Category Archives: Android Development

FIRST Tech Challenge (Robotics) can now use App Inventor

Early in 2015, FIRST announced that the First Tech Challenge (FTC) robotics platform would be powered by the Qualcomm Snapdragon processor (the same processor used in most Android phones).

Starting with the Fall 2015 FTC competition, students can now control the robot using App Inventor. (Go here and page down to App Inventor Download and Resources and follow that link).

FTC uses a version of App Inventor that is installed on a local computer rather than running over the Internet, as we do with MIT App Inventor.

About FIRST

FIRST robotics is an “academic sport” for the mind as teams are faced with the challenge of conceptualizing, designing and building a complex robot to solve a challenge. The Mission of FIRST Robotics:

“Our mission is to inspire young people to be science and technology leaders, by engaging them in exciting mentor-based programs that build science, engineering and technology skills, that inspire innovation, and that foster well-rounded life capabilities including self-confidence, communication, and leadership.”

Volunteering

I am in my 8th year of volunteering as an engineering mentor to high school robotics teams. I am currently a volunteer with Glencoe High School’s Team #4488 “Shockwave” team where I am the lead mentor for Apps Software. Our team is a student-led team. The students make the design choices and implement the solutions. The mentors assist with technical and management training and specialized learning.

Our team, like many FIRST teams, is run similar to a business with separate sub-teams not only for robotics (mechanical, electrical, robot programming, CAD) but also other functions (marketing, business, strategy, web and applications software, graphic design) and even an animation team. Our applications team produces support software for the entire team by creating custom tablet apps and Windows applications software that assist in various information collection, analysis and processing functions. Last year, the team also created a robotics game that is available in the Google Play store.

There are many opportunities for volunteering – from technical engineering to business and marketing, graphic and art design, wood and metal working, CAD, and teaching. Visit usfirst.org to learn more!

How to Place Your App Inventor Apps in the Google Play Store

An all new tutorial on this subject is available here as of May 2016! There is still some great information below – read both!

Apps you create in App Inventor may be added to the Google Play Store.

The process is not difficult but there are many steps to the process and you will need to create some graphic images to illustrate and promote your app in the store.

Summary of the Steps

  • Set your app’s VersionCode and VersionName.
  • Apply for a Google Developer account (one time fee of US $25 after which you can upload an unlimited number of apps, forever).
  • Create at least two and up to 8 screenshots of your app for display in the store’s app listing.
  • Create a “feature graphic” and a high resolution icon for use in the store listing.
  • Use the App Inventor provided keystore file, or use a keystore file you have created elsewhere or previously.
  • Build and export your app as a .apk file to your computer.
  • Create a title for your app in the store
  • Write a description for your app to appear in the store
  • Decide on free versus paid (paid requires a “merchant account” to be set up).
  • Upload your apk file, keystore file, image files and title and description, and provide some additional information (such as product category, pricing, and target audience).

Continue reading How to Place Your App Inventor Apps in the Google Play Store

How to use the “2 Button” Notifier dialog box

A reader asked, “When using the 2 button Notifier dialog, how do we know which button was pressed?

The 2 button Notifier dialog alert box displays 3 buttons(!) – the first two have values you specify, such as “Ok” and “Done”, as shown here, and the third is an optional generic “Cancel” button:

Screenshot_2015-09-11-15-07-15

The Notifier component block is a procedure call that has no return value – so how can you determine which button was selected?

The answer is that the selected button is returned to a separate event handler.

Continue reading How to use the “2 Button” Notifier dialog box

How did you discover MIT App Inventor?

How did you discover MIT App Inventor?

I discovered App Inventor just as Google was handing AI classic off to MIT. At the time I was looking at different kinds of development tools for mobile devices, and App Inventor showed up in some online searches.

I took a look at it and found it  intriguing – at the time, AI classic did not seem quite capable of doing the things I was likely to need, but I intended to keep an eye on it.

A few months later, I was asked if we could quickly train some high school students to write Android apps? I have been a volunteer engineering mentor with FIRST Robotics programs for eight years. The new high school team where I was volunteering had intriguing ideas for mobile apps. When I was asked about the feasibility of quickly building some Android apps, I immediately proposed MIT App Inventor!

Our first student was so enthralled he literally stayed up half the night teaching himself App Inventor and soon was writing bundles of code for our Android tablet applications. Eventually another student joined the effort (from an iPhone background!) and rapidly came up to speed, writing a neat app in App Inventor.

Continue reading How did you discover MIT App Inventor?

New Linux OS version designed for Android & App Inventor app development

The Appril release of Quirky Linux includes the Android SDK (Software Development Kit), Android Studio, App Inventor, Oracle JDK (Java Development Kit), and LiveCode tools, as well as all of their dependencies, together with the JWM (Joe’s Window Manager) and ROX, providing one of the lightest environments for Android app developers.

