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Dagger 2.2 component builder module method deprecated

I started using dagger 2.2 and the module methods in the Component builder are deprecated.
This is my Application component :
#Component(modules = ApplicationModule.class)
public interface ApplicationComponent {
void inject(Application application);
}
And the Application module:
#Module
public class ApplicationModule {
Application application;
public ApplicationModule(Application application) {
this.application = application;
}
#Provides
#Singleton
Application providesApplication() {
return application;
}
}
Here is the generated class:
#Generated(
value = "dagger.internal.codegen.ComponentProcessor",
comments = "https://google.github.io/dagger"
)
public final class DaggerApplicationComponent implements ApplicationComponent {
private DaggerApplicationComponent(Builder builder) {
assert builder != null;
}
public static Builder builder() {
return new Builder();
}
public static ApplicationComponent create() {
return builder().build();
}
#Override
public void inject(Application application) {
MembersInjectors.<Application>noOp().injectMembers(application);
}
public static final class Builder {
private Builder() {}
public ApplicationComponent build() {
return new DaggerApplicationComponent(this);
}
/**
* #deprecated This module is declared, but an instance is not used in the component. This method is a no-op. For more, see https://google.github.io/dagger/unused-modules.
*/
#Deprecated
public Builder applicationModule(ApplicationModule applicationModule) {
Preconditions.checkNotNull(applicationModule);
return this;
}
}
}
How do I initialize the component if not with the ComponentBuilder?

You should read the description of why it is deprecated. If you are using an IDE like IntelliJ or Android Studio you can just select the method and hit Control + Q on Windows to read the Javadoc including the deprecation notice.
The Javadoc reads:
#deprecated This module is declared, but an instance is not used in the component. This method is a no-op. For more, see https://google.github.io/dagger/unused-modules.
And from this link you can see:
When the Dagger processor generates components, it only requires instances of modules and component dependencies that are explicitly needed to supply requests for a binding.
If all of a module’s methods that are used in the component are static, Dagger does not need an instance of that module at all. Dagger can invoke the static methods directly without a module.
If a module provides no bindings for a Component, no instance of that module is necessary to construct the graph.
It is safe to say that you can just ignore the deprecation. It is intended to notify you of unused methods and modules. As soon as you actually require / use Application somewhere in your subgraph the module is going to be needed, and the deprecation warning will go away.

It show deprecated because you are not using Component and module in your application by
#Inject
SomeObjectFromModule mSomeObject
if you are not injecting dependencies in your applications there is no use of initialising your component so dagger look for at least one usage
once you add these lines in any classes you want to inject views and then clean build and rebuild the project and your deprecation will be solved

It showing error when my Module have no #Provides method or the object that provide by Dagger is not used in app.
Example to remove deprecated module
Module
#Module
public class SecondActivityModule {
#Provides
Book provideBookTest() {
return new Book();
}
}
Activity
public class SecondActivity extends AppCompatActivity {
#Inject
Book test;
...
}
OR in Component
#Component(modules = SecondModule.class)
public interface SecondComponent {
void inject(SecondActivity activity);
Book getBookTest();
}

I have the same problem with host and I just want everyone has deprecated issue on Generated component builder class should check two things to save time:
1/ Correct dagger syntax for module, component also check carefully where you inject.
2/ Must have injection object (inject annotation and its object) in place you want to inject or else the dagger compiler cannot see where to use your module so some method will be deprecated.Just inject at least one module's provides to your injection place and re-compile the code, you won't have that issue anymore :)

you will get module method deprecated if you declare void inject(AppCompactActivity activity); in component class. instead of you have to use tight coupling like following void inject(MainActivity activity);and rebuild your project you will see, there is no deprecate method in module class

how can I inject a dependency in a method?

I'm a beginner with dependency injection.. specifically Dagger 2. I'm trying to figure out if/how I can do something like this:
#Inject
public void someMethodName(int someInteger, SomeObject dependency){
// do something with the dependency.
}
Or do I need to put that dependency in as a class var? any help with this would be greatly appreciated. also in this case the variable someInteger is not a dependency, but is being added by the caller... does that matter?
can I call it like this:
this.someMethodName(5);
android studio does not like the above calling method (I'm assuming because I'm doing something wrong)

