9.13. Multiple Choice Quiz App: List of Lists (Optional)

Time Estimate: 45 minutes

9.13.1. Preview

(Teacher Tube version) 		This version of the Presidents Quiz app introduces a couple of new features. One is the List Picker component, which you can see at work in the preview video. It provides the user with a list of options, letting us create multiple-choice quizzes, rather than just short-answer quizzes as in the previous version of the app.

The other feature is a complex programming construct known as a list of lists -- i.e., a list that contain sublists as its elements. The list of lists abstraction is a data structure that you will find useful not only in this app but it lots of upcoming apps.

Objectives: In this lesson you will learn to :

  • use the ListPicker component to provide choices to the user;
  • define and use a new programming abstraction, a list of lists.

9.13.2. Tutorial

To get started, open App Inventor with the List of Lists template in a separate tab and follow along with the following tutorial.

1 Use a ListPicker 2 Define a list of lists for answer choices

9.13.3. Self-Check


9.13.4. Reflection: For Your Portfolio

Create a page named List of Lists under the Reflections category of your portfolio and answer the following questions.

  1. Describe how using a list of lists allowed the Presidents Quiz app to have more variety.