Develop Reference

AOSP include Maven JAR file in android.mk

I found similar posts but often the answer are not really correct and anyways seems to be not working for me.
I have an Android application created with Android Studio which includes java-websocket library. Now, I want to build this application inside AOSP thus I created a folder for the jar library with its own Android.mk and another folder which contains the application (with Android Studio structure) which contains its own Android.mk (modified in order to find AndroidManifest, res, java, AIDL files)
At first I had some troubles due to some incorrect parameter in the Android.mk for the jar file. Now the jar file seems to be correctly recognized and the intermediates are exported to out/ folder.
The problem now is during the build of the application since the classes exposed by the jar seems to be not available ending up in:
error: cannot find symbol WebSocket
and similar errors for any reference to the jar content.
The JAR folder contains: Android.mk Java-WebSocket-1.3.0.jar
And this is the Android.mk content
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := JavaWebSocket
LOCAL_MODULE_TAGS := optional
$(warning Going to build $(LOCAL_MODULE))
LOCAL_SRC_FILES := Java-WebSocket-1.3.0.jar
LOCAL_MODULE_CLASS := JAVA_LIBRARIES
LOCAL_MODULE_SUFFIX := $(COMMON_JAVA_PACKAGE_SUFFIX)
include $(BUILD_PREBUILT)
The application folder contains: Android.mk aidl_files app gradle build.gradle ..
(basically the Android Studio project plus the Android.mk and a folder containing AIDL (which I'll move outside later)
And this is the Android.mk file content:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_PACKAGE_NAME := MyApplication
LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES := JavaWebSocket
LOCAL_PROGUARD_ENABLED := disabled
LOCAL_MODULE_TAGS := optional
LOCAL_CERTIFICATE := platform
LOCAL_SRC_FILES := $(call all-java-files-under, app/src/main/java) \
aidl_files/my_aidl_file.aidl
LOCAL_AIDL_INCLUDES := $(LOCAL_PATH)/aidl_files
LOCAL_RESOURCE_DIR += $(LOCAL_PATH)/app/src/main/res
LOCAL_MANIFEST_FILE := app/src/main/AndroidManifest.xml
LOCAL_PRIVATE_PLATFORM_APIS := true
LOCAL_STATIC_ANDROID_LIBRARIES += \
androidx.appcompat_appcompat
include $(BUILD_PACKAGE)
I tried to merge all the informations I found in StackOverflow so far without success.
Is there any other LOCAL_something that I should set?

How do I build the arcore camera_utility shared library in NDK-BUILD?

I'm trying to build the 'arcore camera utility' library in NDK_BUILD, here: https://github.com/google-ar/arcore-unity-sdk/tree/master/Assets/GoogleARCore/Examples/ComputerVision/Plugins/src
Using this guide: https://yeephycho.github.io/2016/10/20/How-to-Use-NDK-to-Build-A-Shared-Android_Native-Library/ I was at least able to get it to compile in a libarcore_camera_utility.so file. Not only that but it was actually recognized by my app on the phone and instead of getting a DLL missing error I got the error: "EntryPointNotFoundException: Unable to find an entry point named 'TextureReader_create' in 'arcore_camera_utility'." which means it at least found the file, now.
The filesize of the .so is only 6k so it seems like I'm not compiling it correctly as the already working 32bit version that comes with the package is 100k, based on this question it seems like I'm leaving something out?: Entry point not found, Android .so file
My Android.mk file is:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := arcore_camera_utility_shared
LOCAL_C_INCLUDES += \
LOCAL_SRC_FILES := camera_utility.cc gl_utility.cc texture_reader.cc
include $(BUILD_STATIC_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := arcore_camera_utility
LOCAL_WHOLE_STATIC_LIBRARIES := arcore_camera_utility_shared
include $(BUILD_SHARED_LIBRARY)
And my Application.mk file contains:
APP_ABI := arm64-v8a
APP_PLATFORM := android-24
APP_STL := c++_static
APP_BUILD_SCRIPT := ./jni/Android.mk
Am I building it in such a way as to leave the code out?

