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Multiple animations(threads) in a JPanel

I am trying to code a board game in Java.
I have 11 classes including Main. Board class which extends JPanel and draws the board image as well as the dice image. The class Player which extends JCoponent and implements Runnable(Thread). Every player instance is a pawn-animation that it is moving across the board. The player class draws the pawn on the board.
Pattern
How the code it looks like :
Board b=new Board();
Player p=new Player();
b.add(p);
JPanel panel=new JPanel();
panel.add(b);
add(panel); //adding the panel to the frame.
The problem is that I can't have more than one pawn simultaneously on the board. I have already tried to re-paint all the players (as non-animation) in another class but it didn't work. I also tried JLayeredPane but maybe I am doing something wrong. Unfortunately, I can't change the above pattern so don't make this suggestion.
Thank you in advance for your help.
P.S: I can't post any code because its huge.
P.P.S: more clarifications will be given, if you ask me.
EDIT: I reform my question. Is it possible to have two animations simultaneously on the same panel? if the answer is a yes ..how I can do that?

It's most likely possible to have many components moving all at once. Either use javax.swing.Timer ou SwingWorker for this to work.
Here is a quick example showing you this. It puts 16 pawns on a board and moves them randomly from one place to another.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.Image;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Random;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestAnimation {
private static final String PAWN_URL = "http://files.chesskidfiles.com/images_users/tiny_mce/BoundingOwl/bishop_happywhite.png";
private Image pawn;
private Map<Location, Pawn> pawnLocations = new HashMap<>();
private Board board;
private Timer timer;
private JLayeredPane glassPane;
public TestAnimation() {
try {
pawn = new ImageIcon(new URL(PAWN_URL)).getImage();
} catch (MalformedURLException e) {
e.printStackTrace();
}
}
private static class Location {
public final int row;
public final int col;
public Location(int row, int col) {
super();
this.row = row;
this.col = col;
}
#Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + col;
result = prime * result + row;
return result;
}
#Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
Location other = (Location) obj;
return (col == other.col && row == other.row);
}
}
private static class Cell extends JPanel {
private final Location location;
public Cell(Location location) {
super(new BorderLayout());
this.location = location;
setOpaque(true);
setBackground(((location.row + location.col) % 2) == 0 ? Color.WHITE : Color.BLACK);
}
#Override
protected void addImpl(Component comp, Object constraints, int index) {
while (getComponentCount() > 0) {
remove(0);
}
super.addImpl(comp, constraints, index);
}
}
private static class Board extends JPanel {
private Map<Location, Cell> cells = new HashMap<>();
public Board() {
super(new GridLayout(8, 8));
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 8; j++) {
Cell cell = new Cell(new Location(i, j));
add(cell);
cells.put(new Location(i, j), cell);
}
}
}
public void add(Pawn pawn, Location location) {
cells.get(location).add(pawn);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
public Cell getCell(Location location) {
return cells.get(location);
}
}
private class Pawn extends JComponent {
public Pawn() {
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(pawn, 0, 0, getWidth(), getHeight(), this);
}
}
protected void initUI() {
JFrame frame = new JFrame(TestAnimation.class.getSimpleName());
board = new Board();
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 2; j++) {
Location location = new Location(i, j);
Pawn aPawn = new Pawn();
board.add(aPawn, location);
pawnLocations.put(location, aPawn);
}
}
for (int i = 0; i < 8; i++) {
for (int j = 6; j < 8; j++) {
Location location = new Location(i, j);
Pawn aPawn = new Pawn();
board.add(aPawn, location);
pawnLocations.put(location, aPawn);
}
}
timer = new Timer(7000, new Animation());
timer.setInitialDelay(0);
timer.setRepeats(true);
timer.setCoalesce(false);
glassPane = new JLayeredPane();
glassPane.setOpaque(false);
frame.add(board);
frame.setGlassPane(glassPane);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
timer.start();
glassPane.setVisible(true);
}
public class Animation implements ActionListener {
private Map<Location, Pawn> futureLocations;
private Random random = new Random();
private Timer subTimer;
private List<Pawn> movingPawns;
private Map<Pawn, Point> originalCoordinates = new HashMap<>();
private Map<Pawn, Point> futureCoordinates = new HashMap<>();
#Override
public void actionPerformed(ActionEvent e) {
futureLocations = new HashMap<>();
movingPawns = new ArrayList<>();
for (Pawn p : pawnLocations.values()) {
int row = random.nextInt(8);
int col = random.nextInt(8);
Location location;
while (futureLocations.containsKey((location = new Location(row, col)))) {
row = random.nextInt(8);
col = random.nextInt(8);
}
futureLocations.put(location, p);
Cell futureCell = board.getCell(location);
futureCoordinates.put(p, SwingUtilities.convertPoint(futureCell, 0, 0, glassPane));
movingPawns.add(p);
}
for (Pawn p : movingPawns) {
Point locationInGlassPane = SwingUtilities.convertPoint(p.getParent(), 0, 0, glassPane);
glassPane.add(p);
p.setLocation(locationInGlassPane);
originalCoordinates.put(p, locationInGlassPane);
}
subTimer = new Timer(50, new AnimationSteps());
subTimer.setInitialDelay(0);
subTimer.setCoalesce(true);
subTimer.setRepeats(true);
subTimer.start();
}
public class AnimationSteps implements ActionListener {
private int step = 0;
#Override
public void actionPerformed(ActionEvent e1) {
if (step < 50 + 1) {
for (Pawn p : movingPawns) {
Point p1 = originalCoordinates.get(p);
Point p2 = futureCoordinates.get(p);
int x = (int) (p1.x + ((p2.x - p1.x) * (double) step / 50));
int y = (int) (p1.y + ((p2.y - p1.y) * (double) step / 50));
p.setLocation(x, y);
}
} else {
for (Entry<Location, Pawn> e : futureLocations.entrySet()) {
board.add(e.getValue(), e.getKey());
}
board.revalidate();
subTimer.stop();
pawnLocations = futureLocations;
}
step++;
}
}
}
public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException,
UnsupportedLookAndFeelException {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new TestAnimation().initUI();
}
});
}
}

