package swingExamples;
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Line2D;
import java.awt.geom.Point2D;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.PlainDocument;
class ValidatedClockFrame extends JFrame
{
public ValidatedClockFrame()
{
setTitle("ValidatedClock");
setSize(300, 200);
setDefaultCloseOperation(EXIT_ON_CLOSE);
// Create main panel and add it to the content pane
JPanel mainPanel = new JPanel(new BorderLayout());
Container contentPane = getContentPane();
contentPane.add(mainPanel);
// Add the clock panel to the center of the main panel
mainPanel.add(m_clockPanel, BorderLayout.CENTER);
// Prepare a document listener
DocumentListener listener = new ClockFieldListener();
// Create the input panel containing text input fields,
// and connect the text input fields up with the listener
JPanel inputPanel = new JPanel();
inputPanel.add(new JLabel("Hours:"));
inputPanel.add(m_hourField);
m_hourField.getDocument().addDocumentListener(listener);
inputPanel.add(new JLabel("Minutes:"));
inputPanel.add(m_minuteField);
m_minuteField.getDocument().addDocumentListener(listener);
// Add the Tick button and hook it up
JButton tickButton = new JButton("Tick");
tickButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ev)
{
m_clockPanel.tick();
}
}
);
inputPanel.add(tickButton);
// Add the input panel to the south of the main panel
mainPanel.add(inputPanel, BorderLayout.SOUTH);
// Set the clock's initial state
setClock();
// Self-size the frame.
pack();
}
private void setClock()
{
if (m_hourField.isValid() && m_minuteField.isValid())
{
int hours = m_hourField.getValue();
int minutes = m_minuteField.getValue();
m_clockPanel.setTime(hours, minutes);
}
}
/// Private data ///
private ClockPanel m_clockPanel = new ClockPanel();
private IntTextField m_hourField = new IntTextField(12, 3);
private IntTextField m_minuteField = new IntTextField(00, 3);
/// Inner class ///
private class ClockFieldListener implements DocumentListener
{
public void insertUpdate(DocumentEvent event)
{
setClock();
}
public void removeUpdate(DocumentEvent event)
{
setClock();
}
public void changedUpdate(DocumentEvent event)
{}
}
}
class ClockPanel extends JPanel
{
public ClockPanel()
{
// Set the preferred size of the panel
// for layout purposes (pack)
setPreferredSize(
new Dimension(2 * RADIUS + 1 + 10, // Insets
2 * RADIUS + 1 + 10) // Insets
);
}
public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
// Create a BasicStroke for drawing outlines
BasicStroke stroke =
new BasicStroke(3.0F,
BasicStroke.CAP_ROUND,
BasicStroke.JOIN_ROUND);
g2.setStroke(stroke);
// Draw the outline of the clock
Ellipse2D circle =
new Ellipse2D.Double(INSET, INSET,
2 * RADIUS,
2 * RADIUS);
g2.setPaint(Color.GRAY);
g2.draw(circle);
stroke = new BasicStroke(8.0F,
BasicStroke.CAP_ROUND,
BasicStroke.JOIN_ROUND);
g2.setStroke(stroke);
// Draw the hour hand
double hourDegrees =
90 - 360 * m_minutes / (12 * 60);
double hourAngle = Math.toRadians(hourDegrees);
g2.setPaint(Color.BLUE);
drawHand(g2, hourAngle, HOUR_HAND_LENGTH);
// Draw the minute hand
double minuteDegrees =
90 - 360 * m_minutes / 60;
double minuteAngle = Math.toRadians(minuteDegrees);
g2.setPaint(Color.BLUE);
drawHand(g2, minuteAngle, MINUTE_HAND_LENGTH);
// Draw the axle
Ellipse2D axle =
new Ellipse2D.Double(INSET + RADIUS - AXLE_RADIUS,
INSET + RADIUS - AXLE_RADIUS,
2 * AXLE_RADIUS,
2 * AXLE_RADIUS);
g2.setPaint(Color.RED);
g2.fill(axle);
}
private void drawHand(Graphics2D g2,
double angle, double handLength)
{
Point2D end =
new Point2D.Double(INSET + RADIUS +
handLength * Math.cos(angle),
INSET + RADIUS -
handLength * Math.sin(angle));
Point2D center =
new Point2D.Double(INSET + RADIUS, INSET + RADIUS);
g2.draw(new Line2D.Double(center, end));
}
public void setTime(int hours, int minutes)
{
m_minutes = hours * 60 + minutes;
repaint();
}
public void tick()
{
m_minutes++;
repaint();
}
////// Private data //////
private static final int INSET = 5;
private static final int RADIUS = 100;
private static final double HOUR_HAND_LENGTH =
0.6 * RADIUS;
private static final double MINUTE_HAND_LENGTH =
0.9 * RADIUS;
private static final double AXLE_RADIUS = 10;
private double m_minutes = 0;
}
class IntTextField extends JTextField
{
public IntTextField(int defaultValue, int columns)
{
super("" + defaultValue, columns);
}
public boolean isValid()
{
boolean ret = false;
try
{
Integer.parseInt(getText());
ret = true;
}
catch (NumberFormatException ex)
{
// Do nothing
}
return ret;
}
public int getValue()
{
int value = 0;
try
{
value = Integer.parseInt(getText());
}
catch (NumberFormatException ex)
{
}
return value;
}
protected Document createDefaultModel()
{
return new IntTextDocument();
}
}
class IntTextDocument extends PlainDocument
{
public void insertString(int offset, String text,
AttributeSet attr) throws BadLocationException
{
if (text != null)
{
String oldString = getText(0, getLength());
String newString = oldString.substring(0, offset)
+ text + oldString.substring(offset);
try
{
Integer.parseInt(newString + "0");
// For the case of "" or "-", etc.
super.insertString(offset, text, attr);
}
catch (NumberFormatException ex)
{
}
}
}
}
public class ValidatedClock
{
public static void main(String[] args)
{
ValidatedClockFrame frame = new ValidatedClockFrame();
frame.setVisible(true);
}
}
|