To compile arcore_camera_utility for the arm 64bit target-
1.) Create a new directory called 'arcorelibrary', then a subdirectory called 'jni'
2.) Download this zip: https://github.com/google-ar/arcore-unity-sdk/blob/master/Assets/GoogleARCore/Examples/ComputerVision/Plugins/src/arcore_camera_utility.zip
3.) get the three .cc files and the three .h files and place them in the jni directory
4.) Create a file called 'Android.mk' and place it in the jni directory, with the following contents:
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE:= arcore_camera_utility_static
LOCAL_SRC_FILES:= camera_utility.cc gl_utility.cc texture_reader.cc
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)
LOCAL_EXPORT_LDLIBS := -llog -landroid -lEGL -lGLESv2 -lGLESv3
include $(BUILD_STATIC_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := arcore_camera_utility
LOCAL_WHOLE_STATIC_LIBRARIES := arcore_camera_utility_static
include $(BUILD_SHARED_LIBRARY)
5.) Create a file called 'Application.mk' and place it in the jni directory, with the following contents:
APP_ABI := arm64-v8a
APP_PLATFORM := android-24
APP_STL := c++_static
APP_BUILD_SCRIPT := ./jni/Android.mk
6.) Download Android NDK and unzip somewhere (The version you need depends on which Unity version you're using) https://developer.android.com/ndk/downloads/older_releases.html
7.) Open a terminal or powershell, go to the root directory (arcorelibrary) of your project
8.) Create a path to where ever you unzipped Android NDK (Powershell example):
$env:Path += ";C:\[where-ever-you-unzipped]\android-ndk-r13b-windows-x86_64\android-ndk-r13b"
9.) Run:
ndk-build.cmd

How to generate a shared library temporary and pack it into a APK package

I have a android app called "ABC" which needs to pack a jni shared library called "libxxx-jni.so". So the source tree is likes as below:
ABC
+- Android.mk
+- java
+- res
+- jni
+- Android.mk
+- xxx.cpp
The Android.mk of ABC app is:
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE_TAGS := optional
LOCAL_PACKAGE_NAME := ABC
LOCAL_SRC_FILES := $(call all-java-files-under, java)
LOCAL_RESOURCE_DIR += \
$(LOCAL_PATH)/res
LOCAL_JNI_SHARED_LIBRARIES := libxxx-jni
include $(BUILD_PACKAGE)
# Also build sub-targets under this one: the shared library.
include $(call all-makefiles-under, $(LOCAL_PATH))
And the Android.mk of jni library xxx is:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := libxxx-jni
LOCAL_SRC_FILES := xxx.cpp
LOCAL_SHARED_LIBRARIES := \
libutils \
libcutils
LOCAL_LDLIBS += -llog
LOCAL_C_INCLUDES += \
$(JNI_H_INCLUDE)
include $(BUILD_SHARED_LIBRARY)
I put these source code in android aosp source tree, and use android build environment to build whole system.
My problem is I need to pack the libxxx-jni.so into my Settings apk. Currently, after build completed, I see the libxxx-jni.so is located at /system/lib. In APK's lib sub-folder, I only see a link to the /system/lib/libxxx-jni.c.
That's not my expectation. I want to pack the so in my APK's lib sub-folder, not just a link. And I don't want to the libxxx-jni.so is appeared in /system/lib.
I didn't use IDE (eclipse or android studio), and I only use Android.mk in aosp source tree.
How should I modify these Android.mk to meet my expectation? Thanks.

Add this to Android.mk:
LOCAL_MODULE_TAGS := samples

There's several ways to achieve bundling of JNI .so's in the apk when using AOSP, basically all listed in the build system:
a) make TARGET_BUILD_APPS become true: one way to do this is by building your app via tapas instead of lunch: . build/envsetup.sh; lunch <yourlunchtarget>; m <yourapp> becomes . build/envsetup.sh; tapas <yourapp> [arm|x86|arm64|x86_64] [eng|userdebug|user]; make.
b) set LOCAL_COMPRESSED_MODULE to true.
c) set LOCAL_MODULE_TAGS to samples or tests as noted by huisinro. Not sure about the side effects and if your app is not a sample or a test this feels semantically wrong.

Build Android from Source - Add Prebuilt App with Shared Library

i've build my own androidrom from source and modified a few things.
But now i wan't to add an prebuilt .apk to the project,
read that i should make an folder in /packages/apps/
and add the .apk and an Android.mk to it with following code
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := <folder name>
LOCAL_SRC_FILES := $(LOCAL_MODULE).apk
LOCAL_MODULE_CLASS := APPS
LOCAL_MODULE_SUFFIX := $(COMMON_ANDROID_PACKAGE_SUFFIX)
LOCAL_CERTIFICATE := PRESIGNED
include $(BUILD_PREBUILT)
and the added the module to the in my case /device/sony/honami/full_honami.mk
when i now run brunch i get the error after some time that no rule for target *
so i tried some changes but nothing works for me and i can't find something where there write something other than this ...
so i added the .apk to the /vendor/cm/prebuilts folder and in the *.mk where i found the other .apks where copyed to the device i added my app and run brunch without an error.
But when i now start the app, which is on the device, it crash.
Via Logcat i found out that this apk have some .so files in it and that it can't find them.
This is because i only copied the app not the .so files in the lib directory. But i can't find some solution for my problem.
Should i now extract the .so file and copy it like the .apk to the path the app looks? or is there a better solution for doing this?
Cheers
Moritz

AOSP build system handles the shared libraries differently from Eclipse-ADT.
You will need to extract that .so from your apk and create an Android.mk to it.
To extract the .so, just unzip the apk and get it from libs folder.
Here is an example for the Android.mk to libfoo.so shared library:
LOCAL_PATH:= $(call my-dir)
# prebuilt shared library
include $(CLEAR_VARS)
LOCAL_MODULE := libfoo
LOCAL_SRC_FILES := libfoo.so
LOCAL_MODULE_SUFFIX := .so
LOCAL_MODULE_CLASS := SHARED_LIBRARIES
LOCAL_MODULE_PATH := $(TARGET_OUT)/lib
LOCAL_MODULE_TAGS := optional
include $(BUILD_PREBUILT)

How to link a prebuilt shared Library to an Android NDK project?

