, BorderLayout.SOUTH);
shapePane.add(exitButton, BorderLayout.SOUTH);
getContentPane().add(textField1, BorderLayout.EAST);
getContentPane().add(label1, BorderLayout.WEST);
getContentPane().add(colorPane, BorderLayout.CENTER);
//contentFrame.add(colorPane);
getContentPane().add(shapePane, BorderLayout.CENTER);
//contentFrame.add(shapePane);
}
#Override
public void windowOpened(WindowEvent e) {
// TODO Auto-generated method stub
}
#Override
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
#Override
public void windowClosed(WindowEvent e) {
// TODO Auto-generated method stub
}
#Override
public void windowIconified(WindowEvent e) {
// TODO Auto-generated method stub
}
#Override
public void windowDeiconified(WindowEvent e) {
// TODO Auto-generated method stub
}
#Override
public void windowActivated(WindowEvent e) {
// TODO Auto-generated method stub
}
#Override
public void windowDeactivated(WindowEvent e) {
// TODO Auto-generated method stub
}
#Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
}
}

The following should get you started:
Set label's vertical and horizontal position so it appears in the bottom left
and and its desired width. For more layout flexibility consider warping it in a JPanel:
label1 = new JLabel("current time here");
label1.setVerticalAlignment(SwingConstants.BOTTOM);
label1.setHorizontalAlignment(SwingConstants.LEFT);
label1.setPreferredSize(new Dimension(200, 0)); //height is set by the layout manger
getContentPane().add(label1, BorderLayout.WEST);
Use a GridLayout for the buttons pane:
colorPane = new JPanel();
colorPane.setLayout(new GridLayout(2, 3));
Initialize buttons and add them one by one to the grid pane:
redButton = makeButton("Red");
colorPane.add(redButton);
Where makeButton is a method implemented to avoid duplicating code:
private JButton makeButton(String text) {
JButton b = new JButton(text);
b.setHorizontalAlignment(SwingConstants.LEFT);
b.addActionListener(this);
b.setPreferredSize(new Dimension(125, 55)); //set preferred and let Layout manager do its work
return b;
}
Set the text area number of columns. Its height is set by the layout manger:
textArea = new JTextArea(0,20);
getContentPane().add(textArea, BorderLayout.EAST);
Putting it all together:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.SwingConstants;
public class GUI extends JFrame implements ActionListener
{
private final JButton circleButton, rectangleButton, redButton;
private final JButton greenButton, blueButton, exitButton;
private final JTextArea textArea;
private final JLabel label1;
private final JPanel colorPane;
private static final int ROWS = 2, COLS = 3;
public GUI (String title)
{
super(title);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//set label's vertical and horizontal position so it appears in the bottom left
//and and its desired width
//for more layout flexibility consider warping it in a JFrame
label1 = new JLabel("current time here");
label1.setVerticalAlignment(SwingConstants.BOTTOM);
label1.setHorizontalAlignment(SwingConstants.LEFT);
label1.setPreferredSize(new Dimension(200, 0)); //height is set by the layout manger
getContentPane().add(label1, BorderLayout.WEST);
//use a GridLayout for the buttons pane
colorPane = new JPanel();
colorPane.setLayout(new GridLayout(ROWS, COLS));
getContentPane().add(colorPane, BorderLayout.CENTER);//each BorderLayout position can hold ONE component
redButton = makeButton("Red");
colorPane.add(redButton);
greenButton = makeButton("Green");
colorPane.add(greenButton);
blueButton = makeButton("Blue");
colorPane.add(blueButton);
rectangleButton = makeButton("Rectangle");
colorPane.add(rectangleButton);
circleButton = makeButton("Circle");
colorPane.add(circleButton);
exitButton = makeButton("Exit");
colorPane.add(exitButton);
//set the text area number of columns. Its height is set by the layout manger
textArea = new JTextArea(0,20);
getContentPane().add(textArea, BorderLayout.EAST);
pack();
}
private JButton makeButton(String text) {
JButton b = new JButton(text);
b.setHorizontalAlignment(SwingConstants.LEFT);
b.addActionListener(this);
b.setPreferredSize(new Dimension(125, 55)); //set preferred and let Layout manager do its work
return b;
}
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(((JButton)e.getSource()).getText()+ " button pressed");
}
public static void main(String[] args) {
new GUI("My Gui").setVisible(true);
}
}
A simple enhancement could be storing all button references in a Map:
public class GUI extends JFrame implements ActionListener
{
private Map <String, JButton> buttons; // a map to hold references to all buttons
private final JTextArea textArea;
private final JLabel label1;
private final JPanel colorPane;
private static final int ROWS = 2, COLS = 3;
private static final String[] BUTTON_LABELS = {"Red","Green", "Blue", "Rectangle", "Circle", "Exit"};
public GUI (String title)
{
super(title);
buttons = new HashMap<>();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//set label's vertical and horizontal position so it appears in the bottom left
//and and its desired width
//for more layout flexibility consider warping it in a JFrame
label1 = new JLabel("current time here");
label1.setVerticalAlignment(SwingConstants.BOTTOM);
label1.setHorizontalAlignment(SwingConstants.LEFT);
label1.setPreferredSize(new Dimension(200, 0)); //height is set by the layout manger
getContentPane().add(label1, BorderLayout.WEST);
//use a GridLayout for the buttons pane
colorPane = new JPanel();
colorPane.setLayout(new GridLayout(ROWS, COLS));
getContentPane().add(colorPane, BorderLayout.CENTER);//each BorderLayout position can hold ONE component
for(String text : BUTTON_LABELS){
JButton button = makeButton(text);
colorPane.add(button);
buttons.put(text, button);
}
//set the text area number of columns. Its height is set by the layout manger
textArea = new JTextArea(0,20);
getContentPane().add(textArea, BorderLayout.EAST);
pack();
}
private JButton makeButton(String text) {
JButton b = new JButton(text);
b.setHorizontalAlignment(SwingConstants.LEFT);
b.addActionListener(this);
b.setPreferredSize(new Dimension(125, 55)); //set preferred and let Layout manager do its work
return b;
}
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(((JButton)e.getSource()).getText()+ " button pressed");
}
public static void main(String[] args) {
new GUI("My Gui").setVisible(true);
}
}

