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Dependency injection for Android NDK?

I've been working on a writing a game for Android. Until now I've been using Java instead of the NDK, but I've decided to port my code to C++ (for performance, memory management and industry standards reasons).
Porting my application shouldn't be a problem (I've written my fair share of C++ applications), but I've been using RoboGuice as a dependency injection framework because otherwise my object graph would become too complex rather quickly.
I've been looking around, but I haven't found any resources about using a dependency injection framework in combination with the Android NDK.
Can someone tell me if there any such franeworks available. If so, which one would you recommend?

If you have a C++11 compiler for Android you could use several frameworks (I wrote Infectorpp) but there are others available. You should note that DI is quite limited in C++ due to the lack of reflection so you should make some compromises as not everything you did in RoboGuice would still be possible.
By doing a quick search seems that C++11 is possible on Android. I don't have an Android device and still not needed to emulate it, but if you have any feedback it will be wellcome (private message here or support ticket on google code is enough), the library is headers only so no special build stuff is required for it, apart enabling c++11 on your compiler wich is just one extra option by command line. If that will works good on Android then it will be definitely good also for PC. (Do not misunderstand please, I'm using it heavily, but seems very few people is interested in DI in C++ and so I get very little feedback)
There was also a nice framework cpp-resolver: a little awkard to use because you explicitly register factory functions for injecting ALL parameters, but very scalable, especially for server applications.. (decouple object lifetime management and works with plain old C++).
The most complete framework is probably wallaroo
If you search something really easy to use Infectorpp is a good choice
If you need control over lifetime (mostly servers): Cpp-resolver is perfect
If you need exotic features and configuration files: wallaroo
As side note, run-time configuration is possible also with frameworks that do not explicitly support it:
You just need a Factory that istantiate a different type based on a configuration file you could read through a class that you add as dependency to factories (Probably you don't need to know that since you were already using DI frameworks, but still good to know for occasional readers)

Dagger and Butter Knife vs. Android Annotations

I am evaluating Dependency Injection (DI) frameworks for an Android app. The top contenders are: Dagger (with Butter Knife) and Android Annotations. I understand that Dagger and ButterKnife are from the same source- square and they complement each other. Here're are the key matrices that I am looking for:
Ease of use (our build is based on Gradle and we use Android Studio IDE)
Testing support (we use Robotium for functional testing and RoboLectric for unit testing)
Performance (DI frameworks use reflection, which one is faster?)

AndroidAnnotations
uses compile time annotation processing. It generates a sub class with an underscore apppended to the original name (MyActivity_ generated from MyActivity). So to have it work you always have to use the generated class for references instead of your original class.
It has a very rich feature set, see the list of available annotations.
Butterknife
uses also compile time annotation processing, but it generates finder classes which are used by a central class (ButterKnife). This means that you can use your original class for referencing, but you have to call the injection manually. A copy from the ButterKnife introduction:
#Override public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.simple_activity);
ButterKnife.inject(this);
// TODO Use "injected" views...
}
The feature set is not so rich, ButterKnife supports view injection (AndroidAnnotations equivalent would be #ViewByIdand #ViewsById) and some event binding (for a complete list see the namespace directory here, just count the OnXXX event annotations).
Dagger
is a DI implementation for Android, similar to Guice. It also uses compile time annotation processing and generates object graphs which you use for manually injection. You distinguish between application object graph and scoped object graphs for injecting e.g. in activities. Here you see an Application.onCreate example:
#Override public void onCreate() {
super.onCreate();
objectGraph = ObjectGraph.create(getModules().toArray());
objectGraph.inject(this);
// use injected classes
}
I found it is harder to start with dagger, but this might be only my experience. However see some videos here for a better start: 1, 2
From the feature set point of view I would say that Dagger implements functionalities which could be compared to AndroidAnnotation's #EBean and #Bean functionality.
Summary
If you are comparing ease of use, testing support and performance I can't find much difference between using AndroidAnnotation and ButterKnife+Dagger. Differences are in the programming model (use classes with _ instead of using the original ones and call the injection manually) and in the feature set.
AndroidAnnotation gives you a full list of functionalities, but ties you to certain libraries. For example if you use it's rest api you have to use Spring Android. You also have annotations for features like OrmLite (#OrmLiteDao) regardless if you use OrmLite or not.
At the end it is a matter of taste, at least in my opinion.

