Displaying a timeline on a panel

Question

Hi everyone!!
I am trying to develop a project management tool, so I need to know the best way of implementing a timeline (in months) to display on a JPanel. Basically, when the user selects a start date and duration of the project, I need a timeline to appear depending on what the user has selected from the combo box. The timeline needs to start from the start date and continue for x amount of months (where x is the duration). At the moment I have used loads of switch statements, but there must be a much better and efficient way of implementing this. If anyone can help me with this then it will be most appreciated. My code is provided below which can be complied and run from the "NewChartTest" class file. Thanks.
* NewChartTest.java
* 23/11/02 (Date start)
* This class is for test purposes for
* the "New Chart" wizard
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
public class NewChartTest extends JPanel
private JButton newButton;
public JFrame wizardFrame;
static NewChartTest instance;     
public NewChartTest()
     instance = this;
// create new button
newButton = new JButton("New Chart");
// create tooltip for every button
newButton.setToolTipText("New Chart");
// add our button to the JPanel
add(newButton);
// construct button action
NewButtonListener listener1 = new NewButtonListener();
// Add action listener to button
newButton.addActionListener(listener1);
private class NewButtonListener implements ActionListener
public void actionPerformed(ActionEvent evt)
wizardFrame = new JFrame("New Chart Wizard*");
NewWizardPanel wizardPanel = new NewWizardPanel();
wizardFrame.getContentPane().add(wizardPanel);
wizardFrame.setSize(410, 280);
wizardFrame.setVisible(true);
// Main entry point into the ToolBarPanel class
public static void main(String[] args)
// Create a frame to hold us and set its title
JFrame frame = new JFrame("New Chart Test");
// Set frame to close after user request
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Add our tab panel to the frame
NewChartTest nct = new NewChartTest();
frame.getContentPane().add(nct, BorderLayout.CENTER);
// Resize the frame
frame.setSize(680, 480);
// Make the windows visible
frame.setVisible(true);
* NewWizardPanel.java
* 23/11/02 (Date start)
* This class is for test purposes for
* the "New Chart" wizard
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
public class NewWizardPanel extends JPanel
private JLabel projectNameLabel;
private JLabel maxCharacterLabel;
private JLabel durationLabel;
private JLabel monthLabel;
private JLabel startDate;
private JLabel forwardDash;
private JLabel forwardDash1;
private JLabel dateFormatLabel;
public JTextField projectName;
private JComboBox projectDay;
private JComboBox projectMonth;
private JComboBox projectYear;
private JComboBox projectDuration;
public String daySelect;
public String monthSelect;
public String yearSelect;
public String durationSelect;
private JButton okButton;
private JButton cancelButton;
private JFrame wizardFrame;
private JFrame drawChart;
static NewWizardPanel instance1;
public NewWizardPanel()
instance1 = this;
// create additional panels to hold objects
JPanel topPanel = new JPanel();
JPanel middlePanel = new JPanel();
JPanel lowerPanel = new JPanel();
JPanel buttonPanel = new JPanel();
// Create a border around the "toppanel"
Border etched = BorderFactory.createBevelBorder(BevelBorder.RAISED, Color.black, Color.blue);
Border titled = BorderFactory.createTitledBorder(etched, "Please provide a title to your project");
topPanel.setBorder(titled);
// Create a border around the "middlepanel"
Border etched1 = BorderFactory.createBevelBorder(BevelBorder.RAISED, Color.black, Color.blue);
Border titled1 = BorderFactory.createTitledBorder(etched1, "Please enter the start date of your project");
middlePanel.setBorder(titled1);
// Create a border around the "lowerpanel"
Border etched2 = BorderFactory.createBevelBorder(BevelBorder.RAISED, Color.black, Color.blue);
Border titled2 = BorderFactory.createTitledBorder(etched2, "Please select the duration of your project");
lowerPanel.setBorder(titled2);
// initialise label objects
projectNameLabel = new JLabel("Project Name", JLabel.LEFT);
maxCharacterLabel = new JLabel("(Max 20 Chars)");