How to get the TitledBorder's title to display properly in the GUI

I have the GUI displaying properly for the most part, except for one thing. The TitledBorder("Numeric Type") does not display the entire title for the right JPanel. I believe it has something to do with the BorderLayout Manager. Instead of displaying "Numeric Type" within the border, just "Numeric..." displays. Any help will be greatly appreciated.
public class P3GUI extends JFrame {
private JLabel originalList;
private JTextField originalSort;
private JLabel sortedList;
private JTextField newSort;
private JPanel panel;
private JButton performSort;
private JRadioButton ascending;
private JRadioButton descending;
private ButtonGroup sort;
private JRadioButton integer;
private JRadioButton fraction;
private ButtonGroup numType;
private JPanel inputPanel, outputPanel, calculatePanel, radioPanel;
private JPanel left, right;
public P3GUI () {
super("Binary Search Tree Sort");
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
originalList = new JLabel("Original List");
originalSort = new JTextField(20);
inputPanel = new JPanel();
inputPanel.add(originalList);
inputPanel.add(originalSort);
sortedList = new JLabel("Sorted List");
newSort = new JTextField(20);
newSort.setEditable(false);
outputPanel = new JPanel();
outputPanel.add(sortedList);
outputPanel.add(newSort);
panel = new JPanel();
panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
panel.add(inputPanel);
panel.add(outputPanel);
add(panel, BorderLayout.NORTH);
performSort = new JButton("Perform Sort");
calculatePanel = new JPanel();
calculatePanel.add(performSort);
add(calculatePanel, BorderLayout.CENTER);
ascending = new JRadioButton("Ascending");
descending = new JRadioButton("Descending");
sort = new ButtonGroup();
sort.add(ascending);
sort.add(descending);
integer = new JRadioButton("Integer");
fraction = new JRadioButton("Fraction");
numType = new ButtonGroup();
numType.add(integer);
numType.add(fraction);
radioPanel = new JPanel();
radioPanel.setLayout(new FlowLayout());
left = new JPanel();
left.setLayout(new GridLayout(2,1));
left.setBorder(BorderFactory.createTitledBorder("Sort Order"));
left.add(ascending);
left.add(descending);
right = new JPanel();
right.setLayout(new GridLayout(2,1));
right.setBorder(BorderFactory.createTitledBorder("Numeric Type"));
right.add(integer);
right.add(fraction);
radioPanel.add(left);
radioPanel.add(right);
add(radioPanel, BorderLayout.SOUTH);
pack();
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
new P3GUI().setVisible(true);
}
});
}
}