Maybe your problem is trying to develop a program with a thread for each object, most popular games run with a single thread, two at most. The reason: It will be very complex to synchronize threads with each other, not to mention that your performance will be poor. Even the graphics engine in Java is single threaded and that means you won't have two threads drawing at the same time.

Java Swing Change Context of JTextField in several JPanels In 1 JFrame

Maybe you can help me out here :)
I want to "simulate" like say 10 machine-stations. In my JFrame/Container (I tried both) I put these 10 maschines ( = 10 JPanels containing x buttons, textfields, whatever of my desired design), and I want to have different informations on each one and change them for my needs.
I tried to change the value of a JTextField with an JButton (like setting the priority of the machine + 1. But I cannot distinguish between the 10 "priority up" buttons :(
How you do that? My idea was to speak somehow to the JPanel it came from but I can´t.
Container wizardFrame = new JFrame();
wizardFrame.setLayout(new GridLayout(2,5));
String Name;
for(int i = 1; i < 11; i++){
Name = "Maschine " + i;
fillWizardFrame(wizardFrame, Name, i);
}
wizardFrame.setVisible(true);
}
public void fillWizardFrame(Container wizardFrame, String Name, int i) {
JPanel MaschineId = new JPanel();
MaschineId.setLayout(new BorderLayout());
JTextField maschineName = new JTextField(Name ,10);
MaschineId.add(maschineName, BorderLayout.WEST);
maschinePrioritaet = new JTextField("20",10);
MaschineId.add(maschinePrioritaet,BorderLayout.CENTER);
JButton Higher = new JButton("Higher " + i); Higher.addActionListener(this);
MaschineId.add(Higher, BorderLayout.NORTH);
wizardFrame.add(MaschineId);
}
#Override
public void actionPerformed(ActionEvent event) {
if(event.getActionCommand().contains("Higher")){
System.out.println("Higher pressed " + event.getActionCommand());
}
// i tried .getID , .getSource etc... :/
}
I want to change the value of maschinePrioritaet with my "higher" button, but I can´t... This thing took me hours of searching and trying but wasn´t able to find something.
Thank you so much for your help!
Best, Andrea

