Computer Science 120
Introduction to Programming
Spring 2012, Siena College
Drag2Shirts Demo
A working demo of Drag2Shirts will appear below. Click inside the applet to interact with it.
Drag2Shirts BlueJ Project
Click here to download a BlueJ project for Drag2Shirts.
Drag2Shirts Source Code
The Java source code for Drag2Shirts is below. Click on a file name to download it.
import objectdraw.*;
import java.awt.*;
/*
* Example Drag2Shirts
*
* Drag a shirt around window, given choice
* of red shirt or blue shirt.
*
* Jim Teresco, Siena College, CSIS 120, Spring 2011
* Based on example from Williams College CSCI 134
*
* $Id: Drag2Shirts.java 1577 2011-03-28 02:10:20Z terescoj $
*/
public class Drag2Shirts extends WindowController {
// starting location of t-shirt
private static final int ITEM_LEFT = 75;
private static final int ITEM_TOP = 50;
private static final int SND_OFFSET = 150;
// T-shirts on the screen
private TShirt redShirt, blueShirt;
// The piece of laundry to be moved.
private TShirt selectedShirt;
// Previously noted position of mouse cursor
private Location lastPoint;
// Whether user is actually dragging a shirt
private boolean dragging;
// display the shirts
public void begin() {
redShirt = new TShirt(ITEM_LEFT, ITEM_TOP, canvas);
redShirt.setColor(Color.red);
blueShirt = new TShirt(ITEM_LEFT + SND_OFFSET, ITEM_TOP, canvas);
blueShirt.setColor(Color.blue);
selectedShirt = blueShirt; // blue shirt on top at start
}
// Whenever mouse is depressed, note its location
// and which (if any) shirt the mouse is on.
public void onMousePress(Location point) {
lastPoint = point;
// test the selected shirt (which is on top) first.
if (selectedShirt.contains(point)) {
dragging = true;
} else if (blueShirt.contains(point)) {
selectedShirt = blueShirt;
dragging = true;
selectedShirt.sendToFront();
} else if (redShirt.contains(point)) {
selectedShirt = redShirt;
dragging = true;
selectedShirt.sendToFront();
} else {
dragging = false;
}
}
// If mouse is dragged, move the selected shirt with it
// If didn't press mouse on a shirt, do nothing
public void onMouseDrag(Location point) {
if (dragging) {
selectedShirt.move(point.getX() - lastPoint.getX(),
point.getY() - lastPoint.getY());
lastPoint = point;
}
}
// move both shirts back to starting positions when mouse leaves window
public void onMouseExit(Location point) {
redShirt.reset();
blueShirt.reset();
dragging = false;
}
}
import objectdraw.*;
import java.awt.*;
/*
* Example Drag2Shirts
*
* A class that defines a graphical type that looks a bit
* like a t-shirt.
*
* Jim Teresco, Siena College, CSIS 120, Spring 2011
* Based on example from Williams College CSCI 134
*
* $Id: TShirt.java 1541 2011-02-15 21:09:53Z terescoj $
*/
public class TShirt {
// constant dimensions
private static final int WIDTH = 150;
private static final int HEIGHT = 175;
private static final int BODY_WIDTH = 100;
private static final int NECK_HEIGHT = 20;
private static final int SLEEVE_OFFSET = NECK_HEIGHT/2;
private static final int NECK_WIDTH = 75;
private static final int SLEEVE_HEIGHT = 40;
private static final int BODY_HEIGHT = HEIGHT - SLEEVE_HEIGHT;
private static final int SLEEVE_LENGTH = (WIDTH-BODY_WIDTH)/2;
// instance variables for shirt components
private FilledRect body;
private FramedRect bodyFrame;
private FilledRect sleeves;
private FramedRect sleeveFrame;
private FilledOval neck;
private FramedOval neckFrame;
// remember the initial position of the tshirt
private double startX, startY;
/*
* Create a new T-shirt with its upper left corner at (x,y) and with
* a width of size.
*/
public TShirt(double x, double y, DrawingCanvas canvas) {
bodyFrame = new FramedRect(x+SLEEVE_LENGTH,
y+SLEEVE_HEIGHT, BODY_WIDTH, BODY_HEIGHT, canvas);
sleeves = new FilledRect(x, y+SLEEVE_OFFSET,
WIDTH, SLEEVE_HEIGHT, canvas);
sleeves.setColor(Color.white);
sleeveFrame = new FramedRect(x, y+SLEEVE_OFFSET,
WIDTH, SLEEVE_HEIGHT, canvas);
body = new FilledRect(x+SLEEVE_LENGTH+1,
y+SLEEVE_HEIGHT, BODY_WIDTH-2, BODY_HEIGHT-1, canvas);
body.setColor(Color.white);
neck = new FilledOval(x + (WIDTH-NECK_WIDTH)/2,
y, NECK_WIDTH, NECK_HEIGHT, canvas);
neck.setColor(Color.white);
neckFrame = new FramedOval(x + (WIDTH-NECK_WIDTH)/2,
y, NECK_WIDTH, NECK_HEIGHT, canvas);
// remember initial location
startX = x;
startY = y;
}
/*
* Move the t-shirt by specified offsets.
*/
public void move(double xOffset, double yOffset) {
bodyFrame.move(xOffset,yOffset);
sleeves.move(xOffset,yOffset);
sleeveFrame.move(xOffset,yOffset);
body.move(xOffset,yOffset);
neck.move(xOffset,yOffset);
neckFrame.move(xOffset,yOffset);
}
/*
* Returns true if the t-shirt contains the point;
* false otherwise
*/
public boolean contains(Location pt) {
return bodyFrame.contains(pt) ||
sleeveFrame.contains(pt) ||
neckFrame.contains(pt);
}
/*
* Change color of t-shirt to newColor.
*/
public void setColor(Color newColor) {
body.setColor(newColor);
sleeves.setColor(newColor);
neck.setColor(newColor);
}
/*
* Put t-shirt in front of other objects on canvas.
*
* Note that this must be done in a particular order to ensure
* that the t-shirt appears as intended (appropriate parts
* obscured behind others). We use the same order in which
* we originally constructed the t-shirt.
*/
public void sendToFront() {
bodyFrame.sendToFront();
sleeves.sendToFront();
sleeveFrame.sendToFront();
body.sendToFront();
neck.sendToFront();
neckFrame.sendToFront();
}
/*c
* Move the t-shirt to a new upper-left coordinate position.
*/
public void moveTo(double x, double y) {
double dx, dy;
dx = x - sleeves.getX();
dy = y - neck.getY();
this.move(dx, dy);
}
/*
* Move t-shirt back to starting position.
*/
public void reset() {
this.moveTo(startX, startY);
}
}