Android NDK, CMake with other libraries

Question

So I am trying to build and test out a CMake with the Android NDK on Android Studio. I can get my library to compile, but it doesn\'t seem to want to pull any third-party depend

Answer 1

The process could be little long it will depend on your android skills.

An example could be similar to this process:

• Crosscompile sfml.
• Create your jni bridge
• Generate with cmake the project and compile
• Copy your files to android studio. create java loading library code.

I guess that you have crosscompiled sfml and you know how works crosscompiling process, if I am wrong check these link below:

Tutorial: https://github.com/SFML/SFML/wiki/Tutorial:-Building-SFML-for-Android

Source code: https://github.com/SFML/SFML

Toolchain: https://github.com/SFML/SFML/blob/master/cmake/toolchains/android.toolchain.cmake

Changes on your cmake: add this file

FIND_PACKAGE(SFML required)

In cmake put your SFML build directory and cmake will fills your VARIABLES automatically for instance this variables:

set(SFML_PATH ${ANDROID_NDK}/sources/sfml)
set(SFML_LIB_PATH ${SFML_PATH}/lib/${ANDROID_NDK_ABI_NAME})

set(SFML_LIB_SYSTEM ${SFML_LIB_PATH}/libsfml-system.so)
set(SFML_LIB_AUDIO ${SFML_LIB_PATH}/libsfml-audio.so)
set(SFML_LIB_GRAPHICS ${SFML_LIB_PATH}/libsfml-graphics.so)
set(SFML_LIB_NETWORK ${SFML_LIB_PATH}/libsfml-network.so)
set(SFML_LIB_WINDOW ${SFML_LIB_PATH}/libsfml-window.so)
set(SFML_LIB_ACTIVITY ${SFML_LIB_PATH}/libsfml-activity.so)
set(SFML_LIB_MAIN ${SFML_LIB_PATH}/libsfml-main.a) 

There are two ways to make android studio native apps:

Easy way: Create JNI bridge:

Crosscompile your cmake script and copy your lib to app/src/main/jniLibs

add library in execution time

code:

try
{
  Log.v(LOG_TAG, "adding your library");
  System.loadLibrary(your_library);
}
catch(UnsatisfiedLinkError e)
{
 Log.e(LOG_TAG,e.getMessage());
}

More complete way (it allows to debug library)

Create your ndk module in gradle example

android.ndk {
    moduleName = "your_library"
    cppFlags.add("-fexceptions")
    //cppFlags.add("-std=c++11")
    //cFlags.add("-fopenmp")
    cppFlags.add("-I" + file("src/main/jni").absolutePath)
    stl = "gnustl_shared" // Which STL library to use: gnustl or stlport
    ldLibs.addAll(["android", "EGL", "GLESv2", "dl", "log", "z"])
    String libsDir = curDir.absolutePath + "/src/main/jniLibs/armeabi/"
    ldLibs.add(libsDir + "your_native_lib.so")
}