You have to work more with objects and especially Views (like in MVC). A View represents an object, in this case it looks like some machine (which is a name, an id and a priority). So you need to create a machine panel that is attached to that model.
Here is something closer to that (but there are still many improvements to do):
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFormattedTextField;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class Wizard {
public Wizard() {
JFrame wizardFrame = new JFrame();
wizardFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
wizardFrame.setLayout(new GridLayout(2, 5));
String name;
for (int i = 1; i < 11; i++) {
name = "Maschine " + i;
MashinePanel mashinePanel = new MashinePanel(name, i);
wizardFrame.add(mashinePanel.getPanel());
}
wizardFrame.pack();
wizardFrame.setVisible(true);
}
public static class MashinePanel implements ActionListener {
private final String name;
private final int id;
private JTextField maschineNameTF;
private JFormattedTextField maschinePrioritaetTF;
private JButton higher;
private JPanel machinePanel;
public MashinePanel(String name, int i) {
super();
this.name = name;
this.id = i;
machinePanel = new JPanel();
machinePanel.setLayout(new BorderLayout());
maschineNameTF = new JTextField(name, 10);
machinePanel.add(maschineNameTF, BorderLayout.WEST);
maschinePrioritaetTF = new JFormattedTextField(20);
maschinePrioritaetTF.setColumns(10);
machinePanel.add(maschinePrioritaetTF, BorderLayout.CENTER);
higher = new JButton("Higher " + i);
higher.addActionListener(this);
machinePanel.add(higher, BorderLayout.NORTH);
}
public JPanel getPanel() {
return machinePanel;
}
public String getName() {
return name;
}
public int getId() {
return id;
}
#Override
public void actionPerformed(ActionEvent event) {
if (event.getActionCommand().contains("Higher")) {
Object value = maschinePrioritaetTF.getValue();
int priority = 20;
if (value instanceof Integer) {
priority = (Integer) value;
}
maschinePrioritaetTF.setValue(priority + 1);
}
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Wizard();
}
});
}
}

Trouble with CheckBox matrix, loops won't work

I am writing a program which will have multiple windows that will pass a value between them.
Currently I am testing one part of my program that is made out of 1-99 checkboxes. But when I want to check their states by clicking on a button it just doesn't work. Here's where the problem is:
public void actionPerformed(ActionEvent event) {
if(event.getSource() == okay) {
for(int i=0;i<box.length; i++){
for(int j=0;j<box.length; j++){
if((i==0)&&(j==0)) continue;
if(box[i][j].getState())
asdf.matra[i][j]=true;
System.out.println(box[i][j].getLabel() + " is " + asdf.matra[i][j]);
}
}
}
}
here's the main class:
public class asdf {
public static boolean matra[][] = new boolean[10][10];
public static void main(String arg[]) {
for(int ii=0;ii<matra.length; ii++){
for(int jj=0;jj<matra.length; jj++){
matra[ii][jj]=false;
}
}
new JFrameDemo();
}
}
and the other class:
import java.awt.*;
import java.awt.event.WindowEvent;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.ItemListener;
import java.awt.event.ItemEvent;
public class JFrameDemo extends Frame implements ActionListener, ItemListener {
Checkbox box[][] = new Checkbox[10][10];
Button okay;
JFrameDemo() {
enableEvents(AWTEvent.WINDOW_EVENT_MASK);
add(makePanel());
pack();
show();
}
private Panel makePanel() {
GridBagConstraints con = new GridBagConstraints();
Panel panel = new Panel();
GridBagLayout gridbag = new GridBagLayout();
panel.setLayout(gridbag);
for(int i=0;i<box.length; i++){
for(int j=0;j<box.length; j++){
if((i==0)&&(j==0)) continue;
box[i][j] = new Checkbox(i+j*10+"");
con.gridx = i;
con.gridy = j;
panel.add(box[i][j],con);
}
}
okay = new Button("Unesi");
con.gridx = 10;
con.gridy = 10;
panel.add(okay,con);
return(panel);
}
public void actionPerformed(ActionEvent event) {
if(event.getSource() == okay) {
for(int i=0;i<box.length; i++){
for(int j=0;j<box.length; j++){
if((i==0)&&(j==0)) continue;
if(box[i][j].getState())
asdf.matra[i][j]=true;
System.out.println(box[i][j].getLabel() + " is " + asdf.matra[i][j]);
}
}
}
}
public void itemStateChanged(ItemEvent event) {
}
public void processWindowEvent(WindowEvent event) {
if(event.getID() == WindowEvent.WINDOW_CLOSING)
System.exit(0);
}
}
The program is running without any errors, but the console isn't giving any results. It is supposed to pass value to the global variable also. I think there's an issues with nested fors.