Here is the Nice article in Dzone blog.
We to need to compare the features of each, such as :
Minimum Jars required
ActionBarSherlock compatibility
Injection for click listeners
POJO injection
Performance
Only Pojo Injection missing in butterknife! So looks like Butterknife is the winner!
Source

Google does ask specifically not to use dependency injection.
But by reading their request they seem to be referring more to the Guice and reflection based DI library's. Libraries such as android annotation use no reflection instead employing compile time generated code, while butterknife and dagger uses a small amount of reflection optimised for android but are supposedly slightly more powerful than android annotation. It really depends on the project and how much of a performance hit you are willing to take. In my opinion just using butterknife is sufficient to speed up code development by itself. If you need slightly more use android annotation and lastly if you are willing to take a slight performance hit due to reflection the best option without absolutely destroying performance with a powerhouse Guice based reflection use dagger + butterknife.

You should give a try at Toothpick.
Toothpick is (per the README):
pure java
fast, it doesn't use reflection but annotation processing
simple, flexible, extensible & powerful, robust & tested
thread safe
documented & Open Source
scope safe : it enforces leak free apps
test oriented : it makes tests easier
it works very well with Android or any other context based framework (such as web containers)
It can even be faster than Dagger 2 in most cases, and it's much simpler.
Note: Yes, I am one of the authors.

Use Android Annotations or Butterknife to ease your coding. But don't go for Roboguice! Roboguice forces your activies, fragments to extend to roboguice classes. Not fun, at all!
Dagger 2 is a much better option. You can use it along with Android Annotations if you'd like. I would just use Android Annotations for a simple app, but these days is good to work more with Dagger.

Seems like Google chooses dagger, as they are developing it jointly with Square, who created it.
Concerning Butterknife and Dagger themselves, there is the SO question difference-between-dagger-and-butterknife-android which clarifies how they complement each other.

The reddit-thread mentioned by #ChrLipp has someone who used all three on the same project, speaks highly of dagger+butterknife but also gives AndroidAnnotations its place:
For dependency injection, butterknife is used for Views, Dagger is
used for all objects and is highly recommended and Android Annotations
creates more of a framework for developing Android instead of
injecting objects into your classes so each library are quite
different from each other. Dagger is equivalent to Guice but is much
much faster. Dagger is more powerful then ButterKnife and Android
Annotations as it injects all objects rather than ButterKnife and
Android Annotations which only inject a certain set of objects.
Dagger can be a pain to setup and configure but is well worth it once
you have it done. But then again, because these are all quite
different from each other, it all depends on what your needs are for
the project.
Also, speaking of each one being quite different, in your project you
can use ButterKnife, Android Annotations and Dagger all in the same
project if you really want to. They each have the same idea but do
something different so you could use them all.

Eventually if you use one of the three, you'll have a hard time transitioning to Android's databinding. That's what's fastest if you need to consider performance:
https://developer.android.com/tools/data-binding/guide.html

Does "Avoid dependency injection frameworks" in the Android Memory Guide apply to Dagger as well?

So I have come across this best practices on Android articles on memory performance.
http://developer.android.com/training/articles/memory.html
They said
Avoid dependency injection frameworks
Using a dependency injection framework such as Guice or RoboGuice may
be attractive because they can simplify the code you write and provide
an adaptive environment that's useful for testing and other
configuration changes. However, these frameworks tend to perform a lot
of process initialization by scanning your code for annotations, which
can require significant amounts of your code to be mapped into RAM
even though you don't need it. These mapped pages are allocated into
clean memory so Android can drop them, but that won't happen until the
pages have been left in memory for a long period of time.
But what about Dagger which they claim to be fast. Not sure which one should I go for?

This recommendation does not apply equally to all dependency injection frameworks.
..frameworks [that work like Guice] tend to perform a lot of process initialization by scanning your code for annotations, which can require significant amounts of your code to be mapped into RAM even though you don't need it..
Thus, if using a DI/IoC framework that doesn't scan for said [run-time] annotations, implying the [excessive] use of reflection, then this reason doesn't apply. While Dagger does use annotations these are used differently than by Guice1 and avoid the problem stated.
Since Dagger was written as "A fast dependency injector for Android and Java", the authors have designed it for this purpose and believe that it is suitable for such a target - go ahead, give it a try.
1 Dagger uses compile-time annotations (well, mostly) instead of relying on run-time annotations and reflection; it is the run-time annotation scanning and reflection that causes the issue the memory guide was warning about.

The Android team has recently updated their recommendation to suggest developers use Dagger 2.
The previous recommendation was based on the high cost of reflection. Since Dagger 2 no longer uses reflection - Dagger 1 did - they believe it "can be used in Android apps without needless runtime cost or memory usage".
(Disclaimer: I'm the Dagger 2 team manager.)

