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Java awt border for for JPanel not working

For some reason my borders aren't showing for my panels and i am unsure why, is there something i'm missing?
I have a main class which runs the frame class as well as other classes separate to the GUI
This is the code from my frame class:
import javax.swing.*;
import java.awt.*;
public class Frame
{
public static int xsize;
public static int ysize;
public static void main()
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
JFrame frame = new MainFrame("Warlock of Firetop Mountain");
//Implementing Toolkit to allow computer to get dimensions of screen and assign them to two int values
Toolkit tk = Toolkit.getDefaultToolkit();
Frame.xsize = (int) tk.getScreenSize().getWidth();
Frame.ysize = (int) tk.getScreenSize().getHeight();
frame.setTitle("Warlock of Firetop Mountain");
frame.setSize(new Dimension(xsize, ysize));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(true);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
The frame.java takes its panels from MainFrame.java:
import javax.swing.*;
import java.awt.*;
public class MainFrame extends JFrame
{
private Panel1 storyPanel;
private Panel2 statsPanel;
private Panel3 commandsPanel;
public MainFrame(String title)
{
super(title);
// Setting Layout
setLayout(new BorderLayout());
storyPanel = new Panel1();
statsPanel = new Panel2();
commandsPanel = new Panel3();
Container p = getContentPane();
p.add(storyPanel, BorderLayout.WEST);
p.add(statsPanel, BorderLayout.EAST);
p.add(commandsPanel, BorderLayout.SOUTH);
}
}
This calls up my three panels which look like this:
import javax.swing.JPanel;
import javax.swing.BorderFactory;
import java.awt.Dimension;
import java.awt.Color;
public class Panel1 extends JPanel
{
public Panel1()
{
//Set size of Panel1
int xsizeP1 = (Frame.xsize / 2);
int ysizeP1 = (Frame.ysize / 3 * 2);
setPreferredSize(new Dimension(xsizeP1, ysizeP1));
setBorder(BorderFactory.createLineBorder(Color.black));
}
}
when the code runs the window launches as full screen but no borders or possibly panels are visible.
Thanks for any help, sorry if my questions are tedious, i'm relatively new to programming.
This is roughly what i want my panels to look like, eventually ill add in components to the panel and use GridBagConstraints to control the formatting