The problem is that the right JPanel is too small to display the entire title, and so it gets truncated. I'd suggest placing the bottom two JPanels into another that uses GridLayout, and then place them in such a way that they expand to fit the bottom of your GUI. When spread out, the title has a much greater chance of being fully displayed (but not a guarantee, mind you!).
For example, if you make the main GUI use a BorderLayout, and add this GridLayout using JPanel into the BorderLayout.CENTER position, it will fill it completely. Then the top components, the TextFields and JButton can be added to another JPanel, say one that uses a GridBagLayout, and add that to the main JPanel's BorderLayout.PAGE_START position.
For example, the following code produces this GUI:
import java.awt.BorderLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Insets;
import java.awt.event.KeyEvent;
import javax.swing.*;
#SuppressWarnings("serial")
public class P3GUI2 extends JPanel {
private static final int COLS = 20;
private JTextField originalSort = new JTextField(COLS);
private JTextField newSort = new JTextField(COLS);
private JButton performSort = new JButton("Perform Sort");
private JRadioButton ascending = new JRadioButton("Ascending");
private JRadioButton descending = new JRadioButton("Descending");
private ButtonGroup sort = new ButtonGroup();
private JRadioButton integer = new JRadioButton("Integer");
private JRadioButton fraction = new JRadioButton("Fraction");
private ButtonGroup numType = new ButtonGroup();
public P3GUI2() {
JPanel topPanel = new JPanel(new GridBagLayout());
topPanel.add(new JLabel("Original List:"), createGbc(0, 0));
topPanel.add(originalSort, createGbc(1, 0));
topPanel.add(new JLabel("Sorted List:"), createGbc(0, 1));
topPanel.add(newSort, createGbc(1, 1));
performSort.setMnemonic(KeyEvent.VK_P);
JPanel btnPanel = new JPanel();
btnPanel.add(performSort);
JPanel sortOrderPanel = createTitlePanel("Sort Order");
JPanel numericPanel = createTitlePanel("Numeric Type");
sortOrderPanel.add(ascending);
sortOrderPanel.add(descending);
sort.add(ascending);
sort.add(descending);
numericPanel.add(integer);
numericPanel.add(fraction);
numType.add(integer);
numType.add(fraction);
JPanel radioPanels = new JPanel(new GridLayout(1, 0, 3, 3));
radioPanels.add(sortOrderPanel);
radioPanels.add(numericPanel);
setBorder(BorderFactory.createEmptyBorder(3, 3, 3, 3));
setLayout(new BorderLayout(3, 3));
add(topPanel, BorderLayout.PAGE_START);
add(btnPanel, BorderLayout.CENTER);
add(radioPanels, BorderLayout.PAGE_END);
}
private JPanel createTitlePanel(String title) {
JPanel panel = new JPanel(new GridLayout(0, 1, 3, 3));
panel.setBorder(BorderFactory.createTitledBorder(title));
return panel;
}
private GridBagConstraints createGbc(int x, int y) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.anchor = x == 0 ? GridBagConstraints.WEST : GridBagConstraints.EAST;
gbc.insets = new Insets(3, 3, 3, 3);
gbc.weightx = 1.0;
gbc.weighty = 1.0;
return gbc;
}
private static void createAndShowGui() {
P3GUI2 mainPanel = new P3GUI2();
JFrame frame = new JFrame("Binary Search Tree Sort");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
Or you could place the above btnPanel into the main one BorderLayout.CENTER and then place the radioPanels into the main one BorderLayout.PAGE_END. This will display a GUI of the same appearance but it will expand differently if re-sized.

The preferred size of the panel (as determined by the layout manager) does not consider the size of the text in the TitledBorder so the title can get truncated.
Here is a custom JPanel that can be used with a TitleBorder. The getPreferredSize() method has been customized to use the maximum width of:
the default getPreferredSize() calculation
the width of the text in the TitledBorder
Here is a simple example:
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
public class TitledBorderPanel extends JPanel
{
/**
** The preferred width on the panel must consider the width of the text
** used on the TitledBorder
*/
#Override
public Dimension getPreferredSize()
{
Dimension preferredSize = super.getPreferredSize();
Border border = getBorder();
int borderWidth = 0;
if (border instanceof TitledBorder)
{
Insets insets = getInsets();
TitledBorder titledBorder = (TitledBorder)border;
borderWidth = titledBorder.getMinimumSize(this).width + insets.left + insets.right;
}
int preferredWidth = Math.max(preferredSize.width, borderWidth);
return new Dimension(preferredWidth, preferredSize.height);
}
private static void createAndShowGUI()
{
JPanel panel = new TitledBorderPanel();
panel.setBorder( BorderFactory.createTitledBorder("File Options Command List:") );
panel.setLayout( new BoxLayout(panel, BoxLayout.Y_AXIS) );
panel.add( new JLabel("Open") );
panel.add( new JLabel("Close") );
// panel.add( new JLabel("A really wierd file option longer than border title") );
JFrame frame = new JFrame("TitledBorderPanel");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( panel );
frame.setLocationByPlatform( true );
frame.pack();
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater( () -> createAndShowGUI() );
/*
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowGUI();
}
});
*/
}
}

