I'm just getting started in Android development, and use Netbeans with NBAndroid and SDK 17.
I'd like to use the same Java source code in my Java and Android app.
http://developer.android.com/guide/developing/projects/projects-eclipse.html says how to do it in Eclipse (although it is sketchy on the .JAR connection thing), but I can't seem to make it work in NB.
Based on that link, My understanding is that the correct setup for the Android app is an Android Application project which references an Android Library project which in turn references a .JAR library produced by a Java Library project. I could then also have a Java Application project referring to the same Java Library project.
So, I've set up this project structure... I have an AndroidApp project which is a basic HelloAndroid Activity in a com.ex package. This project includes an AndroidLib library project in the Libraries folder. I also have a LibClass.java file which defines a simple LibClass class which has one function getText() that just returns a String to be displayed. The MainActivity in the AndroidApp calls this to get the String to output.
When I put LibClass.java directly into the AndroidLib project, everything is fine.
But what I want to do is to share the source code with Java.
So I want to move the LibClass.java into the JavaLib library, whose .JAR file is included in the AndroidLib project. However, when I tried that, I get an error in the MainActivity class, complaining it can't find LibClass. Looking at the Projects window, I can see LibClass.class inside the com.ex package in the JavaLib.jar in the Libraries folder of the AndroidLib project. And AndroidLib is visible in the Libraries folder of the AndroidApp project, but it doesn't show any packages or other contents there.
So I feel like I'm just one step away from making this work. Do I need to do something with one or other of the AndroidManifest files perhaps? Or do something with the build.xml files? Or am I on the wrong track altogether?
I'd be really grateful if someone could post a how-to for this.
I'm trying something similar; I've got Java EE projects, built using Eclipse, and I'm trying to utilize some of that code from my Android projects. This should give me a shared codebase rather than a bunch of confusing SVN externals which I've had to endure before.
Rather than creating JAR files I've found that working with the source and building for the platform works best (well, it has been working but I've got a problem with it at the moment). So, what I'm doing is:
c:\MySvnFolderStructure\MyJavaProjectFolder\src\ (and then all the source under that)
c:\MySvnFolderStructure\MyJavaProjectFolder\android\ (and all the Eclipse Android project gubbins)
c:\MySvnFolderStructure\MyJavaProjectFolder\jee\ (and all the Eclipse JEE project gubbins)
The Android and Java EE projects do not have their own src folders, they both link to the src folder in their parent folder. What this means is that each of the Java implementations is building its own byte code version from the source, and using its own external libraries (like the Apache HTTP ones, for example).
Naturally they can't share stuff like awt (as mentioned in another post), but there's plenty of stuff that does cross-over especially if it's core Java classes that are being used.
Also, it's proving a bit tricky writing JUnit tests as there needs to be some duplication of the test code at the moment because the Android ones need extra instrumentation, but I'm working on it.
Also, see this post about relative paths in Eclipse, which means the folders can be checked-out to different places on different machines (like we all do with our version control check-outs) and still be shared.
if I understand your situation correct, you are trying to use a custom java library for both your android and java applications.
For this scenario, you can build the java library first. Instead of adding the java library jar as android library, you can drop the jar directly inside the libs folder of android project and add it to android project's build path.
If you are using ANT scripts for building the java library jar , you can consider adding the source files also as part of jar. This will help you get code assistance when you develop the android part. But this part is purely optional.
The problem is that the Java platform in Android is different from the JDK platform.
In particular, the .JAR library CANNOT refer to anything that is not icluded in the Android platform. An example of things you can't refer to is java.awt.* (except you can have java.awt.fonts).
There is also a difference between JDK String and Android String -- Android does not implement the isEmpty() method.
Related
The question have basically two parts, because answers can "deactivate" other questions:
Can I use android application projects (written in Android Studio) in a Unity game engine project somehow? If yes, the questions below are not important, but I think the answer is no.
There are Android java developers, and there are Unity game engine c# developers in here. Some of us need to create an Android Studio application project, and they should have some kind of visual surface for that during the debugging.
After this, it would be better if they would be able to give the code to us as a library project, because a jar file should be created for the Unity, because the final surface of the app will be in Unity.
I know there are topics about "how to convert an application project into library project", and they works perfectly in a simple example project. But this can't be made easily, if the R method and R variable calls (or I don't know the name of that, R.id.something and R.something, etc.) are in a lot of java files. It's a lot of work cutting them out. I simply can't build the library app, if it has these R things in them. It was the case in a big Android application project, but I don't know if there would be a good workflow idea for a new project.
Since I'm not an android developer, I don't know how should this workflow in a new project to be made easily. Any idea?
The "R" in android development refers to the R class used to access the res folder in an android project, wich contains all other resources needed (images, layouts, strings)
Unity allows you to access native and custom plugins that you can import to your editor, I recomend giving a good read to the official documentation to Plugins for android in the unity website
https://docs.unity3d.com/Manual/PluginsForAndroid.html
The Android plugin mechanism also allows Java to be used to enable interaction with the Android OS.
There are several ways to create a Java plugin but the result in each case is that you end up with a .jar file containing the .class files for your plugin. One approach is to download the JDK, then compile your .java files from the command line with javac. This will create .class files which you can then package into a .jar with the jar command line tool.
I have a C++ codebase that is currently set up in Visual Studio (to run on Windows), with multiple Projects with inter-dependencies. I'm trying to bring it over to Android Studio, to get it running on Android.
