CoSc Lab # 6 (The Model) Due Date: Part I, Experiment classtime, Tuesday, Nov 6 th, 2018.

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1 CoSc Lab # 6 (The Model) Due Date: Part I, Experiment classtime, Tuesday, Nov 6 th, Part II, Program - by midnight, Tuesday, Nov 6 th, Again you will be required to "zip" together the three.java files (Lab3.java, Lab6.java, Lab6Model.java) into one archive file (Lab6.zip) and submit only the resulting Lab6.zip file. Submit the Lab6.zip file for grading using D2L. This procedure is the same as was required for your Lab5. Of course, you should also ALWAYS verify that your lab can be executed correctly. Submit Lab6 as done for previous labs. Again, Part I is the Experiment component and will not be accepted late. At class time on the due date, you will be required to turn in a copy of the typed experiment questions and your typed answers. Part I. Experiment. (20%) You should be aware that there is a Java reference readily available on the web; as you know that can be used to find information on all Java packages, classes, methods, etc. Some questions in Part I are designed to help familiarize you with this web site. The purpose of this lab is to familiarize you with the complete MVC model, take a look at the following diagram to see how you can set up three files you will need ( Lab6ExpView.java, Lab6ExpControl.java and Lab6ExpModel.java, we will discuss in the classroom the architecture of the MVC model). Beware, that this an initial approach to this design concept, there are many ways to implement it.

2 Part I. Experiment. (30%). Create a Lab6Experiment project using the Lab6ExpView.java, Lab6ExpControl.java, and Lab6ExpModel.java files provided along with the sounds folder. Run the Lab6ExpControl.java and play with it. Observe its operation and note that the Lab6ExpControl actually extends the Lab6ExpView not the JFrame and so it must be present in the same folder; also note that the Lab6ExpControl creates a new class m from the Lab6ExpModel.java class also present in this same folder. To do this it constructs the class by the statement: public Lab6ExpModel m = new Lab6ExpModel(this); Beware, that this an initial approach to this design concept, there are many ways to implement it. Also note that it is in the model class, that all the required methods to perform the activities of the experiment are available. Once you have been familiarized with the workings of these three classes we want you to try to make typing errors and then catch them using the try/catch statements in java. After you have a good understanding of it answer the following questions: 1. Modify Lab6ExpView.java by changing the line public JButton bcompute = new JButton("SQRT"); to private JButton bcompute = new JButton("SQRT");

3 now check the code of Lab6ExpControl.java. What do you get from eclipse? Why? 2. Make the JButton public again and now modify in Lab6ExpControl.java the line else if (e.getsource() == bstop) m.pstop(); to else if (e.getsource() == bstop) pstop(); now check the code. What do you get from eclipse? Why? 3. Restore the code to its initial state. What is the purpose of the line public Lab6ExpModel m = new Lab6ExpModel(this);? 4. Look at Lab6ExpModel.java and explain the purpose of the instruction in the constructor: c = fromc;? 5. In the Model file look at the method pcompute. What is the class type of its input parameter? What is the class type of its return value? 6. When Lab6ExpControl calls the pcompute method. Where is the result stored and What is the purpose of using the decimal.format() method? 7. Back in the Lab6ExpModel.java what does the method c.sn.loop() do? And where is the sound object located in the model or in the control? What does the notation c.sn tell you? 8. In the Lab6ExpModel.java file what is the purpose of the try/catch statements? 9. How does the Lab6ExpControl.java file report an error to the user? Part II. Programming. (70%) In this next assignment you will implement full event handling for the Schenllwich JFrame. For this you will extend the View developed for Lab3 and provide both the Controller (Lab6.java) and the Model (Lab6Model.java) in this assignment. Lab6 will extend Lab3 so you need only to copy Lab3 into your Lab6Project (as you did on Lab5) and write the new code for Lab6. Your new Lab6 will employ new event handlers: ItemListener & ListListener Its header will read: public class Lab6 extends Lab3 implements ActionListener, ItemListener, ListSelectionListener Your Lab6 will use three Listeners. Note: Recall that an ActionListener (when triggered) causes the ActionPerformed() method to run. ItemListeners execute an ItemStateChanged() method and a ListSelectionListener executes a valuechanged() method. Note. Using the MVC approach for this assignment, your project will include three classes: a view, a controller and a model. Specifically, you will use Lab3 (unchanged from its earlier state) as your view. You will use a part of your Lab5 code (but with modifications) to become your Lab6 controller.

4 You will have to add new listeners to your Lab5; therefore you will have to write a Lab6.java that will use three different types of listeners: ListSelectionListener when selecting an item from one of the JLists, an ItemListener when making a selection from the JComboBox or from one of the three JCheckBoxes. The important part here is that your Lab6 (the controller) will extend the Lab3 (the view). Again note that the Lab6 constructor method in Lab6 invokes the method constructor() of Lab3 to ensure that the initial view is displayed. Also in Lab6 you will have to create a new object as an instance of the class Lab6Model (the model) that will perform the various actions required in Lab6. Observe that there is a new JLabel needed for your Lab6 implementation, this to state the "Amount to Pay " when the order has been properly made. The desired functionality of your new version of the lab is described below. 1) Making a selection from one of the JLists causes an appropriate image to be displayed on your order JFrame. The image is a static (non-animated) image unless the "Animated" JCheckBox is selected. The animation JCheckBox is used to display an animated gif image rather than a simple jpg image. 2) The sounds JCheckBox is used to generate a sound when interacting with the widgets of the JFrame. 3) The user chooses a sandwich, drink, and side from the JLists and selects an order size (Small, Medium, Large, or XLarge) from the JComboBox. 4) When the "Place Order" JButton is pressed, the JFrame should determine the cost(show the price to pay in the JTextField) and display the JFrame with the details of the order (already done for Lab5). It also should display a plated sandwich image. 5) The "Cancel" JButton restores the JFrame to the "startup" state. For the system to work properly Lab6.class (the controller) must be invoked by the static main method; the other two classes (Lab3.class and Lab6Model.class) as well as the images and sounds folders must be located in the project folder. When you create the Lab6Model.java file you will need to include a constructor method with the same name and having as parameter a link to the controller class, i.e. Lab6 just as it is demonstrated in the Lab6Experiment code required for this assignment. Your Lab3 (and Lab6) should already provide a GUI that looks very similar to the implementation shown earlier. Provided below is our implementation demo so you can observe the look and feel that we expect from your own Lab6 implementation. PLEASE NOTE D2L will require that you submit a zip file containing the (View) Lab3.java, (Control) Lab6.java, and the (Model) Lab6Model.java files. This time submit ONLY these three.java files as a as a zip file code using D2L.

5 Images Folder Order without animation Order with animation Order completed Incomplete order Note it is very important to realize that the images folder in this case has many subfolders, this because there are many images and they are properly organized, do keep this organization when you read your images!

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