Purple Robot is an Android application for creating automated experiences on the Android platform with sensing and inference capabilities. The app was created by the Center for Behavioral Intervention Technologies at Northwestern University as an infrastructural component for a variety of behavioral and medical intervention applications.

Purple Robot is a large application that includes a variety of service integration libraries as well as full language runtimes for both the JavaScript and Scheme programming languages. Consequently, it cannot be built by traditional Android IDEs given its reliance on ProGuard to shrink installation below the 65k methods limitation imposed by Android. The instructions below describe how to create an APK Android package for your own testing and development.

Purple Robot depends upon the following packages for compilation and installation:

• Git: This may already be installed on your system.
• Android SDK: An SDK installation is included with Android Studio.
• Gradle: Install version 2.2.1.
• Java: This may already be installed.

After installing these prerequisites, open the Android SDK Manager and verify that the following packages are installed:

• Android 5.1.1 (API 22) SDK Platform
• Android SDK Build-tools 21.1.2
• Android Support Repository
• Google Repository
• Google USB Driver (or suitable ADB driver for your device)

Once the prerequisites are installed, clone the Purple Robot Git repository at

https://github.com/cbitstech/Purple-Robot.git

This will check out the Purple Robot app as well as some supporting technologies. Once the repository has been fetched, initialize and update the submodules from within the Purple-Robot folder:

git submodule init
git submodule update

These commands will retrieve the Anthracite logging and XSI-Android service integration dependencies.

Next, go to the Purple Robot folder and rename the following files:

• gradle.properties.template to gradle.properties (You may also use the existing gradle.properties to sign with the testing key already contained within the repository and skip this step.)
• local.properties.template to local.properties
• res/values/keys.xml.template to res/values/keys.xml

In local.properties, set the location of your Android SDK. In gradle.properties, set the values for your Android signing keystore and key. Refer to Google's signing documentation for more details to set up your own key.

In keys.xml, please obtain your own Google Places API key from the Google API Console to enable integration with Google Play location services. (You may also leave the key empty if you're not using those features.)

To test your installation, within the Purple Robot folder, run

 gradle clean

If that command completes successfully, you can build and install Purple Robot onto an attached Android phone by running

 gradle installRelease

If you receive an error about the Java heap size, you may need to set an environmental variable instructing Gradle to use more memory:

export GRADLE_OPTS=-Xmx2048m

On non-Unix platforms, you may also need to set your JAVA_HOME environment variable to point to you local copy of the Java Development Kit.

Once Purple Robot can be built from the command line, you can import the project into Android Studio and use that IDE as your primary Purple Robot development environment.

Once Android Studio is installed, select "Import Non-Android Studio Project" and browse to the Purple Robot directory in downloaded repository.

If prompted to use a different SDK, select Android Studio's default SDK. This will update the local.properties file.

When prompted whether to use the Gradle wrapper, select Cancel and select the location of your Gradle 2.2.1 installation. Android Studio will sync the Purple Robot build files.

Once Android Studio has successfully synced with the project, you should switch the build type to release, build the app's APK, and install it on your device.

If you have any questions or comments, please send an e-mail to Chris Karr and I'll get back to you as soon as I can.