durationLabel = new JLabel("Duration (in months)", JLabel.LEFT);
monthLabel = new JLabel("(1 - 12 months)");
startDate = new JLabel("Project Start Date", JLabel.LEFT);
forwardDash = new JLabel("/");
forwardDash1 = new JLabel("/ 20");
dateFormatLabel = new JLabel("(e.g. 31/12/02)");
projectName = new JTextField(20);
projectName.setColumns(15);
topPanel.validate();
String[] theDay = {"01", "02", "03", "04", "05", "06", "07", "08", "09", "10", "11", "12", "13", "14", "15", "16",
"17", "18", "19", "20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "30", "31"};
projectDay = new JComboBox(theDay);
projectDay.setEditable(false);
String[] theMonth = {"01", "02", "03", "04", "05", "06", "07", "08", "09", "10", "11", "12"};
projectMonth = new JComboBox(theMonth);
projectMonth.setEditable(false);
String[] theYear = {"01", "02", "03", "04", "05", "06", "07", "08", "09", "10", "11", "12"};
projectYear= new JComboBox(theYear);
projectYear.setEditable(false);
String[] theDuration = {"1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12"};
projectDuration = new JComboBox(theDuration);
projectDuration.setEditable(false);
// initialise buttons
okButton = new JButton("Ok", new ImageIcon("D:/My Uni Work/Final Year Project/Test/ok.gif"));
cancelButton = new JButton("Cancel", new ImageIcon("D:/My Uni Work/Final Year Project/Test/cancel.gif"));
// set tooltips for buttons
okButton.setToolTipText("Ok");
cancelButton.setToolTipText("Cancel");
// add objects to panels
topPanel.add(projectNameLabel);
topPanel.add(projectName);
topPanel.add(maxCharacterLabel);
middlePanel.add(startDate);
middlePanel.add(projectDay);
middlePanel.add(forwardDash);
middlePanel.add(projectMonth);
middlePanel.add(forwardDash1);
middlePanel.add(projectYear);
middlePanel.add(dateFormatLabel);
lowerPanel.add(durationLabel);
lowerPanel.add(projectDuration);
lowerPanel.add(monthLabel);
buttonPanel.add(okButton);
buttonPanel.add(cancelButton);
// create instance of cancelButtonListener
CancelButtonListener cancelListen = new CancelButtonListener();
// create instance of okButtonListner
OkButtonListener okListen = new OkButtonListener();
// add actionListener for the cancel/ok button
cancelButton.addActionListener(cancelListen);
okButton.addActionListener(okListen);
// use Box layout to arrange panels
Box hbox2 = Box.createHorizontalBox();
hbox2.add(topPanel);
Box hbox3 = Box.createHorizontalBox();
hbox3.add(middlePanel);
Box hbox4 = Box.createHorizontalBox();
hbox4.add(lowerPanel);
Box hbox5 = Box.createHorizontalBox();
hbox5.add(buttonPanel);
Box vbox = Box.createVerticalBox();
vbox.add(hbox2);
vbox.add(Box.createGlue());
vbox.add(hbox3);
vbox.add(Box.createGlue());
vbox.add(hbox4);
vbox.add(Box.createGlue());
vbox.add(hbox5);
this.add(vbox, BorderLayout.NORTH);
private class CancelButtonListener implements ActionListener
public void actionPerformed(ActionEvent event)
Object source = event.getSource();
if(source == cancelButton)
NewChartTest.instance.wizardFrame.setVisible(false);
private class OkButtonListener implements ActionListener
public void actionPerformed(ActionEvent event)
String nameText = projectName.getText().trim();
int textSize = nameText.length();
daySelect = (String)projectDay.getSelectedItem();
monthSelect = (String)projectMonth.getSelectedItem();
yearSelect = (String)projectYear.getSelectedItem();
durationSelect = (String)projectDuration.getSelectedItem();
if(textSize > 20)
//display a JOptionPane
JOptionPane.showMessageDialog(NewWizardPanel.instance1, "You have entered a title that is greater than 20 characters. Please change this.",
"Text too Long", JOptionPane.ERROR_MESSAGE);
else if(textSize == 0)
//display a JOptionPane
JOptionPane.showMessageDialog(NewWizardPanel.instance1, "You have not entered a project name. Please do so (Maximum 20 Characters).",
"No Project Name Entered", JOptionPane.ERROR_MESSAGE);
else if(daySelect == "30" && monthSelect == "02" || daySelect == "31" && monthSelect == "02" || daySelect == "31" && monthSelect == "04" ||
daySelect == "31" && monthSelect == "06" || daySelect == "31" && monthSelect == "09" || daySelect == "31" && monthSelect == "11")
JOptionPane.showMessageDialog(NewWizardPanel.instance1, "You have selected an invalid date. Please re-check that the date is valid.",
