Android-Manual-Build-Command-Line

Sample Code on the creation of Android APKs using command line & makefile only.

This is a sample/example code on how to create an android project with the command line only.

• No use of gradle, ant, maven, android.mk and all that other stuff.

Description

I prepared 2 samples:

• hello-jni: This is the same demo as the one you find in the android-ndk official sample repository. However, with the difference that I do not use gradle.

• native-activity: This should be the more interesting sample because I completely bypass having Java code - no Java UI. That means c++ wrappers are not needed nor System.loadLibrary("hellojni"); calls from Java. The entry point (main) for the program is in the .cpp file like a regular c++ software. It is a little bit difficult to understand what is going on because you have to take care of the main loop, the rendering and querying inputs yourself. It is more low-level but I think you want that kind of control. Again, no gradle involved.

Why

• Your want full flexibility and know what you do.
• You not need most of gradles services
• You do not want bloat your project.
• 15+ seconds build time via gradle is unacceptable.

Dependencies (aka what I was using)

• android built-tools 25.0.3
• andrioid ndk r14b
• Java JDK 1.8.0_131 (dex has issues with Java 1.8 for the moment, but we can compile Java 1.7 compatible code.)

How-To Build & Run

Note that in the CMakeLists.txt file you have to update the paths with your individual paths. That means, you have to download a bunch of software, place them in a folder and set up the native standalone toolchain from the android ndk.

The command to create the standalone-toolchain is

$NDK/build/tools/make_standalone_toolchain.py --arch arm64 --api 24 --install-dir some_folder

Note that api 25 is not available with ndk-r14b because there are no new features since version 24 (android-ndk guys told me).

To build & run in terminal:

cd {hello-jni, native-activity}
mkdir ./build 
cd ./build
cmake ../
make build
make deploy (phone needs to be connected to computer)

If everything goes right, your build will look like this:

To-Do

• have CMake as build-system
• remove Android.mk makefiles. Instead, compile everything by hand. This will give so much more control (no more hidden compilation flags, etc.)

Contact

Feel free to contact me if you have questions or just want to chat about it.