“The intention is to have out-of-the-box, just-click-and-get-going Android app development, catering for total non-programmers with App Inventor, through intermediate with LiveCode, to hard-core coders with Android Studio,” says Barry Kauler, Puppy Linux creator.

Source: Puppy Linux’s Sister Quirky 7.1 Distro Arrives with Tools for Android App Developers

It actually runs the App Inventor system on the computer – does not require access to appinventor.mit.edu.

Download here (its free, of course). I have not tried this yet but would be interested to hear reports from users!

 

Off topic: My Photo Guide 2.0 app for Android is available – for free

Version 2.0 of my Photo Guide app for Android is now available – it is free, no ads either.  No special permissions are required to install. Only works on Android 5 or newer.

Works on Android 4.4 and newer.

(Update: An updated version for 4.4 will be available in the store in about 1-2 days – its been uploaded and is awaiting Google processing. In the mean time, the version in the store works on Android 5.x).

 Screen shot:xEJ7UDMI_W9zcV7U_3cY-NK-CrMkJj-E7NgL7cjFfmjp_3AArfP1Ekt6kv6kyDjsNGo=h900 Click on the icon to go direct to the Google Play store and request a download:

wj_p3SzzexZS2tvqhESceRXSrLUAkZwXOV_YC8_QbyJY4l3VPv53ier4fhWSCs3GOK4=w300Alternate link if a browser blocker interferes with that:  https://play.google.com/store/apps/details?id=com.pevest.photoguide

This app was originally written using the Eclipse software development system, and the PhoneGap and JQuery Mobile libraries. The new version was converted to use Cordova (similar to PhoneGap) and the project was transferred to the new Android Studio for compilation and testing. This app was NOT written using MIT App Inventor.

Google to end support of Eclipse for Android s/w development

I posted the following on my App Inventor Facebook page – only a fraction of readers use the FB page so I am cross posting back over this blog. Usually I post items on the blog first, and then those end up on FB.

If you would like to follow the Facebook page, click here and then click on Like and also select “Get Notifications”.


Google will end support for Android Software development using the Eclipse Integrated Development Environment as they migrate development over to Google’s own Android Studio.

See here for details: http://www.androidcentral.com/google-stop-development-and-support-android-developer-tools-eclipse

This does NOT impact MIT App Inventor coders!

Eclipse and Android Studio are used for developing Android apps written in the Java programming language, and relying on the Android Software Development Kit of libraries of code. These tools are used to develop most Android apps as they are capable of using all of the features provided by Android, while MIT App Inventor limits us to a subset.

I just spent several days getting Android Studio up and running and reconfiguring an old project so that it now builds entirely in Android Studio. That Eclipse will be going away was sort of obvious.

———-

I have completed all of the text for my next App Inventor e-book. However, once I finished, I decided to add even more! I am hard at work on one more chapter! I think a lot of people are going to love Volume 3 and I cannot wait to share it with you! However, its the middle of summer and my wife would like us to take an actual vacation so I need to work hard on my vacation skills for a few days before I can wrap up the book!

I hope to share a lot more with you in very early August.

TOO MANY TOTES! Android game written in App Inventor

It’s free – the TOO MANY TOTES! game for Android devices – download at the Google Play Store.

The app was created by student members of the Glencoe High School FIRST Robotics Team #4488 “Shockwave” and was developed using MIT App Inventor. The Android game is inspired by the 2015 FIRST Robotics Competition game called “Recycle Rush”. In the game, robots must stack a variety of container “totes” and a trash can on top and relocate the containers to a recycle zone on the playing field. Students design, build and test their robots – weighing up to about 120 pounds or 55 kilograms – these are large, complex pieces of mechanics, controlled by an advanced system controller, with control software also written by the student team. To learn more about FIRST Robotics, visit the web site at http://usfirst.org

I am one of many volunteer engineering mentors to the Shockwave Team. This year, I was mentor for the applications software team, that has developed a number of Android apps (the game is the only one publicly available), an Excel spreadsheet (written in VBA) to analyze data and develop optimal strategies, plus another app written in Python to process text comments about other robotics teams.

The team’s Android apps are written using MIT App Inventor.

 

Update: Reading and writing text files with App Inventor

I previously posted a short tutorial on writing to and reading from text files stored on an Android device, using an App Inventor app.

Unfortunately, as some comments noted, the file being created seems to disappear – the data is written and can be read back – but the file is no where to be found on the phone!

After some research, I now know where the file is – and also how to copy the file from the phone (or tablet) to your personal computer.  While the solution to finding and saving the file to your computer is ultimately easy, I need to update the tutorial and explain some things about the Android file system. You will also need to install a free app on your phone in order to copy the file to your computer.

I have posted an updated tutorial that explains the details and shows how to store your files in the right location, how to find them (they are hidden from most views), and how to copy them to your personal computer.