You are forgetting to add the ActionListener to the button.
okay = new Button("Unesi");
okay.addActionListener(this);

How to show a message over leading selection cell in JTable?

I have a JTable with a custom ListSelectionModel, which contains a custom selection mode. This selection mode ensures that a selection is only made in one row, but with multiple cells. When a user clicks selects some cells in the table, the selected cells are all in the same row as the first selected cell.
Now I want to create a small message above the upper-right corner of the leading selection cell, which displays some data, i.e. the count of the selected cells. The message should be moved when the leading selection is changed.
But how do I do that? It is not a Tooltip as it is intended to be shown when user clicks into the table and selects cells and not by hovering over it.
Any suggestions?
best regards,
htz

Alternatively (not very pretty but works quite well), you can take advantage of the fact that JTable is a JComponent like all others and therefore you can add child components to it. All you have to do, is make sure to size and locate properly your component (this is only because JTable uses a null-layout).
Here is a small demo with a JLabel that displays the number of selected items. The label is automatically positioned on the first visible row, unless it is the current lead selection, in which case, the label is moved to the second visible row:
import java.awt.BorderLayout;
import java.awt.Point;
import java.util.Vector;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.ListSelectionModel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
public class TestTable {
protected void initUI() {
Vector<Vector<Object>> data = new Vector<Vector<Object>>();
Vector<String> colNames = new Vector<String>();
for (int i = 0; i < 5; i++) {
colNames.add("Col-" + (i + 1));
}
for (int i = 0; i < 200; i++) {
Vector<Object> row = new Vector<Object>();
for (int j = 0; j < 5; j++) {
row.add("Cell " + (i + 1) + "-" + (j + 1));
}
data.add(row);
}
table = new JTable(data, colNames);
someText = new JLabel();
someText.setOpaque(true);
table.add(someText);
table.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
table.getSelectionModel().addListSelectionListener(new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
int count = table.getSelectedRowCount();
someText.setText("You currently have selected " + count + " item" + (count > 1 ? "s" : ""));
layoutLabel();
}
});
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
scrollpane = new JScrollPane(table);
scrollpane.getViewport().addChangeListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent e) {
layoutLabel();
}
});
frame.add(scrollpane, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
private JLabel someText;
private JTable table;
private JScrollPane scrollpane;
private void layoutLabel() {
someText.setSize(someText.getPreferredSize());
Point location = scrollpane.getViewport().getViewRect().getLocation();
int leadSelectionIndex = table.getSelectionModel().getLeadSelectionIndex();
if (leadSelectionIndex > -1) {
if (table.rowAtPoint(location) == leadSelectionIndex) {
location.y += table.getRowHeight(leadSelectionIndex);
}
}
someText.setLocation(location);
}
public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException,
UnsupportedLookAndFeelException {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new TestTable().initUI();
}
});
}
}

you can to set Locations for ToolTip with the similair effect like as in MsExcell,
it is not a Tooltip as it is intended to be shown when user clicks into the table and selects cells and not by hovering over it.
you can to use JPopup / JWindow instead of ToolTip, for non_editable contens
JPopup / JWindow by default can't contains editable JComponent (JTextComponents)
for user input you can to use undecorated JDialod only