I'm familiar with Visual Studio and C++, but quite new to Android Studio's Gradle and CMake.
My (possibly wrong) expectation is to try and treat Android Studio Projects like Visual Studio Solutions, and Android Studio Modules like Visual Studio Projects. Given that my codebase uses multiple Projects in Visual Studio, I am trying to create multiple Modules in Android Studio -- each one with their own build.gradle and CMakeLists.txt files.
The issue is that I cannot get one section of code (AS Module) to link with the other. I am compiling these different sections as STATIC using add_library() (I plan to have one Module that creates a SHARED library, to load into Java).
I can easily get the includes to work via include_directories("../OtherModule/src/"). However, I cannot get it to link. I cannot find the .so (or similar) file to link to (via target_link_libraries() or equivalent). When I extract the .arr file from a given Module, I do not see any .so or anything.
I realize that I could simply put the entire codebase under one Module (using one build.gradle and one CMakeLists.txt -- or network of CMakeLists.txt's using add_subdirectory()). I don't know if this is fine, or if it would take more/less time to build.
I'm sure that there could be multiple ways to set this up, and it could just be a matter of preference. All research that I've done thus far has only found strictly adding native code to the same module with Java code -- doing basic JNI native bridge stuff. I haven't been able to find a single article about multiple native Modules linking together.
I'm hoping that someone with more experience with native development on Android could help me out. Thanks!
TL;DR: Simplified scenario: (Without being concerned with the JNI native bridge) I have two Modules in Android Studio, both with only native code. I would like to have each Module have its own build.gradle and CMakeLists.txt, creating its own STATIC libraries. One Module depends on the other and must set the correct include and link directories. How do?! Is this even correct (or should there ever be only one Module with native code)?
I asked a related question here. It seems to me that AS...
...does not actually link the final module-library unless it's SHARED (it does allow static 'sub-libraries' within the module); consider making the final library shared - you will have to System.loadLibrary() it specifically in Java though.
...does not allow you to install files to other places (e.g., from your native module to your Android app). I work around this by fetching the library through set_target_properties( jniwrapper PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/../libnative/build/intermediates/cmake/${BUILD_TYPE}/obj/${ANDROID_ABI}/libnative.so ) and setting BUILD_TYPE in build.gradle. Not overly elegant though.
Overall, this does not seem to be an encouraged use-case in AS...
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.
I am currently working on a Android Project where we are expected to merge our App with 2 more apps from vendors who wouldn't be sharing their code.So just wanted to know Is there any way we could just include there Source code as JAR Files in our project and then include their resources and point to them(I did do it using getResources().getIdentifier("splash", "layout", getPackageName()) But Its still not working ?? I think I have tried all possible methods so hoping you guys could help me with this.
To quote CommonsWare from this question:
Bear in mind that your packaged classes cannot reference resources (at
least not via R. syntax), and that JARs cannot package resources,
manifest entries, etc. If all you are trying to JAR up is pure Java
code (perhaps using Android APIs), then you should be fine.
Basically, you can only use JARs that contain pure java as libraries in your app, not entire other projects.
The Activities can be compiled into a jar and added to the main Android project and we need to add their project's resources into your Project. The only we could make it work is using the getResources().getIdentifier("splash", "layout", getPackageName()). Even the Widgets like TextView, Button and all those should be referred to using the getResources() method. Like, for example, If you want to perform a action on particular button then we need to identify them by getResources().getIdentifier("Button" /*id in the XML File*/, "id"/*type*/, getPackageName()).
One more thing: you need to specify all the Activities in your Main Android Project's AndroidManifest.xml file with their package name. I hope this solves something.
In order to support faster build times, the r16 tools are creating their own jar files inside of Android Library Projects. You can use this feature to solve this issue. If a vendor would like to release their Android Library Project but without source code, they can make a copy of that Android Library Project that contains everything except for the source code tree. Next, include the jar file from the original Android Library Porject (the one that the r16 tools built.) This will allow you to have a component you can distribute that does not require source code. The consumer of this new Android Library Project will need to manually add any necessary meta data to their own project's AndroidManifest.xml file as needed (Activities, Providers, Permissions, etc).
I'm developing a software layer that I would like to reuse several time for building my Android applications. Basically I want that, once installed, the software layer any other apps can use it (like a system library).
I was wondering what is the best solution for doing this, when I found that recently Android supports library projects (http://developer.android.com/guide/developing/projects/projects-eclipse.html#SettingUpLibraryProject).
So I decided to create my software layer as a library project, making the code it contains re-usable by the other applications I want to realize.
My software layer depends on a set of external jar, which are correctly located in the lib folder of the library project.
The problem is that when I create a new project referencing the library project I'm not able to see the classes defined into the external jars of the library project: i.e. it seems that they are not part of the classpath.
So when referring to a library project is possible to re-use only the source code defined there? If my library project have some other libraries I have to import these libraries also in the other ones (I want to avoid this!)?
I'm also interested to know if there are other ways for doing this, but searching around I haven't found other ways for realizing Android libraries/shared code.
Thanks.
Android library projects definitely incorporate any JARs you have in the library project's libs/ directory. However, if you are using Eclipse, you probably have to somehow manually add those to your build path of the host project (the one reusing the library).
Ok I finally figured out that for solving this is sufficient to add the jars to the host project build-path (no need to re-import them, you can just choose the path from the library project). However it is weird that they are not automatically exported in the host project classpath.