Develop Reference

How can I see dependency updates in build.gradle when using variables?

Android studio will show you if there is a newer version of a library when the version number is hard coded. But if you use variables, this seems to short circuit that functionality. Is there any way to get it back? I want to see available updates in build.gradle without having to Inspect the project.

Gradle 6 offers a new way to recommend and share versions between projects called platforms. This allows you to specify a set of dependency versions to share across projects without using variables.
You can use the Java Platform Plug-in to create a platform; a special kind of project that only contains a list of dependencies that work together. I haven't tried this, but hopefully Android studio will alert you if any of these versions are out of date since you'll be using hard coded version numbers.
You can then reference your platform in your other projects using the platform keyword and load all the other dependencies without versions
dependencies {
// get recommended versions from the platform project
api(platform(project(":platform")))
// no version required
api("commons-httpclient:commons-httpclient")
}

Whorlwind and RxJava2

I have a question regrading RxJava2 support in WhorlWind.
I am converting a project which uses Whorlwind from Rx1 -> Rx2. My current Whorlwind version in my root project gradle is 1.0.1, which according to their github CHANGELOG.MD is the only version.
https://github.com/square/whorlwind/commit/769ad313154df46ce07638dc79bd46ae14e5fbfb
As you can see, the commit above has made the changes to support rxjava2 however I am not able to find a version number to update in my gradle. There must be some key concept I'm missing because how I understand it, the Whorlwind library on my machine will remain at the RxJava1 build until I update the gradle to bring in some new Whorlwind library.
Thanks

I ran into the same issue with that library, what I did to move forward was to use the library the same way that the sample app that they have uses it. By adding the library to your project and referencing the library from there.
See their build.gradle here:
https://github.com/square/whorlwind/blob/master/whorlwind-sample/build.gradle

https://github.com/square/whorlwind/commit/47961437c611abc4ec88c900cdb6621ef6662b1c
In the gradle.properties, Square lists a snapshot of a newer version that supports Rx2. I'm not sure why they don't list it in the ChangeLog or ReadMe

Setting and getting the version of the Android Library

I have created a library in Android Studio and wanted to give it to someone for testing.Besides maintaining it in the svn I am providing the version of the library hardcoded in the Library code which I keep on changing everytime I build and send it for testing to track the record.
The code is as below :
defaultConfig {
..
..
..
versionName "0.00.0012"
}
and then getting the version of the Library as BuildConfig.VERSION_NAME
Does the App version will change in the AndroidManifest.xml as well automatically?
is there any other way of managing the various lib versions?
android:versionName="not the same version"

Does the App version will change in the AndroidManifest.xml as well automatically?
No, library version will not influence application's version in any way. Both are separate.
is there any other way of managing the various lib versions?
What you do lets the consumer check the version of the library in code, which is fine. If you want to actually distribute new versions of the library then you'd probably want to use a maven repository - either local or a remote one, and push your library there with given version. This is the version you then reference in compile 'com.my.library:library:1.2.3'.

Kotlin library 'classes.jar' has an unsupported format. Please update the library or the plugin

This message appears on project sync.
I've tried to clean and rebuild the project, but no success.
I'm using latest plugin version 0.12.275, "org.jetbrains.kotlin:kotlin-gradle-plugin:0.12.213" and "org.jetbrains.kotlin:kotlin-stdlib:0.12.213"
I've tried with the stable version 0.12.200 for both plugin and library, but I get the same error.
I'm using Android Studio AI-141.1972460 (canary channel).

Looks like the problem was in my *.aar lib, that was included in the project - it was compiled with an old version of Kotlin. I've upgraded the libary to the latest Kotlin version and it works now.

This issue was resolved with the updated library as mentioned by #ookami.kb
About the error message...
The "unsupported format" error comes when the ABI version number of the class files created by Kotlin does not match the expected used by the Kotlin compiler. This is no longer an issue with Kotlin 1.0 Betas since the ABI number will not change again for 1.0. But, there will be one forced recompile at 1.0 release candidate to ensure no old compiler bugs affect libraries or code and everything is rebuilt clean. Afterwards no issues such as this will exist.
Therefore if a library is not up to date with the same ABI, or hits this last "1.0 recompile" you may run into a similar error. The solution is always to find the updated library.
More about this in the Kotlin 1.0 Beta 4 announcement "What's Next" section:
After the Beta period is over, there will an RC and then 1.0.
We would really like to make sure that no code compiled with
pre-release versions of Kotlin are kept around after 1.0, so the RC
compiler will force recompilation of all the old code. We will
coordinate with library maintainers outside JetBrains to make sure
that all the widely-used libraries will be recompiled in time.
We’ll also take the opportunity to remove some legacy at this point:
remove all the deprecations that we have accumulated in the process of evolving our libraries,
remove all the deprecations from the generated code (you might not have heard of those, but they exist!),
get rid of some legacy bytecode peculiarities that were found during the beta,
move some of the stdlib code around so that the packages there have
more structure.
After that point, the only compatible changes to the
standard library are deprecations and additions (this does not include
reflection APIs). We are running an open review for the library API to
make sure we haven’t missed anything important.

This is Kotlin bug with new plugin version

Android Wear: how to share code between the wearable and handheld modules?

I am making an Android app with Wear capabilities.
I want to share some code between the wearable and handheld modules. Specifically, I want to share communication code that uses Google Play Services classes, e.g. com.google.android.gms.common.api.GoogleApiClient.
The obvious way to do this is to have a module (I called it common) and add a dependency to it in both the handheld and the wearable modules.
Since this common module uses Play Services, I need to make it depend on com.google.android.gms:play-services.
I was not sure what to put for the version number - the official documentation here says to use 5.0.77, but that does not work, as the latest SDK does not have this version anywhere, instead it comes with 5.0.89 and 5.2.08.
If I use 5.0.89, the Wearable app does not work, with this error: Google Play services out of date. Requires 5089000 but found 5077534. The version on the watch is older than the one I used to compile.
Instead of depending on com.google.android.gms:play-services the common module could depend on com.google.android.gms:play-services-wearable but then there is a conflict when building because the handheld module depends on com.google.android.gms:play-services, and these two artefacts use the same package name (com.google.android.gms), and so the gradle build fails.
What's the solution?
.
EDIT after discussing a bit and to make my question clearer.
To be able to use communication APIs in my common module I have two choices:
Make common depend on com.google.android.gms:play-services
Make common depend on com.google.android.gms:play-services-wear
⇒ Solution 1 does not work because the version available (5.0.89) for development is more recent than the one on the watch (5.0.77).
⇒ Solution 2 does not work because the handheld module already depends on com.google.android.gms:play-services, which conflicts with com.google.android.gms:play-services-wear.

I bumped into the same problem a few days ago. My shared module depended on com.google.android.gms:play-services as well, so Gradle refused to build and kept nagging at me:
Error: more than one library with package name 'com.google.android.gms
I added this line to my mobile project's gradle file and the error disappeared magically:
compile(project(':sharedModule')) {
transitive = false
}

Take a look here: https://github.com/tajchert/SWear_Weather
I had created common project that is shared between mobile and wear, and contains my constants. Remember to set there dummy manifest file and:
apply plugin: 'com.android.library' in build.gradle file.
I had also encountered problem with play-services version - I had solved it by using
compile 'com.google.android.gms:play-services-wearable:+'
compile 'com.google.android.support:wearable:+'
instead of specifying particular version - to be honest it should be separete question - as it is out of scope of previous (sharing code between projects).
It is possible to need invalidate cache/restart after changing - you can/should remove build paths in your projects to get rid of all other versions.