JButton with image background and text alignment

I've got (again) a problem: i got a jbutton with an image on background, but when i want to put some text on it, it will apears on the right side of background, not in button, but aside...
Here is working code, you must only link some image :)
package program;
import java.awt.Image;
import java.awt.Insets;
import java.io.File;
import java.io.IOException;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingConstants;
public class Program {
private static JFrame frame;
private static JPanel panel;
private static JButton button;
private static Image buttonImage;
private static ImageIcon buttonIcon;
public static void main(String[] args) {
frame = new JFrame("Program");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel = new JPanel();
frame.add(panel);
frame.pack();
frame.setVisible(true);
frame.setSize(200,100);
frame.setLocationRelativeTo(null);
frame.setResizable(false);
String imgUrl = "images/";
try {
buttonImage = ImageIO.read(new File(imgUrl+"img.png"));
} catch (IOException e) {
Logger.getLogger(Program.class.getName()).log(Level.SEVERE, null, e);
}
buttonIcon = new ImageIcon(buttonImage);
button = new JButton("TEST", buttonIcon);
panel.add(button);
button.setMargin(new Insets(0, 0, 0, 0));
button.setBounds(0, 0, 146, 67);
button.setOpaque(false);
button.setContentAreaFilled(false);
button.setBorderPainted(false);
}
}

Here are 4 ways to display text on an image:
import java.awt.*;
import javax.swing.*;
import javax.swing.text.*;
public class LabelImageText extends JPanel
{
public LabelImageText()
{
JLabel label1 = new JLabel( new ColorIcon(Color.ORANGE, 100, 100) );
label1.setText( "Easy Way" );
label1.setHorizontalTextPosition(JLabel.CENTER);
label1.setVerticalTextPosition(JLabel.CENTER);
add( label1 );
//
JLabel label2 = new JLabel( new ColorIcon(Color.YELLOW, 200, 150) );
label2.setLayout( new BoxLayout(label2, BoxLayout.Y_AXIS) );
add( label2 );
JLabel text = new JLabel( "More Control" );
text.setAlignmentX(JLabel.CENTER_ALIGNMENT);
label2.add( Box.createVerticalGlue() );
label2.add( text );
label2.add( Box.createVerticalStrut(10) );
//
JLabel label3 = new JLabel( new ColorIcon(Color.GREEN, 200, 150) );
label3.setLayout( new GridBagLayout() );
add( label3 );
JLabel text3 = new JLabel();
text3.setText("<html><center>Text<br>over<br>Image<center></html>");
text3.setLocation(20, 20);
text3.setSize(text3.getPreferredSize());
label3.add( text3 );
//
JLabel label4 = new JLabel( new ColorIcon(Color.CYAN, 200, 150) );
add( label4 );
JTextPane textPane = new JTextPane();
textPane.setText("Add some text that will wrap at your preferred width");
textPane.setEditable( false );
textPane.setOpaque(false);
SimpleAttributeSet center = new SimpleAttributeSet();
StyleConstants.setAlignment(center, StyleConstants.ALIGN_CENTER);
StyledDocument doc = textPane.getStyledDocument();
doc.setParagraphAttributes(0, doc.getLength(), center, false);
textPane.setBounds(20, 20, 75, 100);
label4.add( textPane );
}
public static class ColorIcon implements Icon
{
private Color color;
private int width;
private int height;
public ColorIcon(Color color, int width, int height)
{
this.color = color;
this.width = width;
this.height = height;
}
public int getIconWidth()
{
return width;
}
public int getIconHeight()
{
return height;
}
public void paintIcon(Component c, Graphics g, int x, int y)
{
g.setColor(color);
g.fillRect(x, y, width, height);
}
}
private static void createAndShowUI()
{
JFrame frame = new JFrame("LabelImageText");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( new LabelImageText() );
frame.pack();
frame.setLocationRelativeTo( null );
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowUI();
}
});
}
}

you never set the background,you'v set the icon of the button

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class StringTest extends JFrame
implements ActionListener
{
private JTextField input, result;
private int i;
public StringTest()
{
super("String test");
i=0;
Box box1 = Box.createVerticalBox();
box1.add(new JLabel(" Input:"));
box1.add(Box.createVerticalStrut(10));
box1.add(new JLabel("Result:"));
input = new JTextField(40);
input.setBackground(Color.WHITE);
input.addActionListener(this);
input.selectAll();
result = new JTextField(40);
result.setBackground(Color.YELLOW);
result.setEditable(false);
Box box2 = Box.createVerticalBox();
box2.add(input);
box2.add(Box.createVerticalStrut(10));
box2.add(result);
Box box3 = Box.createHorizontalBox();
box3.add(box1);
box3.add(box2);
Box box4 = Box.createVerticalBox();
JButton new_game = new JButton("NEW GAME");
JLabel game_title =new JLabel("***Welcome to Hangman Game***");
box4.add(game_title);
box4.add(box3);
box4.add(Box.createVerticalStrut(10));
box4.add(box3);
box4.add(Box.createVerticalStrut(10));
box4.add(new_game);
new_game.setAlignmentX(Component.CENTER_ALIGNMENT);
Container c = getContentPane();
c.setLayout(new FlowLayout());
c.add(box4);
//c.add(box2);
// c.add(ok_button);c.add(ok1_button);
input.requestFocus();
}
public void actionPerformed(ActionEvent e)
{
String str = input.getText();
result.setText(str);
if (i%2==0)
result.setBackground(Color.WHITE);
else
result.setBackground(Color.YELLOW);
input.selectAll();
}
public static void main(String[] args)
{
StringTest window = new StringTest();
window.setBounds(100, 100, 600, 100);
window.setDefaultCloseOperation(EXIT_ON_CLOSE);
window.setVisible(true);
}
}