// this creates the JPanels and sets their preferred sizes
JFrame frame = new MainFrame("Warlock of Firetop Mountain");
//this sets your size static contents -- after the above's been done!
Toolkit tk = Toolkit.getDefaultToolkit();
Frame.xsize = (int) tk.getScreenSize().getWidth();
Frame.ysize = (int) tk.getScreenSize().getHeight();
You're setting preferred sizes of all your JPanels to 0, 0, and so you're not seeing any borders. Your sizing is being created after you've created your JPanels, and this method of sizing looks dangerous to me.
OK, thanks for posting an image of the desired GUI. My recommendations are:
First and foremost, don't try setting sizes as you're doing.
Instead, let the components and their layout managers size themselves.
Nest JPanels, each using its own layout manager to allow you to simply create complex GUI's.
When displaying images / ImageIcons, let them set the sizes of things as well.
If your GUI starts up with no icons displaying, consider creating a blank ImageIcon with a blank image of the right size as a placeholder icon.
For example, something like this:
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Insets;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.image.BufferedImage;
import javax.swing.*;
#SuppressWarnings("serial")
public class TomGuiPanel extends JPanel {
// rows and cols for jtextarea
private static final int CURRENT_AREA_ROWS = 20;
private static final int CURRENT_AREA_COLS = 40;
// columns for command jtextfied
private static final int COMMANDS_FIELD_COLS = 50;
// size of GUI component gaps
private static final int EB_GAP = 3;
private static final int NUMBER_OF_OPTIONS = 5;
// number if ImageIcons displayed within the user image char JList
private static final int CHAR_IMG_VISIBLE_ROWS = 5;
// a guess of the width of the largest image icon in the JList
// You'd use a different number
private static final int USER_IMG_CHAR_IMG_WIDTH = 70;
private JTextArea currentTextArea = new JTextArea(CURRENT_AREA_ROWS, CURRENT_AREA_COLS);
private JTextField commandsField = new JTextField(COMMANDS_FIELD_COLS);
private EnterAction enterAction = new EnterAction("Enter");
private DefaultListModel<Icon> charImgListModel = new DefaultListModel<>();
private JList<Icon> charImgList = new JList<>(charImgListModel);
public TomGuiPanel() {
JPanel topBtnPanel = new JPanel(new GridLayout(1, 0, EB_GAP, EB_GAP));
String[] btnTexts = { "Inventory", "Options", "Save", "Load" };
for (String txt : btnTexts) {
topBtnPanel.add(new JButton(txt));
}
JPanel characteristicsPanel = new JPanel(new GridBagLayout());
addCharacteristics(characteristicsPanel, "HP", 20, 0);
addCharacteristics(characteristicsPanel, "Attack", 12, 1);
addCharacteristics(characteristicsPanel, "Defence", 8, 2);
addCharacteristics(characteristicsPanel, "Agility", 9, 3);
addCharacteristics(characteristicsPanel, "Luck", 2, 4);
JScrollPane imgListPane = new JScrollPane(charImgList);
imgListPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
charImgList.setVisibleRowCount(CHAR_IMG_VISIBLE_ROWS);
charImgList.setPrototypeCellValue(createProtoType());
JPanel rightPanel = new JPanel(new BorderLayout(EB_GAP, EB_GAP));
rightPanel.add(topBtnPanel, BorderLayout.PAGE_START);
rightPanel.add(imgListPane, BorderLayout.CENTER);
rightPanel.add(characteristicsPanel, BorderLayout.LINE_END);
JPanel optionsPanel = new JPanel(new GridLayout(1, 0));
for (int i = 0; i < NUMBER_OF_OPTIONS; i++) {
String text = "Option " + (i + 1);
optionsPanel.add(new JCheckBox(text));
}
currentTextArea.setWrapStyleWord(true);
currentTextArea.setLineWrap(true);
currentTextArea.setFocusable(false);
JScrollPane taScrollPane = new JScrollPane(currentTextArea);
taScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
JPanel centerPanel = new JPanel(new BorderLayout());
centerPanel.add(taScrollPane, BorderLayout.CENTER);
centerPanel.add(rightPanel, BorderLayout.LINE_END);
centerPanel.add(optionsPanel, BorderLayout.PAGE_END);
JPanel commandsPanel = new JPanel();
commandsPanel.setLayout(new BoxLayout(commandsPanel, BoxLayout.LINE_AXIS));
commandsPanel.add(commandsField);
commandsPanel.add(Box.createHorizontalStrut(EB_GAP));
commandsPanel.add(new JButton(enterAction));
commandsPanel.add(Box.createHorizontalStrut(EB_GAP));
commandsPanel.add(new JButton(new ExitAction("Exit", KeyEvent.VK_X)));
commandsField.setAction(enterAction); // use same action for button and
// text field
setBorder(BorderFactory.createEmptyBorder(EB_GAP, EB_GAP, EB_GAP, EB_GAP));
setLayout(new BorderLayout(EB_GAP, EB_GAP));
add(centerPanel, BorderLayout.CENTER);
add(commandsPanel, BorderLayout.PAGE_END);
}
private void addCharacteristics(JPanel cPanel, String text, int value, int row) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = row;
gbc.insets = new Insets(5, 5, 5, 5);
gbc.weightx = 1.0;
gbc.weighty = 0.0;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.anchor = GridBagConstraints.WEST;
cPanel.add(new JLabel(text), gbc);
gbc.insets.left = 20;
gbc.anchor = GridBagConstraints.EAST;
gbc.gridx = 1;
cPanel.add(new JLabel(String.valueOf(value)), gbc);
}
private Icon createProtoType() {
int w = USER_IMG_CHAR_IMG_WIDTH;
int h = w;
BufferedImage img = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
Icon icon = new ImageIcon(img);
return icon;
}
private class EnterAction extends AbstractAction {
public EnterAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
String text = commandsField.getText();
currentTextArea.append(text + "\n");
commandsField.selectAll();
}
}
private class ExitAction extends AbstractAction {
public ExitAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
Component source = (Component) e.getSource();
Window win = SwingUtilities.getWindowAncestor(source);
win.dispose();
}
}
private static void createAndShowGUI() {
TomGuiPanel mainPanel = new TomGuiPanel();
JFrame frame = new JFrame("Tom's GUI");
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(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
Would create this realizable GUI:
Note that the GUI is roughly made, has no functionality other than the enter and exit buttons.