You need to create component which is annotated by #Component.
The Component accepts module which provides dependencies.
Every component's name that you create starts with Dagger prefix, e.g. for MyComponent.
Let's look at the following example:
#Singleton
#Component(modules = DemoApplicationModule.class)
public interface ApplicationComponent {
void inject(DemoApplication application);
}
We created ApplicationComponent with single injection method. What we're saying is that we want to inject certain dependencies in DemoApplication.
Moreover, in the #Component annotations we specify module with provision methods.
This is like our module looks like:
#Module
public class DemoApplicationModule {
private final Application application;
public DemoApplicationModule(Application application) {
this.application = application;
}
#Provides #Singleton SomeIntegerHandler provideIntegerHandler() {
return new MySomeIntegerHandlerImpl();
}
}
What we're saying by creating DemoApplicationModule is that the module can provide desired dependencies in the injection place specified by our Component.
public class DemoApplication extends Application {
private ApplicationComponent applicationComponent;
#Inject SomeIntegerHandler handler;
#Override public void onCreate() {
super.onCreate();
applicationComponent = DaggerApplicationComponent.builder()
.demoApplicationModule(new DemoApplicationModule(this))
.build();
applicationComponent.inject(this);
handler.someMethodName(5);
}
}
See documentation what you kind of dependencies you can obtain. Additionally to obtaining just raw instance you can obtain Provider, Factory or Lazy instance.
http://google.github.io/dagger/api/latest/dagger/Component.html
You can also create scoped dependencis, the lifecycles of which depend on the lifecycle of injection places, like Activities or Fragments.
Hope I gave you the basic notion of what Dagger is.

YOU CAN USE SOME INTERFACE
public interface myDependence{
int myFunction(int value);
}
NOW IMPLEMENT IN YOU CLASS
public myClass implements MyDependence{
#Override
int myFunction(int value){
// do something
}
}

What does #Module means in dagger for android?

I have read many blogs but still i am not able to figure out #Module annotation functioning in dagger.
#Inject i got that it provides dependency injection at runtime. But what does #Module does.
since the object graph is also built on module.
For ex i.e i have this snippet of code from https://github.com/AndroidBootstrap/android-bootstrap.
#Module(
complete = false,
injects = {
BootstrapApplication.class,
BootstrapAuthenticatorActivity.class,
MainActivity.class,
BootstrapTimerActivity.class,
}
)
public class BootstrapModule {
}
so what does it basically does. since i am also trying to build one application using dagger as dependency injection for android.But since I am not able to get #Module concept clearly I am just stuck.
Can anyone please help me out with some basic example or concept. I think this will be helpful for all who is using dagger.

If you have a look to the docs for the annotation, a #Module annotated class defines a class that contributes to the dagger object graph. In the Spring framework for example, the equivalent would be the #Configuration anntotation. It defines a configuration point for your object graph, where you declare which objects you want to be available for injection and their scopes.
As a simple example, let's say we want a singleton object to be used by any Activity in the app. It has to be created in the module:
#dagger.Module(injects = {MyActivity.class})
public class Module {
#Provides
#Singleton
public MySinletonBean provideMySingleton() {
return new MySinletonBean();
}
}
This will create a MySingleton object which can be injected in MyActivity. This is a very basic example, but we can perform other actions in the graph there, like using dependencies in the constructors:
#dagger.Module(injects = {MyActivity.class})
public class Module {
private DependencyBean dependency = new DependencyBean();
#Provides
#Singleton
public MySinletonBean provideMySingleton() {
return new MySinletonBean(dependency);
}
#Provides
#Singleton
public MySinletonBean provideMyOtherSingleton() {
return new MyOtherSinletonBean(dependency);
}
}
Then, in MyActivity we need to access the graph for the application in the onCreate method:
#Inject
MySingletonBean singleton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.my_activity);
((MyApplication) getApplication()).getGraph().inject(this);
}
So, who does create the object graph here? The MyApplication class does it when your application starts (don't forger to add it in your androidManifest.xml):
public class MyApplication extends Application {
private ObjectGraph graph;
public ObjectGraph getGraph() {
return graph;
}
#Override
public void onCreate() {
super.onCreate();
graph = ObjectGraph.create(new Module(this));
graph.inject(this);
}
}
So the execution flow in a dagger app would be:
The android app starts and the MyApplication class builds the graph, parsing the #Module annotated classes and keeping an instance of it.
Then, the classes declared in the module can access its objects just injecting themselves in the object graph. Gradle then will evaluate their #Inject annotations and perform the dependency injections.

I guess Annotation Processing Tool requires that to generate code at the compile time.
This makes it Dagger can provide validation at compile time and not only at runtime.