Providing white space in a Swing GUI

A GUI with no white space appears 'crowded'. How can I provide white space without resorting to explicitly setting the position or size of components?­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

Using various LayoutManagers one can provide spacing between various components.
1.) BorderLayout :
Overloaded Constructor : BorderLayout(int horizontalGap, int verticalGap)
Getter and setter methods
For Horizontal Spacing : BorderLayout.getHgap() and BorderLayout.setHgap(int hgap)
For Vertical Spacing : BorderLayout.getVgap() and BorderLayout.setVgap()
2.) FlowLayout :
Overloaded Constructor : FlowLayout(int align, int hgap, int vgap)
Getter and setter methods
For Horizontal Spacing : FlowLayout.getHgap() and FlowLayout.setHgap(int hgap)
For Vertical Spacing : FlowLayout.getVgap() and FlowLayout.setVgap()
3.) GridLayout :
Overloaded Constructor : GridLayout(int rows, int columns, int hgap, int vgap)
Getter and setter methods
For Horizontal Spacing : GridLayout.getHgap() and GridLayout.setHgap(int hgap)
For Vertical Spacing : GridLayout.getVgap() and GridLayout.setVgap()
4.) GridBagLayout :
GridBagConstraints.insets
5.) CardLayout (example) :
CardLayout(int hGap, int vGap)
Example to display all constructors in action :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class LayoutExample {
private final int hGap = 5;
private final int vGap = 5;
private String[] borderConstraints = {
BorderLayout.PAGE_START,
BorderLayout.LINE_START,
BorderLayout.CENTER,
BorderLayout.LINE_END,
BorderLayout.PAGE_END
};
private JButton[] buttons;
private GridBagConstraints gbc;
private JPanel borderPanel;
private JPanel flowPanel;
private JPanel gridPanel;
private JPanel gridBagPanel;
private JPanel cardPanel;
public LayoutExample() {
buttons = new JButton[16];
gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.FIRST_LINE_START;
gbc.insets = new Insets(hGap, vGap, hGap, vGap);
}
private void displayGUI() {
JFrame frame = new JFrame("Layout Example");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
JPanel contentPane = new JPanel(
new GridLayout(0, 1, hGap, vGap));
contentPane.setBorder(
BorderFactory.createEmptyBorder(hGap, vGap, hGap, vGap));
borderPanel = new JPanel(new BorderLayout(hGap, vGap));
borderPanel.setBorder(
BorderFactory.createTitledBorder("BorderLayout"));
borderPanel.setOpaque(true);
borderPanel.setBackground(Color.WHITE);
for (int i = 0; i < 5; i++) {
buttons[i] = new JButton(borderConstraints[i]);
borderPanel.add(buttons[i], borderConstraints[i]);
}
contentPane.add(borderPanel);
flowPanel = new JPanel(new FlowLayout(
FlowLayout.CENTER, hGap, vGap));
flowPanel.setBorder(
BorderFactory.createTitledBorder("FlowLayout"));
flowPanel.setOpaque(true);
flowPanel.setBackground(Color.WHITE);
for (int i = 5; i < 8; i++) {
buttons[i] = new JButton(Integer.toString(i));
flowPanel.add(buttons[i]);
}
contentPane.add(flowPanel);
gridPanel = new JPanel(new GridLayout(2, 2, hGap, vGap));
gridPanel.setBorder(
BorderFactory.createTitledBorder("GridLayout"));
gridPanel.setOpaque(true);
gridPanel.setBackground(Color.WHITE);
for (int i = 8; i < 12; i++) {
buttons[i] = new JButton(Integer.toString(i));
gridPanel.add(buttons[i]);
}
contentPane.add(gridPanel);
gridBagPanel = new JPanel(new GridBagLayout());
gridBagPanel.setBorder(
BorderFactory.createTitledBorder("GridBagLayout"));
gridBagPanel.setOpaque(true);
gridBagPanel.setBackground(Color.WHITE);
buttons[12] = new JButton(Integer.toString(12));
addComp(gridBagPanel, buttons[12], 0, 0, 1, 1
, GridBagConstraints.BOTH, 0.33, 0.5);
buttons[13] = new JButton(Integer.toString(13));
addComp(gridBagPanel, buttons[13], 1, 0, 1, 1
, GridBagConstraints.BOTH, 0.33, 0.5);
buttons[14] = new JButton(Integer.toString(14));
addComp(gridBagPanel, buttons[14], 0, 1, 2, 1
, GridBagConstraints.BOTH, 0.66, 0.5);
buttons[15] = new JButton(Integer.toString(15));
addComp(gridBagPanel, buttons[15], 2, 0, 1, 2
, GridBagConstraints.BOTH, 0.33, 1.0);
contentPane.add(gridBagPanel);
cardPanel = new JPanel(new CardLayout(hGap, vGap));
cardPanel.setBorder(
BorderFactory.createTitledBorder("CardLayout"));
cardPanel.setOpaque(true);
cardPanel.setBackground(Color.WHITE);
cardPanel.add(getPanel(Color.BLUE));
cardPanel.add(getPanel(Color.GREEN));
contentPane.add(cardPanel);
frame.setContentPane(contentPane);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
private JPanel getPanel(Color bColor) {
JPanel panel = new JPanel(new FlowLayout(
FlowLayout.CENTER, hGap, vGap));
panel.setOpaque(true);
panel.setBackground(bColor.darker().darker());
JButton swapperButton = new JButton("Next");
swapperButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
CardLayout cardLayout = (CardLayout) cardPanel.getLayout();
cardLayout.next(cardPanel);
}
});
panel.add(swapperButton);
return panel;
}
private void addComp(JPanel panel, JComponent comp
, int x, int y, int gWidth
, int gHeight, int fill
, double weightx, double weighty) {
gbc.gridx = x;
gbc.gridy = y;
gbc.gridwidth = gWidth;
gbc.gridheight = gHeight;
gbc.fill = fill;
gbc.weightx = weightx;
gbc.weighty = weighty;
panel.add(comp, gbc);
}
public static void main(String[] args) {
Runnable runnable = new Runnable(){
#Override
public void run() {
new LayoutExample().displayGUI();
}
};
EventQueue.invokeLater(runnable);
}
}
OUTPUT :