Calling method from one class in other

I know that this kind of issue has been discussed here many times, but I'm confused. I'm totally beginner in Java and I honestly don't know what to do and I admit that I don't have that much time to read whole documentation provided by Oracle. Here's my problem:
I'm trying to program a GUI for my program that will be show interference of acoustic waves. Mathematical functionality doesn't matter in here. I've got two classes called Window and Sliders. Window is intended to be a 'main GUI class' and Sliders is supposed to inherit (?) from it.
This comes from another issue that I need to implement ActionListener in class Window and ChangeListener in Sliders class. I heard that one class can't implement several classes that's why I made two.
Now, I wrote a little bit chaotic those two classes, but I don't know how to combine them. It's really silly, but after C++ I'm pretty confused how to tell the program that it is supposed to show in one frame either buttons defined in Window class and sliders defined in Sliders class. Currently it shows only buttons I want to make it showing sliders too.
I'm very sorry for chaotic pseudo code, please help. Please, try to explain as simply as you can/possible. Please feel free to ignore overrided methods, they're not finished yet.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.*;
public class Window extends JFrame implements ActionListener
{
private JButton showChord, playSound, getSample, getPlot;
private JLabel chordInfo;
private JPanel basicFunctions;
public Window()
{
init();
}
private void init()
{
setVisible(true);
setSize(new Dimension(1000,500));
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
basicFunctions = new JPanel();
FlowLayout basicLayout = new FlowLayout();
basicFunctions.setLayout(basicLayout);
showChord = new JButton("Akord");
playSound = new JButton("Odtwórz");
getSample = new JButton("Pobierz dźwięk");
getPlot = new JButton("Pobierz wykres");
showChord.addActionListener(this);
playSound.addActionListener(this);
getSample.addActionListener(this);
getPlot.addActionListener(this);
basicFunctions.add(showChord);
basicFunctions.add(playSound);
basicFunctions.add(getSample);
basicFunctions.add(getPlot);
add(basicFunctions);
Sliders param = new Sliders();
}
public static void main(String[] args)
{
Window frame = new Window();
}
//Action Listener
#Override
public void actionPerformed(ActionEvent a)
{
Object event = a.getSource();
if(event == showChord)
{
}
else if(event == playSound)
{
}
else if(event == getSample)
{
}
else if(event == getPlot)
{
}
}
}
import java.awt.*;
import javax.swing.event.ChangeEvent;
import javax.swing.*;
import javax.swing.event.ChangeListener;
public class Sliders extends Window implements ChangeListener
{
private JPanel sliders, sliderSub;
private JTextField accAmplitude, accFrequency, accPhase;
private JSlider amplitude, frequency, phase;
private double amplitudeValue, frequencyValue, phaseValue;
public Sliders()
{
sliders = new JPanel();
sliders.setLayout(new FlowLayout());
amplitude = new JSlider(0,100,0);
amplitude.setMajorTickSpacing(10);
amplitude.setMinorTickSpacing(5);
amplitude.setPaintTicks(true);
amplitude.setPaintLabels(true);
frequency = new JSlider(0,10,0);
frequency.setMajorTickSpacing(1);
frequency.setMinorTickSpacing(1/10);
frequency.setPaintTicks(true);
frequency.setPaintLabels(true);
phase = new JSlider(0,1,0);
phase.setMinorTickSpacing(2/10);
phase.setPaintTicks(true);
phase.setPaintLabels(true);
accAmplitude = new JTextField();
accFrequency = new JTextField();
accPhase = new JTextField();
sliders.add(amplitude, BorderLayout.NORTH);
sliders.add(frequency, BorderLayout.CENTER);
sliders.add(phase, BorderLayout.SOUTH);
add(sliders);
}
#Override
public void stateChanged(ChangeEvent arg0)
{
}
}
I've done this so far, but those text fields just stopped showing sliders values and I don't know why. They are defined in the Parameters class and Window class. Can someone help? Additionally in the future I'd like to make those text fields editable so that you can set slider value by typing it in the text field.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.BevelBorder;
import javax.swing.event.*;
public class Window extends JPanel
{
private JMenuBar mainMenu = new JMenuBar();
private Plot plot = new Plot();
private Parameters param = new Parameters();
private JComboBox chooseChord = new JComboBox();
private JButton playSound = new JButton("Odtwórz");
private JButton getSample = new JButton("Pobierz dźwięk");
private JButton getPlot = new JButton("Pobierz wykres");
private JPanel mainPanel = new JPanel();
private JPanel subPanel = new JPanel();
private JPanel buttonsPanel = new JPanel();
private JPanel slidersPanel = new JPanel();
private JLabel chord = new JLabel("Akord:");
private JTextField aValue = new JTextField();
private JTextField fValue = new JTextField();
private JTextField pValue = new JTextField();
public Window()
{
mainPanel.setLayout(new FlowLayout());
buttonsPanel.setLayout(new BoxLayout(buttonsPanel, BoxLayout.Y_AXIS));
slidersPanel.setLayout(new BorderLayout());
subPanel.setLayout(new BorderLayout());
chooseChord.addItem("A");
chooseChord.addItem("A#");
chooseChord.addItem("Ab");