Yet another option is to implement a per-component glassPane (one of the many roles of JLayer for 1.7, JXLayer for 1.6) like shown below. Note that I didn't try to prettify the location (as #Guillaume did). Also, you'll have to modify the Rob's DragLayout a bit to guarantee that the box is shown inside the table area.
public static class ToolTipUI extends LayerUI<JTable> {
private JLayer<JTable> layer;
private JToolTip toolTip;
#Override
public void installUI(JComponent c) {
super.installUI(c);
this.layer = (JLayer) c;
installGlassPane();
installListeners();
}
private void installListeners() {
ListSelectionListener l = new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
if (e.getValueIsAdjusting()) return;
updateToolTip();
}
};
getTable().getColumnModel().getSelectionModel().addListSelectionListener(l);
getTable().getSelectionModel().addListSelectionListener(l);
}
private void updateToolTip() {
int[] selectedColumns = getTable().getColumnModel().getSelectedColumns();
int selectedRow = getTable().getSelectedRow();
if (selectedRow < 0 || selectedColumns.length == 0) {
setToolTipText("");
} else {
String text = "selected cells: ";
for (int i = 0; i < selectedColumns.length; i++) {
text += " " + selectedColumns[i];
}
setToolTipText(text);
}
}
private void setToolTipText(String string) {
toolTip.setTipText(string);
Rectangle cellBounds = getTable().getCellRect(getTable().getSelectedRow(), 0, false);
toolTip.setLocation(cellBounds.getLocation());
doLayout(layer);
}
#Override
public void doLayout(JLayer<? extends JTable> l) {
super.doLayout(l);
l.getGlassPane().doLayout();
}
private JTable getTable() {
return layer.getView();
}
private void installGlassPane() {
toolTip = ((JComponent) layer.getView()).createToolTip();
layer.getGlassPane().setBorder(BorderFactory.createLineBorder(Color.RED));
// DragLayout by Rob Camick http://tips4java.wordpress.com/2011/10/23/drag-layout/
layer.getGlassPane().setLayout(new DragLayout());
layer.getGlassPane().add(toolTip);
layer.getGlassPane().setVisible(true);
}
}
// usage:
JTable table = new JTable(new AncientSwingTeam());
JLayer layer = new JLayer<JTable>(table, new ToolTipUI());

