Example

examples/libfplutil_example is a sample application which prints "Hello World" to the Android log. It's as possible to compile the application for other platforms and see "Hello World" printed to the standard output stream.

The following sections will describe:

• Setting up the build environment.
• Building the sample.
• Installing the sample.
• Running the sample.

Before Getting Started

• Install the Android SDK.
• Install the Android NDK.
• Install Python (optionally required to build with fplutil's build tools).

Build, Install and Run with fplutil

Building, installing and running the application using fplutil's build tool consists of the following steps:

• Open a command line.
• Change into the example directory.
• Run fplutil's build_all_android

For example, the following will build the application APK in debug, install the APK on an attached Android device and execute the application:

cd examples/libfplutil_example
../../bin/build_all_android -T debug -i -r

Which should display:

--------- beginning of /dev/log/main
--------- beginning of /dev/log/system
I/main    (  550): Hello, World!

Building manually with ndk-build

The following steps only need to be performed if build_all_android isn't sufficient for your build environment.

To build the shared library that constitutes the native component of the application:

• Open a terminal.
• Change into the example directory.
• Run ndk-build.

For example:

cd examples/libfplutil_example
ndk-build

Packaging the Application

This will create a shared library in the libfplutil_example/libs directory which needs to be packaged into an APK before it can be deployed to a device. To do this you need to:

• Create an Android Ant project.
• Build a debug APK to avoid the APK Signing step.

For example, the following generates a project to build against Android API Level 18 and builds an APK:

android update project --path . --target android-18 --name libfplutil_example
ant debug

This results in the application's APK in bin/libfplutil_example-debug.apk.

Deploying the Application

To run this application:

• Deploy the APK to an Android device.
• Run the application on the Android device.

For example:

adb install bin/libfplutil_example-debug.apk
adb shell am start -S -n com.google.fpl.libfplutil.example/android.app.NativeActivity

Running the Application

Finally, it's possible to view the application's output using adb logcat:

adb logcat -s main

Which should display:

--------- beginning of /dev/log/main
--------- beginning of /dev/log/system
I/main    (  550): Hello, World!