Mega Code Archive
Coordinate Demo
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/*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* -Redistribution of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* -Redistribution in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
* REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
* INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
* OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
* EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
/* CoordinatesDemo.java is a 1.4 application that requires no other files. */
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.Point;
import java.awt.event.MouseEvent;
import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.event.MouseInputListener;
/*
* This displays a framed area. As the user moves the cursor over the area, a
* label displays the cursor's location. When the user clicks, the area displays
* a 7x7 dot at the click location.
*/
public class CoordinatesDemo {
private JLabel label;
private Point clickPoint, cursorPoint;
private void buildUI(Container container) {
container.setLayout(new BoxLayout(container, BoxLayout.PAGE_AXIS));
CoordinateArea coordinateArea = new CoordinateArea(this);
container.add(coordinateArea);
label = new JLabel();
resetLabel();
container.add(label);
//Align the left edges of the components.
coordinateArea.setAlignmentX(Component.LEFT_ALIGNMENT);
label.setAlignmentX(Component.LEFT_ALIGNMENT); //redundant
}
public void updateCursorLocation(int x, int y) {
if (x < 0 || y < 0) {
cursorPoint = null;
updateLabel();
return;
}
if (cursorPoint == null) {
cursorPoint = new Point();
}
cursorPoint.x = x;
cursorPoint.y = y;
updateLabel();
}
public void updateClickPoint(Point p) {
clickPoint = p;
updateLabel();
}
public void resetLabel() {
cursorPoint = null;
updateLabel();
}
protected void updateLabel() {
String text = "";
if ((clickPoint == null) && (cursorPoint == null)) {
text = "Click or move the cursor within the framed area.";
} else {
if (clickPoint != null) {
text += "The last click was at (" + clickPoint.x + ", "
+ clickPoint.y + "). ";
}
if (cursorPoint != null) {
text += "The cursor is at (" + cursorPoint.x + ", "
+ cursorPoint.y + "). ";
}
}
label.setText(text);
}
/**
* Create the GUI and show it. For thread safety, this method should be
* invoked from the event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
JFrame frame = new JFrame("CoordinatesDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Set up the content pane.
CoordinatesDemo controller = new CoordinatesDemo();
controller.buildUI(frame.getContentPane());
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
public static class CoordinateArea extends JComponent implements
MouseInputListener {
Point point = null;
CoordinatesDemo controller;
Dimension preferredSize = new Dimension(400, 75);
Color gridColor;
public CoordinateArea(CoordinatesDemo controller) {
this.controller = controller;
//Add a border of 5 pixels at the left and bottom,
//and 1 pixel at the top and right.
setBorder(BorderFactory.createMatteBorder(1, 5, 5, 1, Color.RED));
addMouseListener(this);
addMouseMotionListener(this);
setBackground(Color.WHITE);
setOpaque(true);
}
public Dimension getPreferredSize() {
return preferredSize;
}
protected void paintComponent(Graphics g) {
//Paint background if we're opaque.
if (isOpaque()) {
g.setColor(getBackground());
g.fillRect(0, 0, getWidth(), getHeight());
}
//Paint 20x20 grid.
g.setColor(Color.GRAY);
drawGrid(g, 20);
//If user has chosen a point, paint a small dot on top.
if (point != null) {
g.setColor(getForeground());
g.fillRect(point.x - 3, point.y - 3, 7, 7);
}
}
//Draws a 20x20 grid using the current color.
private void drawGrid(Graphics g, int gridSpace) {
Insets insets = getInsets();
int firstX = insets.left;
int firstY = insets.top;
int lastX = getWidth() - insets.right;
int lastY = getHeight() - insets.bottom;
//Draw vertical lines.
int x = firstX;
while (x < lastX) {
g.drawLine(x, firstY, x, lastY);
x += gridSpace;
}
//Draw horizontal lines.
int y = firstY;
while (y < lastY) {
g.drawLine(firstX, y, lastX, y);
y += gridSpace;
}
}
//Methods required by the MouseInputListener interface.
public void mouseClicked(MouseEvent e) {
int x = e.getX();
int y = e.getY();
if (point == null) {
point = new Point(x, y);
} else {
point.x = x;
point.y = y;
}
controller.updateClickPoint(point);
repaint();
}
public void mouseMoved(MouseEvent e) {
controller.updateCursorLocation(e.getX(), e.getY());
}
public void mouseExited(MouseEvent e) {
controller.resetLabel();
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
}
public void mouseDragged(MouseEvent e) {
}
}
}
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