doClick not releasing keys until loop ends

I'm making a piano application in Java. This is one of the functions,
public void playOnce(int time) {
play();
doClick(time);
stop();
}
public void play() {
channel[0].noteOn(note, 60);
}
public void stop() {
channel[0].noteOff(note);
}
I'll provide a minimal working example if necessary, but I wanted to make sure it's not an obvious issue. The problem is that playOnce is called in a while loop. playOnce is in a Key class, and each Key has a different note. In each iteration of the while loop, playOnce is called on a different key. Once all the keys have been played, it stops.
The doClick method correctly pressed the key, but it's not released until all the keys have been played. In fact, while the keys are being played, you can't do anything, even press the pause button. For this problem, I guess I could put the entire loop in a different thread, but I don't think that type of solution will allow the key to be released.
EDIT: Yea, I figured out I need a new thread to get other actions to work, but I still need a fix for doClick(). This might be more complicated than I thought so here's a working example,
Main.java
import java.awt.Container;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.text.DecimalFormat;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
import javax.swing.JSpinner;
import javax.swing.JTextArea;
import javax.swing.SpinnerNumberModel;
public class Main implements ActionListener {
final int WHITE_KEY_WIDTH, WHITE_KEY_HEIGHT, BLACK_KEY_WIDTH,
BLACK_KEY_HEIGHT;
final int WIDTH;
final JFileChooser fc;
{
WHITE_KEY_WIDTH = Key.WHITE_KEY_WIDTH;
BLACK_KEY_WIDTH = Key.BLACK_KEY_WIDTH;
WHITE_KEY_HEIGHT = Key.WHITE_KEY_HEIGHT;
BLACK_KEY_HEIGHT = Key.BLACK_KEY_HEIGHT;
WIDTH = 3 * (WHITE_KEY_WIDTH * 7) + WHITE_KEY_WIDTH;
fc = new JFileChooser();
}
public static Key keys[] = new Key[48];
private static int index = 0;
private String prevText = "";
JTextArea shabadEditor = null;
JSpinner tempoControl;
JFrame frame;
File curFile;
public static void main(String[] args) {
new Main();
}
public Main() {
frame = new JFrame();
JPanel mainPanel = new JPanel();
JPanel controlPanel = new JPanel();
JLayeredPane pianoPanel = new JLayeredPane();
mainPanel.setLayout(new GridBagLayout());
JButton playButton = new JButton("Play");
JButton pauseButton = new JButton("Pause");
playButton.addActionListener(this);
playButton.setActionCommand("play");
pauseButton.addActionListener(this);
pauseButton.setActionCommand("pause");
SpinnerNumberModel model = new SpinnerNumberModel(1, 0, 2, .1);
tempoControl = new JSpinner(model);
JSpinner.NumberEditor editor = (JSpinner.NumberEditor) tempoControl
.getEditor();
DecimalFormat format = editor.getFormat();
format.setMinimumFractionDigits(1);
Dimension d = tempoControl.getPreferredSize();
d.width = 40;
tempoControl.setPreferredSize(d);
GridBagConstraints c = new GridBagConstraints();
// Construct each top level component
controlPanel.add(playButton);
controlPanel.add(pauseButton);
controlPanel.add(tempoControl);
shabadEditor = new JTextArea(20, 78);
constructKeyboard(pianoPanel);
// Add the piano panel and shabad editor to the window
c.gridx = 0;
c.gridy = 0;
c.weightx = 1.0;
c.anchor = GridBagConstraints.NORTHWEST;
mainPanel.add(controlPanel, c);
c.gridx = 0;
c.gridy = 1;
c.weightx = 1.0;
// c.weighty = 1.0;
c.anchor = GridBagConstraints.NORTHWEST;
pianoPanel
.setPreferredSize(new Dimension(WIDTH - 18, WHITE_KEY_HEIGHT));
mainPanel.add(pianoPanel, c);
c.gridx = 0;
c.gridy = 2;
c.weightx = 1.0;
c.weighty = 1.0;
c.anchor = GridBagConstraints.NORTHWEST;
mainPanel.add(shabadEditor, c);
frame.add(mainPanel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(WIDTH, WHITE_KEY_HEIGHT * 3 + 30);
frame.setLocation(250, 60);
frame.setVisible(true);
}
void constructKeyboard(Container panel) {
int i = 0;
int j = 0;
for (int k = 0; k < 3; k++) {
addWhiteKey(panel, i++);
addBlackKey(panel, j++);
addWhiteKey(panel, i++);
addBlackKey(panel, j++);
addWhiteKey(panel, i++);
addWhiteKey(panel, i++);
j++;
addBlackKey(panel, j++);
addWhiteKey(panel, i++);
