| | | Part 1: |
Your program should begin with three washbaskets on the screen (for our purposes they can just be rectangles or squares). One is labeled "whites", one "darks", and the last "colors". An image showing the kind of display we have in mind appears below. When the simulation begins, a color swatch will appear on the screen. The user ("laundry trainee") should then click in the corresponding basket. If the user is correct, the program should randomly select a new color for the next item and display it on the screen. For this part of the assignment you may just select among the three colors Color.WHITE, Color.RED, and Color.BLACK when creating items of clothing. If the user clicks on an incorrect basket, the original item remains in position for another try.
You will need to design a new class that is an extension of the WindowController class which will display the wash baskets and the item to be sorted. You might want to try laying out where all the items go on some graph paper. The picture should look more or less like the one we provided here..
When the program begins, place all the wash baskets (with labels) on the screen. Then, add the item of clothing that is to be sorted. For simplicity you might as well always make the first item have color white. The item should actually consist of two rectangles, a FilledRect which is the appropriate color and a FramedRect which is the same size, but lays on top of the filled rectangle to form a border (otherwise it will be awfully difficult to see a white item!)
When you lay out the wash baskets and item, make up constants (private static final ...) for all the relevant information. This will make it easier to change things around and also make your program much, much easier to read (presuming you give constants good names). Constant names are by convention written with all capital letters and underscores, e.g. THIS_IS_A_CONSTANT. Your constants may be (and often should be) more complex objects like Location. You can initialize constants with the results of a constructor:
private static final Location SOME_LOCN = new Location(100,200);
Remember that you may NOT have constants whose definition uses canvas (e.g., no FramedRect constants). Other good candidates for constants are: he widths and heights of wash baskets and the item to be sorted, coordinates of the upper left corner of each of these, etc..
Once you have done the layout and figured out how to generate new items, all you have to do is to write the code for the method onMouseClick. Because you may be generating the item in one method (begin) and checking to see if the user clicked in the appropriate basket in a different method (the onMouseClick method), you will need to associate some information with an instance variable that will enable onMouseClick to determine which is the correct basket. An appropriate way to do this is to use an instance variable of type FramedRect.
When you generate a new item (in either begin or onMouseClick), you will associate this variable with the rectangle/basket in which an item of its color should be placed. That way when the user clicks on a basket, onMouseClick can simply check to see if the rectangle currently associated with the instance variable contains the point where the mouse was clicked. Then, onMouseClick will either select a new color for the item (if the user was correct) or wait until the user clicks again (if incorrect).
Think carefully about those last two paragraphs and what they're saying!
One odd feature of the simple interface that may bother you a bit is a result of the fact that the program selects laundry items randomly. Because the selection is truly random it sometimes picks the same color twice in a row. When this happens and you click on the correct basket for the first item you will get the feeling that the program ignored you. Even though it has actually displayed a new item, the new item looks just like the old one, so you may think nothing changed. Don't let this trick you into thinking that your version of the program (or ours) isn't working correctly. The more advanced interface in part 2 includes counters in the display that eliminate this problem.
We have provided a class in the objectdraw package which helps to generate random numbers. This will be used to determine the next color for the item.
Suppose you wish to generate random integers in the range from m to n (where m <= n). Let generator be an instance variable declared to be of type RandomIntGenerator. Create a new random number generator from class RandomIntGenerator, and assign it to generator:
generator = new RandomIntGenerator(m,n);
Now every time you want a new random integer in that range, simply invoke the method
which will return a randomly chosen integer between m and n (inclusive). Thus to generate integers between 1 and 3 (say, standing for white, dark, and colored), use
If n is the value of generator.nextValue(), make the color of the item be Color.WHITE if n is 1, Color.BLACK if n is 2, and Color.RED if n is 3.
| | | Part 1: |