There are a number of ways in a Swing GUI to provide a separation between components, and white space around components:
JToolBar has the methods addSeparator() & addSeparator(Dimension).
JMenu uses a spacing component better suited to menus, available through addSeparator().
But more generally, look to:
The spacing as can be defined in the layout constructors.
Borders.
Here is an example of using the layout separator hGap & vGap values & borders (specifically an EmptyBorder) to provide 'white' (actually shown as red to make it very obvious) space. Adjust the spinners to see the result.
import java.awt.*;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import javax.swing.event.*;
public class WhiteSpace {
private JPanel gui = null;
private BorderLayout mainLayout =
new BorderLayout(0, 0);
private final FlowLayout buttonLayout =
new FlowLayout(FlowLayout.CENTER, 0, 0);
private final JPanel buttonPanel = new JPanel(buttonLayout);
private final SpinnerNumberModel hModel =
new SpinnerNumberModel(0, 0, 15, 1);
private final SpinnerNumberModel vModel =
new SpinnerNumberModel(0, 0, 15, 1);
private final SpinnerNumberModel hBorderModel =
new SpinnerNumberModel(0, 0, 15, 1);
private final SpinnerNumberModel vBorderModel =
new SpinnerNumberModel(0, 0, 15, 1);
private ChangeListener changeListener;
public Container getGui() {
if (gui == null) {
gui = new JPanel(mainLayout);
gui.setBackground(Color.RED);
JTree tree = new JTree();
tree.setVisibleRowCount(10);
for (int ii = tree.getRowCount(); ii > -1; ii--) {
tree.expandRow(ii);
}
gui.add(new JScrollPane(
tree,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER),
BorderLayout.LINE_START);
gui.add(new JScrollPane(new JTextArea(10, 30)));
gui.add(buttonPanel, BorderLayout.PAGE_START);
changeListener = (ChangeEvent e) -> {
int hGap = hModel.getNumber().intValue();
int vGap = vModel.getNumber().intValue();
int hBorder = hBorderModel.getNumber().intValue();
int vBorder = vBorderModel.getNumber().intValue();
adjustWhiteSpace(hGap, vGap, hBorder, vBorder);
};
addModel("H Gap", hModel);
addModel("V Gap", vModel);
addModel("H Border", hBorderModel);
addModel("V Border", vBorderModel);
}
return gui;
}
private void addModel(String label, SpinnerNumberModel model) {
buttonPanel.add(new JLabel(label));
final JSpinner spinner = new JSpinner(model);
spinner.addChangeListener(changeListener);
buttonPanel.add(spinner);
}
private void adjustWhiteSpace(
int hGap, int vGap, int hBorder, int vBorder) {
mainLayout.setHgap(hGap);
mainLayout.setVgap(vGap);
buttonLayout.setHgap(hGap);
gui.setBorder(new EmptyBorder
(vBorder, hBorder, vBorder, hBorder));
Container c = gui.getTopLevelAncestor();
if (c instanceof Window) {
Window w = (Window) c;
w.pack();
}
}
public static void main(String[] args) {
Runnable r = () -> {
WhiteSpace ws = new WhiteSpace();
Container gui1 = ws.getGui();
JFrame f = new JFrame("White (OK Red) Space");
f.add(gui1);
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setResizable(false);
f.pack();
f.setVisible(true);
};
SwingUtilities.invokeLater(r);
}
}

