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Problem linking .so and .lib on android studio

I'm having trouble linking some files to my project. It's an android studio project and I want to link one external file: "Emv_lib.so" (I know that are some questions on how to link .so files, but those are about internal .so files, this is an external one.)
Beside this file, I have an emv_lib.lib and emvIIapi.h (the header file that actually contains the functions that i need to call). I cannot get this to work. I tried with CMakeList, putting the emvIIapi.h file in there, but it comes with the error: "Execution failed for task ':app:configureCMakeDebug'.
C/C++"
I follow some suggestion, to create in src/main the folder jniLibs and put your .so files in there, but it didn't work.
From my undestanding, I have to compile, somehow, either the .so files or the .lib file.
I'm new to android studio, so don't go hard on me. Thank you for your time!

Android how to extract *.so file during execution

I have one android myLibrary.jar file. But myLibrary.jar file will load the native 3 different so file. I have a.so, b.so and c.so.
When i using in my own application, it just simply put the jar file to the Android Dependencies and all 3 so files put in the libs/armeabi of the main application package.
When deploy and install on the device, these so file will be in the data/data/my-appname/lib/*.so.
Now i need to provide the sdk solution. The user side doesn't want the main application. They just want the myLibrary.jar. So i am considering about packing all 3 *.so files to the jar. I searched for the how to add to the so files to myLibrary.jar. But i still don't understand.
In this following post:
[Ant]How to add .so file into a jar and use it within jar(set the java.library.path)?
It mentioned about adding the so file to the jar and extract at runtime. But i still don't understand how to achieve that.
After trying that mentioned in the following post:
Creating a product SDK: How do I add a native lib (.so) and a jar with the SDK I am creating?
After my sample application reference the the compiled jar that included the .so file. After installing to the device, the libs/armeabi/xxx is not unpacked on the install. So i would like to know how to extract them dynamically and save them to data/data/my-appname/lib/ so that i can use with System.loadlibary(.so).
Thanks a lot.

How to call a Android ndk build .so file in another Android application?

I have an requirement which i have to build .so file using NDK build in Android and I have to call some of the methods from the .so file in my other Android application.
What I have tried so far.
I have taken the .so file from the lib folder of my Android project and put in my other application libs folder where I should call that .so file. I have used the below code:
Note: I am using ECLIPSE
static {
System.loadLibrary("NativeCode");
}
and also tried with full path of library
static {
System.loadLibrary("fullpath\NativeCode");
}
both the cases its giving unsatisfiedLinkError that mean it's not getting the path of my .so file.

You need to have your libNativeCode.so in the jni folder of your root, and not in the libs or lib folder
Here is a nice tutorial : http://www3.ntu.edu.sg/home/ehchua/programming/android/android_ndk.html
Alternatively, you can use following commands:
adb shell
$echo $PATH
What it will do is display a path like this :
/sbin:/vendor/bin:/system/sbin:/system/bin:/system/xbin
You can have your .so in any of these folders like /system, /system/bin, /system/sbin. (Remember, but you would need to manually copy it, and it is not a good idea to do so for an app)
Edit :
You can not call any JNI function in your app, because the signature. You need to have a JNI wrapper (a .so JNI lib that in turn uses the .h header file to call the JNI function of the other library). This is because JNI is very sensitive to signatures. So, as I recommended earlier, follow the tutorial !

In order to get your .so library to be loaded using loadLibrary() you'll have to copy the libNativeCode.so lib into the jniLibs/architecture folder.
The folder should be located under src/main/jniLibs/armeabi-v7a of your Android Application module (assuming you're using Android Studio).
After you copy the libraries, add the following line to your build.gradle located at the app module folder:
assert file("./src/main/jniLibs/armeabi-v7a/libNativeCode.so").exists()
After you'll complete the above steps it should load the lib properly.
If the libNativeCode.so is located at the wrong path, the Gradle build will fail.
Good luck,

Ant build Android project with dependency lib

I have two Android projects, one shared library and the app. Now I want to compile the app with dependency to the library. In Eclipse, it works very well. After that, I upload it via git to my repository and trigger Jenkins to build both projects.
My problem is, that the error occurs: "sdk/android-sdk-linux/tools/ant/build.xml:440: ../shared-lib resolve to a path with no project.properties file for project". That's clear, because in Jenkins the jobs are stored different than under Eclipse.
Another problem is, that Eclipse compiled the shared to ".jar" and Ant compiled it to "classes.jar" (is named in sdk/android-sdk-linux/tools/ant/build.xml).