Here I used this Android.mk file in jni/ folder.
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
# Here we give our module name and source file(s)
LOCAL_MODULE := offlineDownload
LOCAL_SRC_FILES := offline_download.c
LOCAL_SHARED_LIBRARIES :=../lib/libpackext.so.1.0
LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
include $(BUILD_SHARED_LIBRARY)
And make one lib folder in project directory and put my prebuilt .so library and make one Android.mk file which contains following
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := packext
LOCAL_SRC_FILES := libpackext.so.1.0
LOCAL_C_INCLUDES := $(LOCAL_PATH)/../include
include $(PREBUILT_SHARED_LIBRARY)
And when i use ndk-build -B command than i got undefined reference to packageExtraction. Here I use my prebuilt library functions means I can't link my prebuilt shared library to my offlinedownload library.
So any body please help me to solved out this issue.

Here is a complete Android.mk file for using a 3rd party shared library.
The library (libffmpeg.so) is placed in the jni folder.
Its "LOCAL_EXPORT_C_INCLUDES" specifies where the header files are kept for the library.
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := ffmpeg
LOCAL_SRC_FILES := libffmpeg.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../ffmpeg/libs/arm-linux-androideabi4.7_1/include
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := ffmpegandroid
LOCAL_SRC_FILES := ffmpegandroid.c
LOCAL_SHARED_LIBRARIES := ffmpeg
include $(BUILD_SHARED_LIBRARY)
If you wanted to support multiple architectures then you could specify:
APP_ABI := armeabi armeabi-v7a x86 mips
in your jni/Application.mk and change the LOCAL_SRC_FILES to something like:
LOCAL_SRC_FILES := $(TARGET_ARCH_ABI)/libffmpeg.so
and place a libffmpeg.so at jni/armeabi/libffmpeg.so, jni/armeabi-v7a/libffmpeg.so etc ..

Android NDK official hello-libs CMake example
https://github.com/googlesamples/android-ndk/tree/840858984e1bb8a7fab37c1b7c571efbe7d6eb75/hello-libs
Just worked for me on Ubuntu 17.10 host, Android Studio 3, Android SDK 26, NDK 15.2. so I strongly recommend that you base your project on it.
The shared library is called libgperf, the key code parts are:
hello-libs/app/src/main/cpp/CMakeLists.txt:
// -L
add_library(lib_gperf SHARED IMPORTED)
set_target_properties(lib_gperf PROPERTIES IMPORTED_LOCATION
${distribution_DIR}/gperf/lib/${ANDROID_ABI}/libgperf.so)
// -I
target_include_directories(hello-libs PRIVATE
${distribution_DIR}/gperf/include)
// -lgperf
target_link_libraries(hello-libs
lib_gperf)
on C++ code, use: #include <gperf.h>
header location: hello-libs/distribution/gperf/include/gperf.h
lib location: distribution/gperf/lib/arm64-v8a/libgperf.so
app/build.gradle:
android {
sourceSets {
main {
// let gradle pack the shared library into apk
jniLibs.srcDirs = ['../distribution/gperf/lib']
Then, if you look under /data/app on the device, libgperf.so will be there as well.
If you only support some architectures, see: Gradle Build NDK target only ARM
The example git tracks the prebuilt shared libraries, but it also contains the build system to actually build them as well: https://github.com/googlesamples/android-ndk/tree/840858984e1bb8a7fab37c1b7c571efbe7d6eb75/hello-libs/gen-libs

You have to do either one of the following:
Cut and paste everything except LOCAL_PATH := $(call my-dir) from your second Android.mk into your first.
Put the following in the end of your first Android.mk:
$(call import-module,packext)
Also make sure that you set your NDK_MODULE_PATH environment variable to a path where the Android.mk-file defining the module packext can be found.
You also have to change the LOCAL_SHARED_LIBRARIES in the same way mgiza said in the first answer. I suppose the packageExtraction that you got undefined reference to is in your prebuilt library so unless you have other linking problems this should solve the issue.

Have a look at the ndk documentation for prebuilts:
android-ndk/docs/PREBUILTS.html
You have to change
LOCAL_SHARED_LIBRARIES :=../lib/libpackext.so.1.0
to
LOCAL_SHARED_LIBRARIES := packext
Be sure that your folder containing the Android.mk for the packext module is named packext and can be found in in your NDK_MODULE_PATH.