chooseChord.addItem("B");
chooseChord.addItem("Bb");
chooseChord.addItem("C");
chooseChord.addItem("C#");
chooseChord.addItem("Cb");
chooseChord.addItem("D");
chooseChord.addItem("D#");
chooseChord.addItem("E");
chooseChord.addItem("F");
chooseChord.addItem("F#");
buttonsPanel.add(chord);
buttonsPanel.add(chooseChord);
buttonsPanel.add(Box.createRigidArea(new Dimension(0,10)));
buttonsPanel.add(playSound);
buttonsPanel.add(Box.createRigidArea(new Dimension(0,10)));
buttonsPanel.add(getSample);
buttonsPanel.add(Box.createRigidArea(new Dimension(0,10)));
buttonsPanel.add(getPlot);
buttonsPanel.setBorder(BorderFactory.createTitledBorder("Menu"));
slidersPanel.add(param);
JMenu langMenu = new JMenu("Język");
mainMenu.add(langMenu);
subPanel.add(buttonsPanel, BorderLayout.NORTH);
subPanel.add(slidersPanel, BorderLayout.SOUTH);
mainPanel.add(subPanel);
mainPanel.add(plot);
add(mainPanel);
param.addAmplitudeListener(new ChangeListener()
{
public void stateChanged(ChangeEvent a)
{
double ampValue = param.getAmplitudeValue();
aValue.setText(String.valueOf(ampValue));
}
}
);
param.addFrequencyListener(new ChangeListener()
{
public void stateChanged(ChangeEvent f)
{
double frValue = param.getFrequencyValue();
fValue.setText(String.valueOf(frValue));
}
}
);
param.addPhaseListener(new ChangeListener()
{
public void stateChanged(ChangeEvent p)
{
double phValue = param.getPhaseValue();
pValue.setText(String.valueOf(phValue));
}
}
);
}
public JMenuBar getmainMenu()
{
return mainMenu;
}
private static void GUI()
{
Window mainPanel = new Window();
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.setJMenuBar(mainPanel.getmainMenu());
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
GUI();
}
}
);
}
}
class Parameters extends JPanel
{
private JPanel pane = new JPanel();
private JPanel ampPanel = new JPanel();
private JPanel frPanel = new JPanel();
private JPanel phPanel = new JPanel();
private JSlider amplitude = new JSlider(0,100,0);
private JSlider frequency = new JSlider(0,10000,0);
private JSlider phase = new JSlider(0,180,0);
private JLabel pLabel = new JLabel("Faza");
private JLabel aLabel = new JLabel("Amplituda (dB)");
private JLabel fLabel = new JLabel("Częstotliwość (Hz)");
private JTextField preciseAmplitude = new JTextField(3);
private JTextField preciseFrequency = new JTextField(4);
private JTextField precisePhase = new JTextField(3);
public Parameters()
{
preciseAmplitude.setEditable(true);
preciseFrequency.setEditable(true);
precisePhase.setEditable(true);
pane.setLayout(new BoxLayout(pane, BoxLayout.PAGE_AXIS));
ampPanel.setLayout(new FlowLayout());
frPanel.setLayout(new FlowLayout());
phPanel.setLayout(new FlowLayout());
amplitude.setMajorTickSpacing(10);
amplitude.setMinorTickSpacing(5);
amplitude.setPaintTicks(true);
amplitude.setPaintLabels(true);
frequency.setMajorTickSpacing(2000);
frequency.setMinorTickSpacing(100);
frequency.setPaintTicks(true);
frequency.setPaintLabels(true);
phase.setMajorTickSpacing(2/10);
phase.setPaintTicks(true);
phase.setPaintLabels(true);
setBorder(BorderFactory.createTitledBorder("Parametry fali"));
ampPanel.add(aLabel);
ampPanel.add(preciseAmplitude);
pane.add(ampPanel);
pane.add(Box.createRigidArea(new Dimension(0,5)));
pane.add(amplitude);
pane.add(Box.createRigidArea(new Dimension(0,10)));
frPanel.add(fLabel);
frPanel.add(preciseFrequency);
pane.add(frPanel);
pane.add(Box.createRigidArea(new Dimension(0,5)));
pane.add(frequency);
pane.add(Box.createRigidArea(new Dimension(0,10)));
phPanel.add(pLabel);
phPanel.add(precisePhase);
pane.add(phPanel);
pane.add(Box.createRigidArea(new Dimension(0,5)));
pane.add(phase);
pane.add(Box.createRigidArea(new Dimension(0,10)));
add(pane);
}
public int getAmplitudeValue()
{
return amplitude.getValue();
}
public int getFrequencyValue()
{
return frequency.getValue();
}
public int getPhaseValue()
{
return phase.getValue();
}
public void addAmplitudeListener(ChangeListener ampListener)
{
amplitude.addChangeListener(ampListener);
}
public void addFrequencyListener(ChangeListener frListener)
{
frequency.addChangeListener(frListener);
}
public void addPhaseListener(ChangeListener phListener)
{
phase.addChangeListener(phListener);
}
}
class Plot extends JPanel
{
private JPanel componentWave = new JPanel();
private JPanel netWave = new JPanel();
private JLabel componentLabel = new JLabel("Fale składowe");
private JLabel netLabel = new JLabel("Fala wypadkowa");
private JLabel wave = new JLabel("Wybierz falę składową");
private JPanel labels = new JPanel();
private JComboBox chooseWave = new JComboBox();
public Plot()
{
labels.setLayout(new BoxLayout(labels, BoxLayout.PAGE_AXIS));
componentWave.setBackground(new Color(255,255,255));
netWave.setBackground(new Color(255,255,255));
componentWave.setBorder(BorderFactory.createBevelBorder(BevelBorder.LOWERED));
netWave.setBorder(BorderFactory.createBevelBorder(BevelBorder.LOWERED));
componentWave.setPreferredSize(new Dimension(400,200));
netWave.setPreferredSize(new Dimension(400,200));
labels.add(wave);
labels.add(Box.createRigidArea(new Dimension(0,10)));
labels.add(chooseWave);
labels.add(componentLabel);
labels.add(componentWave);
labels.add(Box.createRigidArea(new Dimension(0,20)));
labels.add(netLabel);
labels.add(netWave);
add(labels);
}
}