When you use BoxLayout, Box.createVerticalGlue() method can help you to make some white space.
Another method is BorderFactory.createEmptyBorder(int top, int left, int bottom, int right). It can help you to make some white space around component.
Thanks for Andrew Thompson's remind.I've revised BoxLayout in recent days and I find that Box.createVerticalGlue() can add some white space depend on the panel's size and you can not set the explicit pixel value of the length of white space.But Box.createVerticalStrut() can do that. Here is a MCTaRE and show the effect of those two methods.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
public class WhiteSpace extends JFrame{
static WhiteSpace whiteSpace;
DemoPanel demoPanel;
boolean withGlue;
JSpinner spinner;
public WhiteSpace(){
initialWindow();
demoPanel = new DemoPanel();
ActionPanel actionPanel = new ActionPanel();
setLayout(new BorderLayout());
getContentPane().add(actionPanel,BorderLayout.NORTH);
getContentPane().add(demoPanel,BorderLayout.CENTER);
setVisible(true);
}
public void initialWindow(){
setSize(220, 300);
setTitle("White Space");
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
//Show the window in the middle of the screen
}
/**
* #param args
*/
public static void main(String[] args) {
Runnable runnable = new Runnable() {
#Override
public void run() {
whiteSpace = new WhiteSpace();
}
};
SwingUtilities.invokeLater(runnable);
}
class DemoPanel extends JPanel{
//Show the vertical white space between label1 and label2
JLabel label1;
JLabel label2;
public void initialDemoPanel(){
setBorder(BorderFactory.createTitledBorder(getBorder(), "DemoPanel", TitledBorder.LEADING, TitledBorder.TOP, new Font("Default",Font.PLAIN,10), Color.gray));
setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
label1 = new JLabel("This is first line");
label2 = new JLabel("This is second line");
}
public DemoPanel(){
initialDemoPanel();
add(label1);
if(withGlue){
add(Box.createVerticalGlue());
}
add(label2);
}
public DemoPanel(int strutValue){
initialDemoPanel();
add(label1);
add(Box.createVerticalStrut(strutValue));
add(label2);
}
}
class ActionPanel extends JPanel{
public ActionPanel(){
setBorder(BorderFactory.createTitledBorder(getBorder(), "ActionPanel", TitledBorder.LEADING, TitledBorder.TOP, new Font("Default",Font.PLAIN,10), Color.gray));
setLayout(new BoxLayout(this,BoxLayout.X_AXIS));
JRadioButton glueButton = new JRadioButton("With Glue");
glueButton.addActionListener(new glueButtonListener());
add(glueButton);
add(Box.createHorizontalStrut(10));
//To create horizontal white space
JLabel strutLabel = new JLabel("Strut Value");
add(strutLabel);
spinner = new JSpinner(new SpinnerNumberModel(0,0,50,1));
spinner.addChangeListener(new spinnerListener());
add(spinner);
//public SpinnerNumberModel(Number value,Comparable minimum,Comparable maximum,Number stepSize)
}
}
class glueButtonListener implements ActionListener{
#Override
public void actionPerformed(ActionEvent e) {
spinner.setValue(new Integer(0));
withGlue = (withGlue == true ? false:true);
whiteSpace.getContentPane().remove(demoPanel);
demoPanel = new DemoPanel();
whiteSpace.getContentPane().add(demoPanel,BorderLayout.CENTER);
whiteSpace.getContentPane().validate();
}
}
class spinnerListener implements ChangeListener{
#Override
public void stateChanged(ChangeEvent e) {
int strutValue = (Integer) spinner.getValue();
whiteSpace.getContentPane().remove(demoPanel);
demoPanel = new DemoPanel(strutValue);
whiteSpace.getContentPane().add(demoPanel,BorderLayout.CENTER);
whiteSpace.getContentPane().validate();
}
}
}
Box.createHorizontalGlue() and Box.createHorizontalStrut(int height) can be used too. Besides, Box.createRigidArea(Dimension d) has the ability too create white space too.

