Computer Science 120
Introduction to Programming

Spring 2012, Siena College

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Drag10ShirtsNicer Demo

A working demo of Drag10ShirtsNicer will appear below. Click inside the applet to interact with it.

Drag10ShirtsNicer BlueJ Project

Click here to download a BlueJ project for Drag10ShirtsNicer.

Drag10ShirtsNicer Source Code

The Java source code for Drag10ShirtsNicer is below. Click on a file name to download it.

Drag10ShirtsNicer.java

import objectdraw.*;
import java.awt.*;

/*
 * Example Drag10ShirtsNicer
 
 * Drag one of 10 shirts around window, now with fixed colors and 
 * a 2D layout.
 *
 * Jim Teresco, Siena College, CSIS 120, Spring 2011
 *
 * $Id: Drag10ShirtsNicer.java 1577 2011-03-28 02:10:20Z terescoj $
 */

public class Drag10ShirtsNicer extends WindowController {

    // starting location of t-shirts
    private static final int ITEM_LEFT = 30;
    private static final int ITEM_TOP = 50;
    private static final int X_OFFSET = 90;
    private static final int Y_OFFSET = 150;
    
    // how many shirts to draw
    private static final int NUM_ROWS = 2;
    private static final int NUM_COLS = 5;
    private static final int NUM_SHIRTS = NUM_ROWS * NUM_COLS;
    
    // T-shirts on the screen -- an array!
    private TShirt[] shirts;
    
    // array of colors with initializers
    private Color[] shirtColors = { Color.blue, Color.red, Color.green,
                                    Color.yellow, Color.cyan, Color.black,
                                    Color.white, Color.gray, Color.magenta,
                                    Color.orange };

    // 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() {

        // construct the array that can hold our 10 shirts
        shirts = new TShirt[NUM_SHIRTS];

        // now create the shirts, with proper number of columns
        int nextShirtY = ITEM_TOP;
        for (int rowNum = 0; rowNum<NUM_ROWS; rowNum++) {
            int nextShirtX = ITEM_LEFT;

            for (int colNum = 0; colNum<NUM_COLS; colNum++) {

                int shirtNum = rowNum*NUM_COLS + colNum;
            
                shirts[shirtNum] = new TShirt(nextShirtX, nextShirtY, canvas);
                shirts[shirtNum].setColor(shirtColors[shirtNum]);

                nextShirtX = nextShirtX + X_OFFSET;
            }
            nextShirtY = nextShirtY + Y_OFFSET;
        }

        selectedShirt = shirts[0]; // first 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;

        dragging = false;
        // test the selected shirt (which is on top) first.
        if (selectedShirt.contains(point)) {
            dragging = true;
        } else {
            for (int shirtNum = 0; shirtNum<NUM_SHIRTS; shirtNum++) {
                if (shirts[shirtNum].contains(point)) {
                    selectedShirt = shirts[shirtNum];
                    dragging = true;
                    selectedShirt.sendToFront();
                }
            }
        }
    }

    // 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) {

        for (int shirtNum = 0; shirtNum<NUM_SHIRTS; shirtNum++) {
            shirts[shirtNum].reset();
        }
        dragging = false;
    }
}