Window is intended to be a 'main GUI class' and Sliders is supposed to inherit (?) from it.
Nope: this is a misuse of inheritance and will only lead to problems since the Windows instance that Sliders inherently is, is completely distinct from the displayed Windows instance. What you need to do is to pass references.
For example, the following code uses outside classes for the JButton and JMenuItem Actions (Actions are like ActionListeners on steroids), and uses a class that holds a JSlider that allows itside classes to attach listeners to the slider.
import java.awt.Component;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class Foo extends JPanel {
private static final long serialVersionUID = 1L;
private Action helloAction = new HelloAction("Hello", KeyEvent.VK_H);
private Action exitAction = new ExitAction("Exit", KeyEvent.VK_X);
private JMenuBar menuBar = new JMenuBar();
private JTextField sliderValueField = new JTextField(10);
private Bar bar = new Bar();
public Foo() {
sliderValueField.setEditable(false);
sliderValueField.setFocusable(false);
add(new JButton(helloAction));
add(new JButton(exitAction));
add(new JLabel("Slider Value: "));
add(sliderValueField);
add(bar);
JMenu fileMenu = new JMenu("File");
fileMenu.setMnemonic(KeyEvent.VK_F);
fileMenu.add(new JMenuItem(exitAction));
fileMenu.add(new JMenuItem(helloAction));
menuBar.add(fileMenu);
bar.addSliderListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent e) {
int sliderValue = bar.getSliderValue();
sliderValueField.setText(String.valueOf(sliderValue));
}
});
}
public JMenuBar getJMenuBar() {
return menuBar;
}
private static void createAndShowGui() {
Foo mainPanel = new Foo();
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.setJMenuBar(mainPanel.getJMenuBar());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class HelloAction extends AbstractAction {
public HelloAction(String name, int mnemonic) {
super(name); // sets name property and gives button its title
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(null, "Hello!");
}
}
class ExitAction extends AbstractAction {
private static final long serialVersionUID = 1L;
public ExitAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
Component component = (Component) e.getSource();
Window win = SwingUtilities.getWindowAncestor(component);
if (win == null) {
// if no window, then a JMenuItem held in a JPopupMenu
JPopupMenu popup = (JPopupMenu) component.getParent();
component = popup.getInvoker();
win = SwingUtilities.getWindowAncestor(component);
}
win.dispose();
}
}
class Bar extends JPanel {
private JSlider slider = new JSlider(0, 100, 50);
public Bar() {
slider.setPaintLabels(true);
slider.setPaintTicks(true);
slider.setMajorTickSpacing(20);
slider.setMinorTickSpacing(5);
slider.setSnapToTicks(true);
setBorder(BorderFactory.createTitledBorder("Slider Panel"));
add(slider);
}
public int getSliderValue() {
return slider.getValue();
}
// one way to let outside classes listen for changes
public void addSliderListener(ChangeListener listener) {
slider.addChangeListener(listener);
}
}
You ask about decimal labels, and yes this can be done but requires use of a label table. For example,
JSlider slider = new JSlider(0, 100, 50);
slider.setPaintLabels(true);
slider.setPaintTicks(true);
slider.setMajorTickSpacing(20);
slider.setMinorTickSpacing(2);
Dictionary<Integer, JLabel> labels = new Hashtable<>();
for (int i = 0; i <= 100; i += 20) {
labels.put(i, new JLabel(String.format("%.1f", i / 200.0)));
}
slider.setLabelTable(labels);
Which displays as:
You would also have to translate the value back from int to its corresponding floating point number.