Ant scripts should allow you to include whatever files you need. In your case I will suggest you move the reference to the shared-lib to local.properties file (this file should also be read by the ant script generated by update-project. Keep the adequate path for jenkins in the repository and modify the file locally for the local built. In the file in the repository you will need to have something like:
android.library.reference.1=../classes.jar
EDIT By the way the suggestion of the second properties file is just because this file is really meant to store location-specific properties.

I fixed it with copy files. The first project builds my shared-lib.jar. The other projects (phone and tablet) copy this file (shared-lib.jar) to there libs-folder and build correctly. But now I have different projects.propertieson the server and my dev-client. This one is not checked in into git.

Creating a product SDK: How do I add a native lib (.so) and a jar with the SDK I am creating?

I am creating a widget that we will provide to developer end users and it consists of a .jar and a native library (.so) built using the NDK. The JAR has a JNI interface to the dynamic library.
It's very clear on how to include an external .jar in a project but not how to include a dependent dynamic library.
How do I package up and build the .jar and .so? What are the best practices here?
I can create the JAR file using the JDK's jar command. Do I need to run dx.bat on the jar to convert to Dalvik bytecode?
I need to create a sample project showing the widget in action. How do I include this .jar and .so in a sample project that demonstrates how to use the widget?

I spent some time on this, and i just can't understand why isn't this written on wikitude documentation.... anyway follow this changes!
go to windows/preferences/android/build
uncheck the first and the second option
extract files from wikitudesdk.jar with winrar as if it is an archive, search libarchitect.so and copy it in /libs/libs/armeabi/
add wikitudesdk.jar to your build path

You should use the standard build tools included with the SDK for this. If you include the .jar files you need in the /lib directory of your project, the ant build process will convert the included class files to Dalvik bytecode format and include them in your classes.dex file for the app. Add a build.properties file to your project root as well, with one line:
external.libs.dir=lib
Depending on the version of your SDK and configuration of it, you may need to place the jar in libs rather than lib.
As for the .so, I presume that it's properly compiled using the Android NDK, or using a build script that uses the proper compiler and compiler flags that are required to successfully link the shared object on Android. If this is the case, you can include the .so file in libs/armeabi and they will be added in the jar as well. Furthermore, the dynamic library loader will know to look in this location in the .jar when you actually try to load the library from Java code.

Using ADT 12, I accomplished this by doing the following:
1) Export JAR from your library with the SO file using Eclipse. Make sure you exclude AndroidManifest.xml. This will include source code and other data, so if you are distributing, you'll want to strip these unnecessary bits out using any ZIP utility.
2) Create a directory in your App's source tree (I use "lib" directory) and copy your library JAR to it.
3) Right-click project in Eclipse and select "Configure Build Path". Add JAR and point it to JAR inside your App source tree.
4) In your Eclipse preferences, select Android/Build section and uncheck "Automatically refresh Resources and Assets folder on build". You will notice an option below that says "Force error when external jars contain native libraries." There is an ADT bug, which will supposedly be fixed in R17, which uses the wrong setting. Once it is fixed, you will use the "Force error" one (make sure it unchecked).
5) Once you build your app APK, you will have a libs/armeabi/libXXXX.so file. This will not be automatically unpacked on install. You will need to write code to extract it from your APK file into your data directory, then use System.load on the .so file in your data directory.
I have bidirectional JNI calls going from the dynamically loaded file, and even use dlopen() on it to do my custom plugin registration stuff.

Add the below lines to android.mk.
include $(BUILD_PACKAGE)
LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES := alias:libs/your.jar
include $(BUILD_MULTI_PREBUILT)