/*
* @(#)BufferedShapeMover.java 1.2 99/07/26
*
* Copyright 1997, 1998, 1999 Sun Microsystems, Inc. All Rights
* Reserved.
*
* Sun grants you ("Licensee") a non-exclusive, royalty free,
* license to use, modify and redistribute this software in source and
* binary code form, provided that i) this copyright notice and license
* appear on all copies of the software; and ii) Licensee does not utilize
* the software in a manner which is disparaging to Sun.
*
* 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
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY
* LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THE 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 SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* This software is not designed or intended for use in on-line
* control of aircraft, air traffic, aircraft navigation or aircraft
* communications; or in the design, construction, operation or
* maintenance of any nuclear facility. Licensee represents and warrants
* that it will not use or redistribute the Software for such purposes.
*/
import java.awt.*;
import java.awt.event.*;
import java.applet.Applet;
import java.awt.image.*;
public class BufferedShapeMover extends Applet{
static protected Label label;
public void init(){
//Initialize the layout.
setLayout(new BorderLayout());
add(new BSMCanvas());
label = new Label("Drag rectangle around within the area");
add("South", label);
}
public static void main(String s[]) {
Frame f = new Frame("BufferedShapeMover");
f.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {System.exit(0);}
});
Applet applet = new BufferedShapeMover();
f.add("Center", applet);
applet.init();
f.pack();
f.setSize(new Dimension(550,250));
f.show();
}
}
class BSMCanvas extends Canvas implements MouseListener, MouseMotionListener{
Rectangle rect = new Rectangle(0, 0, 100, 50);
BufferedImage bi;
Graphics2D big;
// Holds the coordinates of the user's last mousePressed event.
int last_x, last_y;
boolean firstTime = true;
TexturePaint fillPolka, strokePolka;
Rectangle area;
// True if the user pressed, dragged or released the mouse outside of the rectangle; false otherwise.
boolean pressOut = false;
public BSMCanvas(){
setBackground(Color.white);
addMouseMotionListener(this);
addMouseListener(this);
// Creates the fill texture paint pattern.
bi = new BufferedImage(5, 5, BufferedImage.TYPE_INT_RGB);
big = bi.createGraphics();
big.setColor(Color.pink);
big.fillRect(0, 0, 7, 7);
big.setColor(Color.cyan);
big.fillOval(0, 0, 3, 3);
Rectangle r = new Rectangle(0,0,5,5);
fillPolka = new TexturePaint(bi, r);
big.dispose();
//Creates the stroke texture paint pattern.
bi = new BufferedImage(5, 5, BufferedImage.TYPE_INT_RGB);
big = bi.createGraphics();
big.setColor(Color.cyan);
big.fillRect(0, 0, 7, 7);
big.setColor(Color.pink);
big.fillOval(0, 0, 3, 3);
r = new Rectangle(0,0,5,5);
strokePolka = new TexturePaint(bi, r);
big.dispose();
}
// Handles the event of the user pressing down the mouse button.
public void mousePressed(MouseEvent e){
last_x = rect.x - e.getX();
last_y = rect.y - e.getY();
// Checks whether or not the cursor is inside of the rectangle while the user is pressing themouse.
if(rect.contains(e.getX(), e.getY())){
updateLocation(e);
} else {
BufferedShapeMover.label.setText("First position the cursor on the rectangle and then drag.");
pressOut = true;
}
}
// Handles the event of a user dragging the mouse while holding down the mouse button.
public void mouseDragged(MouseEvent e){
if(!pressOut){
updateLocation(e);
} else {
BufferedShapeMover.label.setText("First position the cursor on the rectangle and then drag.");
}
}
// Handles the event of a user releasing the mouse button.
public void mouseReleased(MouseEvent e){
// Checks whether or not the cursor is inside of the rectangle when the user releases the
// mouse button.
if(rect.contains(e.getX(), e.getY())){
updateLocation(e);
} else {
BufferedShapeMover.label.setText("First position the cursor on the rectangle and then drag.");
pressOut = false;
}
}
// This method required by MouseListener.
public void mouseMoved(MouseEvent e){}
// These methods are required by MouseMotionListener.
public void mouseClicked(MouseEvent e){}
public void mouseExited(MouseEvent e){}
public void mouseEntered(MouseEvent e){}
public void updateLocation(MouseEvent e){
rect.setLocation(last_x + e.getX(), last_y + e.getY());
/*
* Updates the label to reflect the location of the
* current rectangle
* if checkRect returns true; otherwise, returns error message.
*/
if (checkRect()) {
BufferedShapeMover.label.setText("Rectangle located at " +
rect.getX() + ", " +
rect.getY());
} else {
BufferedShapeMover.label.setText("Please don't try to "+
" drag outside the area.");
}
repaint();
}
public void paint(Graphics g){
update(g);
}
public void update(Graphics g){
Graphics2D g2 = (Graphics2D)g;
if(firstTime){
Dimension dim = getSize();
int w = dim.width;
int h = dim.height;
area = new Rectangle(dim);
bi = (BufferedImage)createImage(w, h);
big = bi.createGraphics();
rect.setLocation(w/2-50, h/2-25);
big.setStroke(new BasicStroke(8.0f));
firstTime = false;
}
// Clears the rectangle that was previously drawn.
big.setColor(Color.white);
big.clearRect(0, 0, area.width, area.height);
// Draws and fills the newly positioned rectangle to the buffer.
big.setPaint(strokePolka);
big.draw(rect);
big.setPaint(fillPolka);
big.fill(rect);
// Draws the buffered image to the screen.
g2.drawImage(bi, 0, 0, this);
}
/*
* Checks if the rectangle is contained within the applet window. If the rectangle
* is not contained withing the applet window, it is redrawn so that it is adjacent
* to the edge of the window and just inside the window.
*/
boolean checkRect(){
if (area == null) {
return false;
}
if(area.contains(rect.x, rect.y, 100, 50)){
return true;
}
int new_x = rect.x;
int new_y = rect.y;
if((rect.x+100)>area.width){
new_x = area.width-99;
}
if(rect.x < 0){
new_x = -1;
}
if((rect.y+50)>area.height){
new_y = area.height-49;
}
if(rect.y < 0){
new_y = -1;
}
rect.setLocation(new_x, new_y);
return false;
}
}
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