How do I resize these panels in my JFrame?

I'm creating a chess game where the main panel is using BorderLayout, there is a panel at NORTH for buttons, a panel at CENTER for the board itself (set to GridLayout) and a sidebar at East.
I have made the JFrame unresizable and I'd like the chessboard to fit the panels in so that the East panel is a lot wider (maybe 200 pixels) and the board remains a square. I can't figure out how to change the sizes of these components individually.
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
public class GameWindow extends JFrame {
private final JPanel playArea = new JPanel(new BorderLayout(3,3));
private final JButton[][] boardSquares = new JButton[8][8];
private final JPanel board;
private final JPanel sidebar = new JPanel();
private final JLabel message = new JLabel("Game by ...");
public GameWindow() {
playArea.setBorder(new EmptyBorder(5, 5, 5, 5));
JToolBar tools = new JToolBar();
tools.setFloatable(false);
playArea.add(tools, BorderLayout.PAGE_START);
tools.add(new JButton("New Game"));
tools.add(new JButton("Save"));
tools.add(new JButton("Restore"));
tools.addSeparator();
tools.add(new JButton("Resign"))
tools.addSeparator();
tools.add(message);
board = new JPanel(new GridLayout(0, 8));
board.setBorder(new LineBorder(Color.BLACK));
playArea.add(board, BorderLayout.CENTER);
playArea.add(sidebar, BorderLayout.EAST);
Insets buttonMargin = new Insets(0,0,0,0);
for (int i = 0; i < boardSquares.length; i++) {
for (int j = 0; j < boardSquares[i].length; j++) {
JButton square = new JButton();
square.setMargin(buttonMargin);
if ((i+j)%2 == 0) {
square.setBackground(Color.WHITE);
}
else {
square.setBackground(Color.BLACK);
}
board.setSize(600, 600);
board.add(boardSquares[j][i] = square);
}
}
}
public final JComponent getChessBoard() {
return board;
}
public final JComponent getGui() {
return playArea;
}
public static void main(String[] args) {
GameWindow window = new GameWindow();
JFrame frame = new JFrame("Checkers");
frame.setResizable(false);
frame.add(window.getGui());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
frame.setSize(800, 800);
frame.setVisible(true);
}
}

Firstly, since JDK 1.4, Java is encouraging the use of BorderLayout constants as BorderLayout.PAGE_START, BorderLayout.LINE_START, BorderLayout.CENTER, BorderLayout.LINE_END and BorderLayout.PAGE_END over the latter used by you.
Secondly you can simply override, the getPreferredSize() of the said JPanel, in order for it to give, some size that you feel like will work for your use case. Use of setPreferredSize() is restricted, since, not all LayoutManagers use to respect the Dimension specified by it.
Hence you could do something like:
private final JPanel sidebar = new JPanel() {
#Override
public Dimension getPreferredSize() {
return new Dimension(100, 100);
}
};
You can try this modified code:
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
public class GameWindow extends JFrame {
private final JPanel playArea = new CustomPanel(710, 710);
private final JButton[][] boardSquares = new JButton[8][8];
private final JPanel board;
private final JPanel sidebar = new CustomPanel(100, 100);
private final JLabel message = new JLabel("Game by ...");
public GameWindow() {
playArea.setLayout(new BorderLayout(3,3));
playArea.setBorder(new EmptyBorder(5, 5, 5, 5));
JToolBar tools = new JToolBar();
tools.setFloatable(false);
playArea.add(tools, BorderLayout.PAGE_START);
tools.add(new JButton("New Game"));
tools.add(new JButton("Save"));
tools.add(new JButton("Restore"));
tools.addSeparator();
tools.add(new JButton("Resign"));
tools.addSeparator();
tools.add(message);
board = new CustomPanel(600, 600);
board.setLayout(new GridLayout(0, 8));
board.setBorder(new LineBorder(Color.BLACK));
playArea.add(board, BorderLayout.CENTER);
playArea.add(sidebar, BorderLayout.LINE_START);
Insets buttonMargin = new Insets(0,0,0,0);
for (int i = 0; i < boardSquares.length; i++) {
for (int j = 0; j < boardSquares[i].length; j++) {
JButton square = new JButton();
square.setOpaque(true);
square.setMargin(buttonMargin);
if ((i+j)%2 == 0) {
square.setBackground(Color.WHITE);
}
else {
square.setBackground(Color.BLACK);
}
board.add(boardSquares[j][i] = square);
}
}
}
private class CustomPanel extends JPanel {
private int width;
private int height;
public CustomPanel(int width, int height) {
this.width = width;
this.height = height;
setOpaque(true);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(width, height);
}
}
public final JComponent getChessBoard() {
return board;
}
public final JComponent getGui() {
return playArea;
}
public static void main(String[] args) {
GameWindow window = new GameWindow();
JFrame frame = new JFrame("Checkers");
frame.setResizable(false);
frame.setContentPane(window.getGui());
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLocationByPlatform(true);
frame.pack();
frame.setVisible(true);
}
}
Moreover, before setting the background of JButton, it would be wise to call button.setOpaque(true) property.

It's not difficult to set the size of a JPanel. Just call setPreferredSize(). In your case to resize your East JPanel, call:
sidebar.setPreferredSize(new Dimension(200, 200));
After that, your LayoutManager will set the size of your JPanel to 200,200.
To your other JPanel, board: It's impossible to make a Component (like a JPanel) remaining a square. They always fit into rectangles. You would need to make your own subclass of JComponent and only paint everything in the square, and leave the rest transparent. Therefore, overwrite the method JComponent.paintComponent(Graphics).