"Invalid Date Selected", JOptionPane.ERROR_MESSAGE);
else
NewChartTest.instance.wizardFrame.setVisible(false);
drawChart = new JFrame("Milestone Chart Panel");
DrawPanel drawingChart = new DrawPanel();
drawChart.getContentPane().add(drawingChart);
drawChart.setSize(1000, 510);
drawChart.setVisible(true);
* DrawPanel.java
* 27/11/02 (Date start)
* This class is for test purposes for
* the "New Chart" wizard
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.io.*;
public class DrawPanel extends JPanel
private JLabel aName;
private JLabel date;
private JLabel day;
private JLabel forwardSlash1;
private JLabel month;
private JLabel forwardSlash2;
private JLabel year;
private JLabel empty;
private JLabel startingMonth;
private JPanel nameHolder;
private JPanel dateHolder;
private JPanel emptyPanel;
private JPanel calendarPanel;
private JPanel timelinePanel;
private JPanel zoomInButtonPanel;
private JPanel zoomOutButtonPanel;
private JTextField projectName;
private String daySelect;
private JButton zoomIn;
private JButton zoomOut;
private JScrollPane timeLineScroll;
private String theDuration;
private String startMonth;
private String monthStart;
private String[] theMonths = {"January", "February", "March", "April", "May", "June", "July", "August",
"September", "October", "November", "December"};
//private String requiredMonths;
public DrawPanel()
nameHolder = new JPanel();
dateHolder = new JPanel();
emptyPanel = new JPanel();
calendarPanel = new JPanel();
calendarPanel.setBackground(Color.white);
timelinePanel = new timeLinePanel();
timelinePanel.setBackground(Color.white);
zoomInButtonPanel = new JPanel();
zoomInButtonPanel.setBackground(Color.black);
zoomOutButtonPanel = new JPanel();
zoomOutButtonPanel.setBackground(Color.black);
String name = NewWizardPanel.instance1.projectName.getText().trim();
aName = new JLabel(name, JLabel.CENTER);
date = new JLabel("Date Start:");
String dayStart = NewWizardPanel.instance1.daySelect;
day = new JLabel(dayStart);
forwardSlash1 = new JLabel("/");
monthStart = NewWizardPanel.instance1.monthSelect;
month = new JLabel(monthStart);
forwardSlash2 = new JLabel("/");
String yearStart = NewWizardPanel.instance1.yearSelect;
year = new JLabel(yearStart);
empty = new JLabel(" ");
// initialise buttons required for panel
zoomIn = new JButton(new ImageIcon("D:/My Uni Work/Final Year Project/Test/zoomIn.gif"));
zoomOut = new JButton(new ImageIcon("D:/My Uni Work/Final Year Project/Test/zoomOut.gif"));
// set the tool tips for the buttons
zoomIn.setToolTipText("Zoom In");
zoomOut.setToolTipText("Zoom Out");
theDuration = NewWizardPanel.instance1.durationSelect;
drawTimeLine(monthStart, theDuration);
nameHolder.add(aName);
dateHolder.add(date);
dateHolder.add(day);
dateHolder.add(forwardSlash1);
dateHolder.add(month);
dateHolder.add(forwardSlash2);
dateHolder.add(year);
emptyPanel.add(empty);
zoomInButtonPanel.add(zoomIn);
zoomOutButtonPanel.add(zoomOut);
dateHolder.setPreferredSize(new Dimension(200, 30));
emptyPanel.setPreferredSize(new Dimension(750, 30));
calendarPanel.setPreferredSize(new Dimension(950, 30));
timelinePanel.setPreferredSize(new Dimension(950, 300));
zoomInButtonPanel.setPreferredSize(new Dimension(100, 50));
zoomOutButtonPanel.setPreferredSize(new Dimension(100, 50));
// use Box layout to arrange panels
Box hbox1 = Box.createHorizontalBox();
hbox1.add(nameHolder);
Box hbox2 = Box.createHorizontalBox();
hbox2.add(dateHolder);
hbox2.add(emptyPanel);
Box hbox3 = Box.createHorizontalBox();
hbox3.add(calendarPanel);
Box hbox4 = Box.createHorizontalBox();
hbox4.add(timelinePanel);
Box hbox5 = Box.createHorizontalBox();
hbox5.add(zoomOutButtonPanel);
hbox5.add(zoomInButtonPanel);
Box vbox = Box.createVerticalBox();
vbox.add(hbox1);
vbox.add(Box.createGlue());
vbox.add(hbox2);
vbox.add(Box.createGlue());
vbox.add(hbox3);
vbox.add(Box.createGlue());
vbox.add(hbox4);
vbox.add(Box.createGlue());
vbox.add(hbox5);
this.add(vbox, BorderLayout.NORTH);
public void drawTimeLine(String aStartMonth, String aDuration)
if(monthStart == "01")
startMonth = theMonths[0];
System.out.println(theDuration);
int duration = Integer.parseInt(theDuration);
switch(duration)
case 1:
JLabel months = new JLabel(startMonth);
calendarPanel.add(months);
break;
case 2:
