Announcing App Inventor 2 Graphics, Animation and Charts book

Volume 4 of my App Inventor guide books series is now available in e-book and print format. The book also includes video-based tutorials to supplement the text. Back Cover Description MIT App Inventor is the fast and simple way to develop Android apps. Using a programming system that runs in your Internet browser, just drag … Continue reading Announcing App Inventor 2 Graphics, Animation and Charts book

Can you “gray out” a button until data entry is complete?

A reader asked  if it might be possible to “gray out” a button so that pressing it has no action, until appropriate data has been entered? The answer is “Yes, we can do this.” After some thought, I came up with the following simple solution. Update 1: Check the comments to this post for a … Continue reading Can you “gray out” a button until data entry is complete?

Scanning bar codes and QR Codes with App Inventor Apps

Overview App Inventor supports scanning of product identification “bar codes” and QR codes. Bar codes are typically found on consumer product packaging. QR codes are used for web addresses (so you can scan the QR code and go directly to the web address), part and product inventory tracking, and to deliver short messages. In this … Continue reading Scanning bar codes and QR Codes with App Inventor Apps

Free-Download App Inventor Text Files Cheat Sheet

Download here: App Inventor Basic Text Files Cheat Sheet (PDF) High res, suitable for printing. Feel free to share with others. App Inventor sample source code: TextFile.aia Be sure to follow the links for more information about text files and where they are stored on your device and how to transfer files to your computer. Here is … Continue reading Free-Download App Inventor Text Files Cheat Sheet

Free-Download App Inventor Location Sensor Cheat Sheet

Download here: App Inventor Location Sensor Cheat Sheet (PDF) High res, suitable for printing. Feel free to share with others. App Inventor sample source code: Location_WhereAmI.aia Here is a GIF image but use the PDF for printing – also, where it says “enter a mailing address”, that should probably be “enter a street address”! Post comments … Continue reading Free-Download App Inventor Location Sensor Cheat Sheet

Free-Download App Inventor Bluetooth Communications Cheat Sheet

Download here: App Inventor Bluetooth Cheat Sheet (PDF) Covers basic Bluetooth text communications with links to tutorials on sending numeric and binary data, and connecting to Arduino over App Inventor Bluetooth. App Inventor sample source code available here. High res, suitable for printing. Feel free to share with others. Here is a GIF image of the … Continue reading Free-Download App Inventor Bluetooth Communications Cheat Sheet

Free-Download App Inventor OrientationSensor “Cheat Sheet”!

Download here: App Inventor Orientation Sensor Cheat Sheet (PDF) High res, suitable for printing. Feel free to share with others. Here is a GIF of the cheat sheet but use the PDF for printing (higher resolution): Post comments here or on our Facebook group page. Thank you! E-Books and Printed Books If you find these tutorials … Continue reading Free-Download App Inventor OrientationSensor “Cheat Sheet”!