UNIT 1 REVIEW QUESTIONS
Richard H. Hendrix Jr.
Post University
Author Note
Programming Fundamentals CIS 200 taught by Mohamed Ben Haj Frej
Chapter 1 Review Questions
3. Describe the role of each of the five main areas of the Alice interface: the World window, the Object tree, the Details area, the Editor area, and the Events area.
 The World Window – Contains a view of the virtual Alice world. The set of blue arrows below the window controls the Alice camera, which provides you with the view in the window.
 The Object Tree – The object tree appears to the left of the World window. It shows the objects in the current Alice world organized as a tree of tiles, with a tile for each object. The plus sign next to an object shows that it has sub parts, which may be seen by clicking the plus sign.
 The Details Area – The Details area of the Alice interface is located below the Object tree. It has tabs to show properties, methods, and functions for the currently selected Alice object. Properties contain information about an object, such as its color and position in the world. Methods are programs that manipulate an object. A function is a method that returns a value, such as the distance between two objects.
 The Editor Area – The largest area of the Alice interface is the Editor area, which appears to the right of the Details area. Here, you assemble and edit methods by clicking and dragging tiles from other parts of the interface. The bottom of the Editor area has a row of logic and control tiles that can be used to put branching, looping, and other logical structures into the algorithms that will make up an object’s methods.
 The Events Area – The Events area in Alice is above the Editor area. The Events area shows existing events and is used to create new events. An event consists of a condition, called an event trigger, and a method, called an event handler. Whenever the event trigger occurs, the event handler is called into action.
Chapter 2 Review Questions
5. How does the practice of object-oriented programming encourage the development of reusable code? Reusable code makes programming easier because you need to develop the solution to a problem only once; then you can use that code whenever you need it. You can also save the modules you have developed and reuse them later in other projects, modifying them if necessary to fit new situations. Over time, you can build libraries of software modules for different tasks. All computer programs, from the lowest levels of an operation system that directly control hardware to the most complex user applications, are made up of layers of short programming modules that are constantly reused in different situations. Object-oriented programming, by its very nature, encourages the development of reusable code. Objects created for one project can be reused as needed for other projects.
8. What are the differences between primitive methods and user-defined methods in Alice? Which of these are encapsulated methods, and what does that mean? Alice objects have two kinds of methods – primitive methods and user-defined methods. Primitive methods are built-in, predefined methods that are part of each Alice object. They provide simple basic behaviors, such as move, turn, and roll. User-defined methods are written by people who use Alice. Some of the objects in the Alice object galleries already include user-defined methods in addition to the standard set of primitive methods. Primitive methods are also encapsulated methods. Encapsulation means that the details of a method are hidden from the user; the user cannot see or edit the details of the method. All primitive methods are encapsulated.

References
Herbert, C. W. (2011). An Introduction to Programming Using Alice 2.2 (2nd ed.). Boston: Course Technology.