JLabel months1 = new JLabel(startMonth + " " + theMonths[1]);
calendarPanel.add(months1);
break;
case 3:
JLabel months2 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2]);
calendarPanel.add(months2);
break;
case 4:
JLabel months3 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3]);
calendarPanel.add(months3);
break;
case 5:
JLabel months4 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]);
calendarPanel.add(months4);
break;
case 6:
JLabel months5 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]
+ " " + theMonths[5]);
calendarPanel.add(months5);
break;
case 7:
JLabel months6 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]
+ " " + theMonths[5] + " " + theMonths[6]);
calendarPanel.add(months6);
break;
case 8:
JLabel months7 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]
+ " " + theMonths[5] + " " + theMonths[6] + " " + theMonths[7]);
calendarPanel.add(months7);
break;
case 9:
JLabel months8 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]
+ " " + theMonths[5] + " " + theMonths[6] + " " + theMonths[7] + " " + theMonths[8]);
calendarPanel.add(months8);
break;
case 10:
JLabel months9 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]
+ " " + theMonths[5] + " " + theMonths[6] + " " + theMonths[7] + " " + theMonths[8] + " " + theMonths[9]);
calendarPanel.add(months9);
break;
case 11:
JLabel months10 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]
+ " " + theMonths[5] + " " + theMonths[6] + " " + theMonths[7] + " " + theMonths[8] + " " + theMonths[9] + " " + theMonths[10]);
calendarPanel.add(months10);
break;
case 12:
JLabel months11 = new JLabel(startMonth + " " + theMonths[1] + " " + theMonths[2] + " " + theMonths[3] + " " + theMonths[4]
+ " " + theMonths[5] + " " + theMonths[6] + " " + theMonths[7] + " " + theMonths[8] + " " + theMonths[9] + " " + theMonths[10] + " " + theMonths[11]);
calendarPanel.add(months11);
break;
} // + loads more "if else" and "switch" statements - there must be an easier and more effiecient way!!!!
class timeLinePanel extends JPanel
private int x1 = 50;
private int x2 = 50;
private int y1 = 7;
private int y2 = 13;
public void paintComponent(Graphics g)
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
Line2D timeLine = new Line2D.Double(50, 10, 900, 10);
g2.draw(timeLine);
g2.setColor(Color.blue);
Line2D separatorStart = new Line2D.Double(50, 7, 50, 13);
g2.draw(separatorStart);
Line2D separatorEnd = new Line2D.Double(900, 7, 900, 13);
g2.draw(separatorEnd);
Line2D Separator1 = new Line2D.Double(x1 + 100 , y1, x2 + 100, y2);
g2.draw(Separator1);
Line2D separator2 = new Line2D.Double(x1 + 200, y1, x2 + 200, y2);
g2.draw(separator2);
Line2D separator3 = new Line2D.Double(x1 + 300, y1, x2 + 300, y2);
g2.draw(separator3);
Line2D separator4 = new Line2D.Double(x1 + 400, y1, x2 + 400, y2);
g2.draw(separator4);
Line2D separator5 = new Line2D.Double(x1 + 500, y1, x2 + 500, y2);
g2.draw(separator5);
Line2D separator6 = new Line2D.Double(x1 + 600, y1, x2 + 600, y2);
g2.draw(separator6);
Line2D separator7 = new Line2D.Double(x1 + 700, y1, x2 + 700, y2);
g2.draw(separator7);
Line2D separator8 = new Line2D.Double(x1 + 800, y1, x2 + 800, y2);
g2.draw(separator8);
//Line2D separator9 = new Line2D.Double(x1 + 900, y1, x2 + 900, y2);
//g2.draw(separator9);
g2.setColor(Color.lightGray);
Line2D dividerLine = new Line2D.Double(150, 14, 150, 300);
g2.draw(dividerLine);
Line2D dividerLine1 = new Line2D.Double(250, 14, 250, 300);
g2.draw(dividerLine1);
Line2D dividerLine2 = new Line2D.Double(350, 14, 350, 300);
g2.draw(dividerLine2);
Line2D dividerLine3 = new Line2D.Double(450, 14, 450, 300);
g2.draw(dividerLine3);
Line2D dividerLine4 = new Line2D.Double(550, 14, 550, 300);
g2.draw(dividerLine4);
Line2D dividerLine5 = new Line2D.Double(650, 14, 650, 300);
g2.draw(dividerLine5);
Line2D dividerLine6 = new Line2D.Double(750, 14, 750, 300);
g2.draw(dividerLine6);
Line2D dividerLine7 = new Line2D.Double(850, 14, 850, 300);
g2.draw(dividerLine7);

Answer 1

Haven't looked at all your code by can't you use a loop?
int index = comboBox.getSelectedIndex();
StringBuffer buf = new StringBuffer("Start Month ");
JLabel label = new JLabel();
for (int counter = 0; counter < index; ++ counter)
buf.append(theMonths[counter] + " ");
label.setText(buf.toString());