MigLayout has multiple ways of creating space. (A space is called a gap in this layout.)
Gaps can be created at the highest level with layout constraints, it is possible to
create gaps between rows and column and gaps can be also set between individual
components with component constraints. There are also specific gaps around the borders
of a container called insets which have their own specific keyword to be set.
The following example creates all these kinds of gaps:
package com.zetcode;
import java.awt.EventQueue;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import net.miginfocom.swing.MigLayout;
public class MigLayoutGaps2 extends JFrame {
public MigLayoutGaps2() {
initUI();
setTitle("Gaps");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
}
private void initUI() {
JPanel base = new JPanel(new MigLayout("flowy, ins 30, gap 15"));
setContentPane(base);
JPanel pnl1 = new JPanel();
pnl1.setBorder(
BorderFactory.createTitledBorder("Grid gaps")
);
pnl1.setLayout(new MigLayout("gap 5 5, ins 10, wrap 3"));
pnl1.add(new JButton("1"));
pnl1.add(new JButton("2"));
pnl1.add(new JButton("3"));
pnl1.add(new JButton("4"));
pnl1.add(new JButton("5"));
pnl1.add(new JButton("6"));
JPanel pnl2 = new JPanel();
pnl2.setBorder(
BorderFactory.createTitledBorder("Column gaps")
);
pnl2.setLayout(new MigLayout("wrap 3", "[]10[]"));
JLabel lbl1 = new JLabel();
lbl1.setBorder(
BorderFactory.createEtchedBorder()
);
JLabel lbl2 = new JLabel();
lbl2.setBorder(
BorderFactory.createEtchedBorder()
);
JLabel lbl3 = new JLabel();
lbl3.setBorder(
BorderFactory.createEtchedBorder()
);
pnl2.add(lbl1, "w 40, h 110");
pnl2.add(lbl2, "w 40, h 110");
pnl2.add(lbl3, "w 40, h 110");
JPanel pnl3 = new JPanel();
pnl3.setBorder(
BorderFactory.createTitledBorder("Row gaps")
);
pnl3.setLayout(new MigLayout("wrap", "", "[]15[]"));
JLabel lbl4 = new JLabel();
lbl4.setBorder(
BorderFactory.createEtchedBorder()
);
JLabel lbl5 = new JLabel();
lbl5.setBorder(
BorderFactory.createEtchedBorder()
);
JLabel lbl6 = new JLabel();
lbl6.setBorder(
BorderFactory.createEtchedBorder()
);
pnl3.add(lbl4, "w 150, h 20");
pnl3.add(lbl5, "w 150, h 20");
pnl3.add(lbl6, "w 150, h 20");
JPanel pnl4 = new JPanel();
pnl4.setBorder(
BorderFactory.createTitledBorder("Component gaps")
);
pnl4.setLayout(new MigLayout());
pnl4.add(new JLabel("Name:"), "gapright 5");
pnl4.add(new JTextField(10), "gapbottom 20, gaptop 20");
base.add(pnl1);
base.add(pnl2);
base.add(pnl3);
base.add(pnl4);
pack();
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
MigLayoutGaps2 ex = new MigLayoutGaps2();
ex.setVisible(true);
}
});
}
}
We have four panels in the layout. Each of this panels has a MigLayout manager.
JPanel base = new JPanel(new MigLayout("flowy, ins 30, gap 15"));
This line creates container insets and vertical gaps between panels.
pnl1.setLayout(new MigLayout("gap 5 5, ins 10, wrap 3"));
Here we apply gaps for the whole grid structure and also set container gaps.
pnl2.setLayout(new MigLayout("wrap 3", "[]10[]"));
This line creates gaps between columns.
pnl3.setLayout(new MigLayout("wrap", "", "[]15[]"));
Row gaps are defined with this code.
pnl4.add(new JLabel("Name:"), "gapright 5");
pnl4.add(new JTextField(10), "gapbottom 20, gaptop 20");
Finally, it is possible to create gaps between individual components.

JGoodies FormLayout.
Author Karsten Lentzsch has a collection of presentations on UI design. In particular this PDF speaks to the need for aesthetic whitespace. Adding meaningful space while also paying attention to clutter separates the wheat from the chaff.

Whenever I have this issue, I just use JPanels. For example in a GridLayout:
JFrame frame = new JFrame;
frame.setLayout(new GridLayout(2, 0));
//We want the bottom left to be blank
frame.add(new JLabel("Top Left"));
frame.add(new JLabel("Top Right"));
//This is the position we want empty
frame.add(new JPanel());
//Now we can continue with the rest of the script