I have added a libs folder to my project root and the libs contain two jar files. When I compile the source, I get the APK created. When I unzip the APK, I cannot see the libs folder in it? Why this behavoir, as I believe libs should be bundled with APK?
When you include a jar then a relevant code from there gets transformed into bytecode the same as your own code and it all becomes a single dex file within apk.
It is native *.so libraries which you create in C/C++ with the NDK for your project they get bundled into your apk as *.so files. Because they are not in Java.
I believe all necessary classes are put in dex file(Dalvik VM executable).
Related
In our Unity project we have a lot of jar files in Assets/Plugins/Android. I understand when Unity compiles for Android, any .jar or .aar files in that directory will make it into the compiled apk.
However, our app's Unity project has many folders next to the Assets folder, and in one of those is a hand full of jar files, such as android-support-V4.jar and google-play-services.jar. These are not in Assets/Plugins/Android, but some of the .jars in that directory depend on what's in the directory outside the Assets folder.
How can I tell if these .jars outside the Assets folder are making it into the compiled apk? I know it's a broad question, and part of it is idiosyncratic to how my company's project is set up, but basically I'm wondering if there are common or known ways to get .jars outside of the Assets folder into the apk Unity makes.
You can use a tool such as Classyshark to analyze the contents of your apk. Classyshark is developed by Google for these kinds of inspections. You can see what packages and what classes are in your apk, no matter how these were packaged.
In my current gradle based project, I'm using a library which depends on already built .so libraries in the armeabi folder in libs.
How can I add those .so files to my project?
Thanks
I created a new JAR with the .so files in a lib folder in it. Simpliest way to fix that..
I've made an android library project that uses some native libraries.
I've made the jni wrapper and put the native libs (.so) in the libs// folders. The native libs are compiled using cmake, for armeabi, armeabi-v7a, x86 and mips.
I export this project to a jar and put this jar into a "normal" android project. I then export this project to an apk and can see that my libs are bundles into it.
However, when i install the apk, the libs corresponding to the device are not copied into /data/data/com.my.app/lib and obviously, running the app complains about not finding the libs (UnsatisfiedLinkError).
I've search through SO and everywhere i can but found no answer that solved my case.
i'm using Eclipse, btw
Thanks for your help
UPDATE
OK, i've read the doc in the ndk and seen the examples, and unfortunately, i can't see the solution.
The ndk build the c code into shared libs and places them into the appropriated location in the project. But it doesn't generate anything that says that the libs must be installed with the apk.
My goal is to provide an android library (so a jar), that can be included within an android application. I don't see the real difference between what i'm doing (compile the c libs using cmake and package the jni and java compiled classes into a jar) and what is done with android.mk
If you see what i'm missing, feel free to tell me (even if its obvious).
thanks
UPDATE
i've made a dirty hack: in the libs folder of my application, i've put the jar file containing my classes and my native libs and a copy of the .so files for each arch. Suprise, the libs are no installed in /data/data/com.me.myapp/lib
It seems to confirm that it's a packaging problem.
I export this project to a jar and put this jar into a "normal"
android project. I then export this project to an apk and can see that
my libs are bundles into it.
The issue is that the Android packaging system doesn't handle with binary assets in JARs. For your application project to find and include the generated .so files, you need it to reference the library project as an 'Android library project':
Did you call ndk-build command?
See description below for details.
http://developer.android.com/tools/sdk/ndk/index.html
You can build the shared libraries for the sample apps by going into /samples// then calling the ndk-build command. The generated shared libraries will be located under /samples//libs/armeabi/ for (ARMv5TE machine code) and/or /samples//libs/armeabi-v7a/ for (ARMv7 machine code).
For some reason I can't build apk by Eclipse.
If I need to add external jar file (include *.class, *.properties..), which files (Android.mk,
AndroidManifest.xml, default.properties?) do I need to modify and how should I do this?
For a standard Ant-based build, to include a third-party JAR, make a libs/ directory in your project and copy the JAR there. Everything else is handled for you by the standard Ant build script.
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)