Book Image

Google App Inventor

By : Ralph Roberts
Book Image

Google App Inventor

By: Ralph Roberts

Overview of this book

<center><iframe src="http://www.youtube.com/embed/UgRhYG_bvW8" width="500" height="315" frameborder="0"></iframe></center> <p>The number of mobile apps has grown exponentially in the last two years. If you want to join the crowd, Google’s App Inventor is the easiest and best tool for you to get started with. It is a tool to create Android phone apps and uses a graphical user interface, and drag and drop methods to create apps. It’s so simple that anyone can build an app.<br /><br />Learn how Google App Inventor eliminates the mystery around programming. It is a visual language, where we simply drag and drop blocks (graphic elements representing blocks of code) in various combinations to give us applications that run on our phones or other Android-based devices. No programming background is required. Playing with blocks has never been more fun!<br /><br />The emphasis is on creating apps that work and that you understand fully. The first part of the book gives you a sound foundation in the basics, and lots of tips on how to use App Inventor. The second part is all about creating complete apps ready for real world use. The book includes apps that communicate, use databases to remember, surf the Web and other networks, use GPS and various sensors on your phone, and let you write or play games.</p>
Table of Contents (19 chapters)
Google App Inventor
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

Time for action getting the current address, longitude, and latitude


To get the current location continuously, we choose the LocationSensor1.LocationChanged frame from the My Blocks/LocationSensor1 drawer. This frame automatically generates name (local) variables for latitude, longitude, and altitude in the My Blocks/My Definitions drawer. However, we will not use the name variables—we just want this frame because it fires off every time our location changes. This constant updating is quite nice.

As we see below, we use the address_current.Text block to build and display our current location in the—wait for it, eh?—Current Location window on the phone's screen.

We start with a line return just for formatting and add the blocks (also from the My Blocks/LocationSensor1 drawer) containing the data we want. That being what the GPS system thinks is our current street address. It is a lot less accurate in guessing the address than it is with the latitude and longitude.

GPS, when you're getting...