JPanel not appearing when added to parent JPanel

I'm dumbfounded here. I have a JPanel (defBoardPanel) that I'm adding to a parent JPanel (GamePanel) as follows:
public GamePanel(SetupBoard sb) {
this.setLayout(new BorderLayout());
// this.setBackground(Color.yellow);
JPanel defBoardPanel = new JPanel();
defBoardPanel.setBackground(Color.yellow);
for (int r = 0; r < sb.boardSize; r++){
for (int c = 0; c < sb.boardSize; c++){
Cell c = new Cell(r, c);
c.label.setOpaque(true);
if (sb.getCell(r, c).status == sb.getCell(r,c).status.occupied){
c.label.setBackground(Color.black);
System.out.println("LABEL IS OCCUPIED");
}
else {
c.label.setBackground(Color.white);
}
defBoardPanel.add(c.label);
}
}
defBoardPanel.revalidate();
defBoardPanel.setVisible(true);
this.add(defBoardPanel, BorderLayout.WEST);
this.revalidate();
this.setVisible(true);
This panel is to be added to a JFrame (MainFrame), which is shown below. When the application is launched, the JFrame displays a different type of Panel (SetupBoard), with which the user sets up their game board. When they click "accept", the StartGame() method of the MainFrame is called, which should show the JPanels above.
public MainFrame() {
this.setLayout(new BorderLayout());
this.setSize(500, 500);
SetupBoard sb = new SetupBoard(10, this);
this.setContentPane(sb);
}
void startGame(SetupBoard sb){
GamePanel gp = new GamePanel(sb);
this.setContentPane(gp);
this.revalidate();
}
My issue is that the child panel (defBoardPanel) is not displaying. The GamePanel itself displays (which I've verified using the setBackground(Color.yellow) method you see commented out), but not the panel I've added onto it.
What stupid mistake am I overlooking here?
EDIT: startGame() is being called from within the SetupBoard class:
void startGame(){
mf.startGame(this);
}
where mf is a reference to the MainFrame that created the SetupBoard instance. The fact that the GamePanel displays at all confirms that this is being called correctly.

Seems to work ok if I trim the code I don't have. Most likely the issue is coming from what you are not showing us. Therefore, producing an SSCCE would greatly benefit you. Meanwhile, you can always take advantage (to find the differences with your code) of the following one, which is highly originated from yours (I filled some gaps as I could):
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class GamePanel extends JPanel {
private static final int COLS = 10;
private static final int ROWS = 10;
public GamePanel() {
this.setLayout(new BorderLayout());
// this.setBackground(Color.yellow);
JPanel defBoardPanel = new JPanel(new GridLayout(ROWS, COLS));
defBoardPanel.setBackground(Color.yellow);
for (int r = 0; r < ROWS; r++) {
for (int c = 0; c < COLS; c++) {
JLabel label = new JLabel((r + 1) + " " + (c + 1));
label.setOpaque(true);
if (Math.random() > 0.5) {
label.setBackground(Color.black);
label.setForeground(Color.WHITE);
System.out.println("LABEL IS OCCUPIED");
} else {
label.setBackground(Color.white);
}
defBoardPanel.add(label);
}
}
this.add(defBoardPanel, BorderLayout.WEST);
}
public static class MainFrame extends JFrame {
public MainFrame() {
this.setLayout(new BorderLayout());
this.setSize(500, 500);
}
void startGame() {
GamePanel gp = new GamePanel();
this.setContentPane(gp);
pack();
setVisible(true);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
MainFrame mainFrame = new MainFrame();
mainFrame.startGame();
}
});
}
}

This code sequence replaces the GamePanel after it has been added to MainFrame
public MainFrame() {
this.setLayout(new BorderLayout());
this.setSize(500, 500);
SetupBoard sb = new SetupBoard(10, this); // invokes startGame
this.setContentPane(sb); <----- GamePanel replaced here
}
void startGame(SetupBoard sb) {
GamePanel gp = new GamePanel(sb);
this.setContentPane(gp);
this.revalidate();
}

