CPSC 110-08: Computing with Mobile Phones

Reading 1: App Inventor, Create Your Own Apps, Chapter 1
Due: Friday 9/9 (before class)

CS Principles

This activity addresses the idea that computing is a creative activity and focuses on the following learning objectives:

Textbook

You can purchase a copy of the text book Wolber, Abelson, Spertus, and Looney, App Inventor: Create Your Own Android Apps. It costs around $25. We will be having reading assignments from this text throughout the semester.

There is a pre-publication version of this book available for free download. However, it is not as complete as the published version.

Reading Assignment

Read Chapter 1 of App Inventor, Getting Started with Hello Purr (16 pages). This chapter describes the basics of the App Inventor environment and walks you through the creation of the "Hello Purr" app. You can read it quickly. The material covered here is also covered in a step-by-step fashion in the next two parts of this homework.

    Reading Questions. Keep these questions in mind as you read the assigned chapter. For each question, write a short answer. Don't worry if you think you don't know the right answer. Just give it your best shot. Bring your written answers to class. We'll discuss these in class and then you can revise them. On subsequent assignments your answers will be posted to your portfolio.

  1. Think about the difference between Hello Purr's data and its behavior, or what it does with its data. How does App Inventor's Component Designer and Blocks Editor fit into this difference?

  2. Writing an app is a little like baking a cake. In what ways does the Hello Purr app resemble a recipe?

  3. An event handler is a block that handles a certain type of event. It's a piece of software. It's not the same as the event itself, which is an actual physical occurrence that happens on the phone. Give an example of an event and an event handler from the Hello Purr app and explain the relationship between them.

  4. The Sound.Vibrate block contains a slot labeled millisecs that lets you plug in a number that determines how long the phone will vibrate. This slot is known as an argument. Give an example of something akin to an argument from a recipe. Do you see how such 'arguments' make the recipe more general? Explain.

In Class on Friday

Bring your answers to the reading questions to class on Friday. In class we will get the Hello Purr app running on the lab machines.