I'm currently building an app that has to interact with a server. I have some classes that are defined in the server that I need to use in my app. I've tried the following to import my classes.
Add the server project as a library for my app project
Export my server project into a jar file and then copy it to my app project and make it its library.
Both methods allowed me to not have any compile time errors, however, when running the app, whenever the app uses one of the classes referenced from server project it will crash.
I debugged and whenever I get to the class (of the server) it would jump to Engine.class in the method onTickUpdate() and then crash.
Any ideas?
It is possible, that your server library is using some other java libraries, which you haven't exported from your android project.
At compile time, since you have those libraries in your build path, everything works fine, but the dex compiler will only export classes that you have explicitly marked for export.
You may want to check which reference is causing the app to crash, extract the class files from your apk, and see if that class is present or not.
Related
I'm trying to create bindings for the android sdk provided here https://www.nmi.com/sdks-and-apis#CDNA. The binding project builds, and I can add it into my xamarin android project but as soon as I include it I get the following error/s.
error: package com.creditcall.chipdnamobile does not exist
com.creditcall.chipdnamobile.IApplicationSelectionListener ChipDnaSample.Android
C:\Users\mikee\Documents\GitHub\ChipDna\ChipDnaSample\ChipDnaSample.Android\obj\Debug\90\android\src\mono\com\creditcall\chipdnamobile\IApplicationSelectionListenerImplementor.java 8
error: package com.creditcall.chipdnamobile does not exist private
native void n_onAvailablePinPads
(com.creditcall.chipdnamobile.Parameters
p0); ChipDnaSample.Android C:\Users\mikee\Documents\GitHub\ChipDna\ChipDnaSample\ChipDnaSample.Android\obj\Debug\90\android\src\mono\com\creditcall\chipdnamobile\IAvailablePinPadsListenerImplementor.java 33
There are 64 errors of the same nature just referencing different classes. I've put all the code on GitHub here
If I go into Obj/Release/generated/src I can find IApplicationSelectionListener so it is created some binding but it doesn't actually work. Could someone point me in the right direction about what I need to do to correct errors such as these?
Thanks
You have to change the build type of the jars. The java compile can't find it, because it's not present at compile time.
Change
InputJar to EmbeddedInputJar for ChipDnaMobile.jar
ReferenceJar to EmbeddedReferenceJar for CardEaseXMLClient.jar
For more info see: https://learn.microsoft.com/en-us/xamarin/android/platform/binding-java-library/binding-a-jar
The important sentences:
Typically, you use the EmbeddedJar build action so that the .JAR is automatically packaged into the bindings library. This is the simplest option – Java bytecode in the .JAR is converted into Dex bytecode and is embedded (along with the Managed Callable Wrappers) into your APK. If you want to keep the .JAR separate from the bindings library, you can use the InputJar option; however, you must ensure that the .JAR file is available on the device that runs your app.
I have an application that's written with Unity. It uses a custom Application and Activity class. Previously this has worked just fine but I've recently switched to using gradle to perform the build instead of Unity's deprecated internal build process. My Application and Activity classes are located in a library that's in the form of an aar file. The custom classes are referenced from a the and tags of a custom AndroidManifest.
I can see that the classes are present in the aar. I can see that the generated AndroidManifest references these class. I can see the dependency on this library in the generated build.gradle file. I can tell that the build process is actually referencing this library in some form. However, these classes are not present in the resulting APK, resulting in a crash on launch.
I do not have proguard or anything similar enabled. I can tell that this is a new problem because older versions of the APK do have those classes. What could be causing these classes to not be included in the resulting APK?
The package that contained those classes had the same name as the one generated by Unity. I changed the package name and everything seems to be working now.
I have services_intermediates.jar that contains com.android.server.devicepolicy.DevicePolicyManagerService. Using this I can compile my code (that uses DPMS) but it crashes when run on device reporting no class DevicePolicyManagerService found.
I don't want to package the whole intermediate jar with my app and so I use "provided" in gradle dependency not "compile".
On a broader perspective, how to use classes that are under /framework in AOSP but not available at runtime for use in some application package?
Hi I am working on a Android native application.
There is 'abc.so' files which depend on some 'xyz.so.1' file. All of the required files are available in the project structure before building, but the '.so.1' are not a part of the generated .apk file (I checked the apk file by unpacking).
This is causing in a "'java.lang.UnsatisfiedLinkError' Couldnt load 'abc.so.1' from loader dalvik" when trying to run the application.
I dont want to push the .so.1 file as the phone is not rooted and runs on a production build. How do I include the .so.1 files as a part of the APK?
Thank you.
I think you havent got the concept of loading native libraries to Java through JNI.