The creator of Dagger, #JakeWharton, also wrote a simpler view "injection" framework called Butterknife
because all the RoboGuice converts were complaining about lack of
"view injection" with Dagger.
You use it like this:
class ExampleActivity extends Activity {
#InjectView(R.id.title) TextView title;
#InjectView(R.id.subtitle) TextView subtitle;
#InjectView(R.id.footer) TextView footer;
#Override public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.simple_activity);
ButterKnife.inject(this);
// TODO Use "injected" views...
}
}

Dependency injection best practices articles were recently added to Android developer official website. In these articles developers are encouraged to use Dagger 2 as a primary DI library for project medium (4-7 screens) and large (8+ screens) apps.
Dagger facilitates using DI in your app by creating and managing the graph of dependencies for you. It provides fully static and compile-time dependencies addressing many of the development and performance issues of reflection-based solutions such as Guice.

What are the specific benefits of using DI on Android?

What are the specific benefits or advantages of using a dependency injection framework for Android, like Dagger, Transfuse or RoboGuice?
For example, what kind of apps would benefit the most from using DI? is there more of a performance advantage, or is it more on the ease of extending an app, or even more about making it testable?
One of the reasons for asking this is to gauge if an app I'm developing would actually benefit from it or not much. Since I intend the app to be serious at some point, testability and ease of extension would be great, even if costly to use (more time to setup, learning curve, etc) for the first versions.
Thanks!

For example, what kind of apps would benefit the most from using DI?
Dependency injection (as a pattern not a library) benefits almost all code.
It promotes designing modular components which expose only the necessary APIs required to perform a specific action. When you are forced to break up pieces of your applications you have to consider how much implementation detail to expose, how the API behaves, and the visibility of classes and methods.
It promotes logical abstractions of components (think: interfaces and their implementations). You certainly don't have to do this, but it ends up occurring organically anyway the more you DI things.
It facilitates testability by creating a single point of type consumption through which a class obtains something it needs. Need to swap out a Foo for a TestFoo? No problem.
Is there more of a performance advantage?
No. The dependency injection libraries exist solely to reduce boilerplate around the pattern and increase the declarative ability to request dependencies.
Is it more on the ease of extending an app?
Absolutely. While I would never recommend using Guice (or RoboGuice) in an Android application, the introductory talk to Guice from Google I/O is a fantastic introduction to why dependency injection is important in this regard.
Even more about making it testable?
Yes and no. This is a happy side-effect of proper abstraction and modularization. Testing is a great thing so the fact that dependency injection offers an ease into it is also great.
I gave a talk about Dagger in the context of Android recently which you can watch* or view the slides. The talk starts out with dependency injection as a pattern and then moves into how Dagger reduces the boilerplate and enables some pretty cool features as well.
I also made a fairly advanced sample application which leverages Dagger for complex injection use-cases that might also be worth checking out.
*The talk is currently not free, but will become so at some point in the next 10 months.

Does it make sense to use Guice for Android

I'm debating using guice in an android project that is quite complex and has a lot of business logic. Guice seems like a good fit, but whenever I start reading deeper into it, it starts to look more complicated than it needs to be.
One thing I don't understand is: if Guice is so great and the best way to write java code, how come there is so little Android code that uses Guice... and why didn't Google use guice internally for Android?

Guice totally makes sense to be used and in fact is used in a whole bunch of applications. The extension RoboGuice adds some niceties for Android that makes it super productive to use.
In fact I can not imagine writing an Android app without it. Too painful.
Check out the links to apps using Roboguice on the website (e.g. Google Docs, OpenTable...). Also other apps like the Square app are known to use Guice directly.
It totally makes sense .. go do it!
Together with Robolectric it will also make your testing efforts easier.
PS: I am a committer on RoboGuice so I am partial ;-)
PPS - June 2013: Recent developments have given rise to other annotation/dependency injection based frameworks that do most of the work at build time and therefore avoid the performance hit of the runtime reflection (that is slow on Android) and are therefore more suitable for performance critical work - check out Dagger and AndroidAnnotations if you are interested in that.

Actually google discourages using Guice or RoboGuice in android applications due to memory overhead.
Source:
http://developer.android.com/training/articles/memory.html#DependencyInjection
5.11.2014 Edit:
There is a dedicated fast dependency injection library for android. I can see more and more people using it:
http://square.github.io/dagger/
13.04.2015 Edit:
Google released its own version of dagger, which does not use reflection in runtime:
http://google.github.io/dagger/

You know there is RoboGuice? It's Guice for Android.

The problem with demonstrating the strengths of a dependency injection framework is that it isn't possible to achieve it with a simple Hello World application. These frameworks show their value only in big systems with a lot of complexity. Also, they have a somehow steep learning curve.
Therefore it is quite normal that you can't find enough tutorials - open source projects that use Guice. This will be most often used in enterprise applications that do not get published.
As why Google doesn't use Guice, Guice doesn't fit everywhere. It adds a perfomance overhead and it doesn't make sense to use it in places, where it isn't needed.