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App Inventor 2, 2nd Edition
book

App Inventor 2, 2nd Edition

by David Wolber, Hal Abelson, Ellen Spertus, Liz Looney
October 2014
Beginner to intermediate
360 pages
9h 3m
English
O'Reilly Media, Inc.
Content preview from App Inventor 2, 2nd Edition

Chapter 11. Broadcast Hub

Figure 11-0.
Broadcast Hub

FrontlineSMS is a software tool used in developing countries to monitor elections, broadcast weather changes, and connect people who don’t have access to the Web but do have phones and mobile connectivity. It is the brainchild of Ken Banks, a pioneer in using mobile technology to help people in need.

The software serves as a hub for SMS text communication within a group. People send in a special code to join the group, after which they receive broadcast messages from the hub. For places with no Internet access, the broadcast hub can serve as a vital connection to the outside world.

In this chapter, you’ll create a broadcast hub app that works similarly to FrontlineSMS but runs on an Android phone. Having the hub itself on a mobile device means that the administrator can be on the move, something that is especially important in controversial situations, such as election monitoring and healthcare negotiations.

In this chapter, you’ll build a broadcast hub app for the fictitious FlashMob Dance Team (FMDT), a group that uses the hub to organize flash mob dances anywhere, anytime. People will register with the group by texting “joinFMDT” to the hub, and anyone who is registered can broadcast messages to everyone else in the group.

Your app will process received text messages in the following manner:

  1. If the text message is sent from someone not ...
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Publisher Resources

ISBN: 9781491907214Errata Page