First you define the native methods in java and do the corresponding implementation in the native and compile it (you have to register the native methods by either 1) following a naming convention 2) registering the native methods in jni_onload...i think you must have done this, if not check http://www.ntu.edu.sg/home/ehchua/programming/android/android_ndk.html)
Next, you have to load the library before any call can be made to native. This has to be done once. You can do it in an activity by defining:
static{
System.loadLibrary("mylib.so");
}
Note while compiling the library you will have got the library name as libXYZ.so, but when loading the library in java the "lib" should be omitted ,just system.loadlibrary(XYZ.so)
If you are using NDK the library would have been already copied to Java project > libs > armeabi folder , if not you have to copy your lib.so there
Now if you have multiple shared libraries , you should load the least dependent lib.so first , followed by second etc i.e.
Static {
System.loadLibrary(independent_lib.so); // should depend on only android libs
System.loadLibrary(next_dependent_lib1.so); //can depend on android libs and independent_lib.so
System.loadLibrary(next_dependent_lib2.so); //can depend on android libs,independent_lib.so,next_dependent_lib1.so
.....
....
..
}
If you jumble up, the VM will not be able to link the libraries and throw a unsatisfied link error.
Lastly, all this .so s will be part of your apk and it will be pushed to the system libs only runtime. Unless its a rooted phone you cannot extract the .so. If you follow the above method you will not need to push any .so to the system. Only build on eclipse/cygwin and run
Hope this helps,
Regards,
Shrish
I have seen this question, and have some more doubts regarding creating a jar file which I can distribute and can be used in any android applications.
What my requirement is
As I said, I want to build and distribute a closed source library. I
don't want the source code to be visible.
In that library I don't want to use any assets, layouts, resources
etc. But I want to use some android specific codes, like getting
android device id.
The most popular answer in the above linked SO question tells to create a regular java project and import android.jar in it. I tried to do that, but I don't know how to add android.jar to any java project. I would like to get some clarification on that too.
Moreover I would like to know if there are any other methods using android sdk itself (without using java project) create a closed source library jar file.
I think what I want is possible, since google analytics for android native apps seems to have done it. I am sure in the .jar file they distribute they are using android specific codes, since there seems no other way for them to get the device information to display in the analytics viewer.
EDIT : CAN SOMEONE CLARIFY THIS??
I think I have made some progress. This is what I have done
Created a regular android project (not library project, the "is
Library" checkmark is unchecked)
In the project I have coded out my logic. It uses some android
specific classes like SharedPreference, UUID, PackageManager. But
nothing related with assets, layouts also no class extending
Activity. Just a java class extending java.lang.object
Exported the project using Project->rightclick->export->Java->JAR
file. In the next screen I unchecked the checkbox near
AndroidManifest.xml. Set a destination directory to export and
clicked next thrice with keeping the default settings. Then I clicked
Finish, and got a lovely libMyLibraryName.jar at my desktop.
Then I created another android project, added this libMyLibraryName.jar to new project using project->rightclick->properties->java build path -> libraries->add external jar.
And I tried to use my class in the library, in my new project
MyLibraryClass objClass = new MyLibraryClass(this);
And I was able to compile and run successfully. I even sent the library to one of my co worker who was able to use the library in his on machine (Just making sure library project in my workspace wont influence the project using it).
Now I have 2 questions.
1) My first question is , what they meant by the term "true library" in the below given documentation ? Is it any non android java project which can be exported to a JAR file?
However, a library project differs from an standard Android
application project in that you cannot compile it directly to its own
.apk and run it on an Android device. Similarly, you cannot export
the library project to a self-contained JAR file, as you would do
for a true library. Instead, you must compile the library indirectly,
by referencing the library in the dependent application and building
that application.
Well this portion is taken from documentation under title "Library Projects".
2) My second question is, anything wrong with the way I have created the JAR file? Any possible pitfalls which might bite me back later? I would like to make sure I am not doing something terribly wrong, before using it in my important projects.
I might add that I didn't try the method of creating a JAVA project and importing android.jar. I am ready to try that one, if what I have done currently is wrong.
The android.jar will be located where you installed your Android SDK. Under the platforms directory there should be a number of other directories named android-<version>. The android.jar will be there. Choose the one specific to the minimum android version you are targeting.
Once you have that, copy it into your project. If you're using eclipse I think you can just cut and paste jars straight into your project, right click and add it to build path. If you're not using eclipse or any other IDE, you just need to ensure that the android.jar is on the classpath when building your jar file.
After that your newly built android library can be dropped into any Android project.
In answer to your additional questions:
What they mean by a true library is a jar file as opposed to an Android library project.
I don't think there's anything wrong with the way you created the jar file. I would have made it using the android.jar as I mentioned above but your way should also work. To verify this I would examine the jar contents and make sure all you have in there is .class files.