all individual panels are not shown inside root panel

I want to add multiple jpanels to jpanel.So i added a root panel to jscrollpane.and then added all individual jpanels to this root panel.I made jscrollpane's scrolling policy as needed.i.e HORIZONTAL_SCROLLBAR_AS_NEEDED,VERTICAL_SCROLLBAR_AS_NEEDED.
But the problem is all individual panels are not shown inside root panel.
Code:
JScrollPane scPanel=new JScrollPane();
JPanel rootPanel=new JPanel();
rootPanel.setLayout(new FlowLayout());
JPanel indPanel = new JPanel();
rootPanel.add(indPanel);
JPanel indPanel2 = new JPanel();
rootPanel.add(indPanel2);
//.....like this added indPanals to rootPanel.
scPanel.setViewPortView(rootPanel);
//scPanel.setHorizontalScrollPolicy(HORIZONTAL_SCROLLBAR_AS_NEEDED);
And one more thing is, as i scroll the scrollbar the panels are going out of jscrollpane area.
I am not able to see all individual panels,
Please suggest me.
Edit: code snippet from double post:
MosaicFilesStatusBean mosaicFilesStatusBean = new MosaicFilesStatusBean();
DefaultTableModel tableModel = null;
tableModel = mosaicFilesStatusBean.getFilesStatusBetweenDates(startDate, endDate);
if (tableModel != null) {
rootPanel.removeAll();
rootPanel.setLayout(new BoxLayout(rootPanel, BoxLayout.PAGE_AXIS));
for (int tempRow = 0; tempRow < tableModel.getRowCount(); tempRow++) {
int fileIdTemp = Integer.parseInt(tableModel.getValueAt(tempRow, 0).toString());
String dateFromTemp = tableModel.getValueAt(tempRow, 3).toString();
String dateToTemp = tableModel.getValueAt(tempRow, 4).toString();
int processIdTemp = Integer.parseInt(tableModel.getValueAt(tempRow, 5).toString());
int statusIdTemp = Integer.parseInt(tableModel.getValueAt(tempRow, 6).toString());
String operatingDateTemp = tableModel.getValueAt(tempRow, 7).toString();
MosaicPanel tempPanel =
new MosaicPanel(fileIdTemp, dateFromTemp, dateToTemp, processIdTemp, statusIdTemp, operatingDateTemp);
rootPanel.add(tempPanel);
}
rootPanel.revalidate();
}

The main reason, why you couldn't see your JPanel is that you are using FlowLayout as the LayoutManager for the rootPanel. And since your JPanel added to this rootPanel has nothing inside it, hence it will take it's size as 0, 0, for width and height respectively. Though using GridLayout such situation shouldn't come. Have a look at this code example attached :
import java.awt.*;
import javax.swing.*;
public class PanelAddition
{
private void createAndDisplayGUI()
{
JFrame frame = new JFrame("Panel Addition Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel contentPane = new JPanel();
contentPane.setLayout(new GridLayout(0, 1));
JScrollPane scroller = new JScrollPane();
CustomPanel panel = new CustomPanel(1);
contentPane.add(panel);
scroller.setViewportView(contentPane);
frame.getContentPane().add(scroller, BorderLayout.CENTER);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
for (int i = 2; i < 20; i++)
{
CustomPanel pane = new CustomPanel(i);
contentPane.add(pane);
contentPane.revalidate();
contentPane.repaint();
}
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new PanelAddition().createAndDisplayGUI();
}
});
}
}
class CustomPanel extends JPanel
{
public CustomPanel(int num)
{
JLabel label = new JLabel("" + num);
add(label);
}
#Override
public Dimension getPreferredSize()
{
return (new Dimension(200, 50));
}
}

Don't use FlowLayout for the rootPanel. Instead consider using BoxLayout:
JPanel rootPanel=new JPanel();
// if you want to stack JPanels vertically:
rootPanel.setLayout(new BoxLayout(rootPanel, BoxLayout.PAGE_AXIS));
Edit 1
Here's an SSCCE that's loosely based on your latest code posted:
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.util.Random;
import javax.swing.*;
#SuppressWarnings("serial")
public class PanelsEg extends JPanel {
private static final int MAX_ROW_COUNT = 100;
private Random random = new Random();
private JPanel rootPanel = new JPanel();
public PanelsEg() {
rootPanel.setLayout(new BoxLayout(rootPanel, BoxLayout.PAGE_AXIS));
JScrollPane scrollPane = new JScrollPane(rootPanel);
scrollPane.setPreferredSize(new Dimension(400, 400)); // sorry kleopatra
add(scrollPane);
add(new JButton(new AbstractAction("Foo") {
#Override
public void actionPerformed(ActionEvent arg0) {
foo();
}
}));
}
public void foo() {
rootPanel.removeAll();
// rootPanel.setLayout(new BoxLayout(rootPanel, BoxLayout.PAGE_AXIS)); // only need to set layout once
int rowCount = random.nextInt(MAX_ROW_COUNT);
for (int tempRow = 0; tempRow < rowCount ; tempRow++) {
int fileIdTemp = tempRow;
String data = "Data " + (tempRow + 1);
MosaicPanel tempPanel =
new MosaicPanel(fileIdTemp, data);
rootPanel.add(tempPanel);
}
rootPanel.revalidate();
rootPanel.repaint(); // don't forget to repaint if removing
}
private class MosaicPanel extends JPanel {
public MosaicPanel(int fileIdTemp, String data) {
add(new JLabel(data));
}
}
private static void createAndShowGui() {
PanelsEg mainPanel = new PanelsEg();
JFrame frame = new JFrame("PanelsEg");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
This SSCCE works, in that it easily shows removing and adding JPanels to another JPanel that is held by a JScrollPane. If you're still having a problem, you should modify this SSCCE so that it shows your problem.