addBlackKey(panel, j++);
addWhiteKey(panel, i++);
addBlackKey(panel, j++);
j++;
addWhiteKey(panel, i++);
}
}
void addWhiteKey(Container panel, int i) {
WhiteKey b = new WhiteKey();
b.setLocation(i++ * WHITE_KEY_WIDTH, 0);
panel.add(b, 0, -1);
keys[index++] = b;
}
void addBlackKey(Container panel, int factor) {
BlackKey b = new BlackKey();
b.setLocation(WHITE_KEY_WIDTH - BLACK_KEY_WIDTH / 2 + factor
* WHITE_KEY_WIDTH, 0);
panel.add(b, 1, -1);
keys[index++] = b;
}
#Override
public void actionPerformed(ActionEvent arg0) {
String action = arg0.getActionCommand();
if (action.equals("play")) {
System.out.println("working");
for (int i = 0; i < 10; i++) {
keys[i].playOnce(500);
}
}
}
}
Key.java
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.sound.midi.MidiChannel;
import javax.sound.midi.MidiSystem;
import javax.sound.midi.MidiUnavailableException;
import javax.sound.midi.Synthesizer;
import javax.swing.JButton;
public class Key extends JButton implements MouseListener {
private static final long serialVersionUID = 1L;
public static final int WHITE_KEY_HEIGHT = 200;
public static final int WHITE_KEY_WIDTH = 40;
public static final int BLACK_KEY_WIDTH = 20;
public static final int BLACK_KEY_HEIGHT = 120;
private static int noteCount = 40;
public int note;
private static Synthesizer synth = null;
static {
try {
synth = MidiSystem.getSynthesizer();
synth.open();
} catch (MidiUnavailableException e) {
e.printStackTrace();
}
}
MidiChannel channel[];
public Key() {
note = noteCount++;
// Instrument[] instruments = synth.getAvailableInstruments();
// for (Instrument instrument : instruments) {
// System.out.println(instrument.getName());
// System.out.println(instrument.getPatch().getBank());
// System.out.println(instrument.getPatch().getProgram());
// }
channel = synth.getChannels();
channel[0].programChange(20);
addMouseListener(this);
}
public void playOnce(int time) {
play();
doClick(time);
stop();
}
public void play() {
channel[0].noteOn(note, 60);
}
public void stop() {
channel[0].noteOff(note);
}
#Override
public void mouseClicked(MouseEvent e) {
System.out.println(this.note);
}
#Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mousePressed(MouseEvent e) {
play();
}
#Override
public void mouseReleased(MouseEvent e) {
stop();
}
}
BlackKey.java
import java.awt.Color;
public class BlackKey extends Key {
private static final long serialVersionUID = 1L;
public BlackKey() {
super();
setBackground(Color.BLACK);
setSize(BLACK_KEY_WIDTH, BLACK_KEY_HEIGHT);
}
}
WhiteKey.java
import java.awt.Color;
public class WhiteKey extends Key {
private static final long serialVersionUID = 1L;
public WhiteKey() {
super();
setBackground(Color.WHITE);
setSize(WHITE_KEY_WIDTH, WHITE_KEY_HEIGHT);
}
}
EDIT: After doing a bit of work with threading, this is what I have
By putting the for loop in another thread, the keys are released at the right time:
#Override
public void actionPerformed(ActionEvent arg0) {
String action = arg0.getActionCommand();
if (action.equals("play")) {
System.out.println("working");
new Thread(new Runnable() {
public void run() {
for (int i = 0; i < 20; i++) {
keys[i].playOnce(100);
}
}
}).start();
}
}
}
The issue now is that the keyboard glitches. The keyboard is created using a layered pane, and for some reason when the keys are released the layers that are supposed to be on the bottom come to the top. When I hover my mouse over them, the glitch goes away. Any ideas?
EDIT2: I fixed the glitches. I simply had to add
try {
Thread.sleep(10);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
after doClick();

The problem with your approach is that you are blocking the event thread. This thread is responsible for user input, painting and window updates. My guess is now, that doClick's timeout gets checked inside the event thread (seems logical), so it won't get released until your actionPerformed method exits (and so the event thread can continue its event processing).
A solution to this problem would be (as you already mentioned) moving your for loop to another thread and call doClick using SwingUtilities.invokeLater.