App Inventor for Android: Build Your Own Apps — No Experience Required!

Chapter 4: OrderDroid: A Maintainable Mobile Commerce App

In This Chapter

• Creating an application with multiple screens

• Getting data out of your App Inventor application with e-mail

• Using ActivityStarter to start other Android applications

One of the questions App Inventors ask most often is, “How do I get data out of my application?” in this chapter, you build an application that takes user data and e-mails it to a given address. This is a good method for gathering field data and storing it elsewhere. In a later project, you see how to use the TinyWebDB component to get data in and out of your applications. The e-mail method you learn in this project could be used to send data to an e-mail scraping application or be archived in a document management system such as Microsoft’s SharePoint.

The other major limitation of the current App Inventor version is that it has only one Screen1 component and no easy way to create more. In this project, you learn how to create multiple screens for your App Inventor applications. This enables you to have settings screens, multiple output screens, and so on. For the purposes of this book, I call these “imitation” screens VirtualScreens. You can use VirtualScreens whenever you want to create more than one user interface view for your applications.

The method you use to send e-mails in this project uses the ActivityStarter to call the built-in default e-mail handler. The ActivityStarter can be used to call other applications on the Android ...