Dagger not initializing injected field in Android

Started introducing Dagger into my App and I'm having problems getting a very basic field initialized. Here's a reduced version of my code:
#Inject public DaggerUtils daggerUtils;
public class AppState extends Application {
#Override
public void onCreate() {
super.onCreate();
// Set up Dagger
AppModule appModule = new AppModule();
mObjectGraph.create(appModule);
daggerUtils.print();
}
}
Module used:
#Module(
injects = { AppState.class}
)
public class AppModule {
// This provides method is commented out because from what I can understand from the Dagger documentation
// Dagger should automatically take care of calling the constructor I have provided
// with the #Inject annotation. I have tried commenting this out as well and it still
// fails.
//#Provides
//DaggerUtils provideDaggerUtils() {
// return new DaggerUtils();
//}
}
Basic util class:
public class DaggerUtils {
#Inject
public DaggerUtils() {
}
public void print(){
Logger.e("Dagger", "printed instantiated");
}
}
So from what I understand because I have the #Inject annotation before the DaggerUtils constructor and the #Inject annotation before the DaggerUtils instance I'm using in my AppState class, Dagger should take care of initializing the DaggerUtils instance without me having to call the constructor. However it keeps giving me an NullPointerException when I try to call daggerUtils.print() (Line 12 in AppState class). Why is dagger not initializing DaggerUtils? I feel like I'm missing something very basic here. I've also tried using the #Provides method commented out in the AppModule to provide an instantiated DaggerUtils but it still isn't working.

I had same problem this evening.
For every class, who needs injection you must call:
mObjectGraph.create(appModule).inject(this);
That is usefull to create inject method in Application.
public void inject(Object object) {
mObjectGraph.inject(object);
}

Dagger not injecting Android Annotations class

Alright, I'm having an issue trying to mix frameworks.
So, I have a #SharedPref annotated class that should generate a Shared Preferences manager from Android Annotations. The class looks a bit something like this:
DownloadPrefs.java
#SharedPref(value= SharedPref.Scope.UNIQUE)
public interface DownloadPrefs {
#DefaultBoolean(false)
boolean hasEnabledDownload();
#DefaultBoolean(false)
boolean showedDownloadDialog();
#DefaultLong(0)
long downloadRefreshedOn();
}
Now, I'd like to inject the resulting class (which will be DownloadPrefs_) into a Fragment to make use of it. The fragment has had working injection before adding the new module, so I'm only going to write here what I added:
Fragment.java
#Inject DownloadPrefs_ downloadPrefs;
Now, since the actual DownloadPrefs_ class is generated at runtime, it would make the most sense to create an #Provides annotation for it, since I can't mark a constructor as injected. Nor does the DownloadPrefs_ have a no-arg constructor. The module I'm using then receives the new #Provides:
DownloaderModule.java
#Provides //#Singleton // Does not work with/out #Singleton
DownloadPrefs_ provideDownloadPrefs() {
return new DownloadPrefs_(MinimalBible.getApplication());
}
To be technical about it, the DownloadPrefs_ constructor that gets generated by Android Annotations expects a Context passed to it, I would have guessed that the Application context would be suitable. Otherwise, I'm not sure how I could possibly get access to the Activity context. Or whether that would actually break the ObjectGraph.
However, when I go to run the actual injection, I get the following message:
Caused by: java.lang.IllegalStateException: Errors creating object graph:
org.bspeice.minimalbible.activities.downloader.DownloadPrefs_ has no injectable members. Do you want to add an injectable constructor? required by class org.bspeice.minimalbible.activities.downloader.BookListFragment
Any clue on what's going on? It doesn't seem like the questions asking about "no injectable members" on other SO questions answered my case. I had a working app before adding the code above.
UPDATE: After doing some double-checking, I came across the following weird behavior. If I copy out the pre-built Android Annotations class, rename it, and inject that, everything works. Additionally, I can verify that the original built Android Annotations class (the DownloadPrefs_.java) does in fact exist in the .dex, so Dagger should have no reason to not be able to find it. Everything is doing a debug build, so I can't imagine ProGuard is messing anything up.
At this point, I'm going to create a minimal project to demonstrate the error, and file an issue with Dagger. In the mean time, just need to rewrite the Prefs class until I can get this sorted out.
UPDATE 5/12/2014
Here are the modules responsible for injection:
MinimalBibleModules.java
#Module(
injects = {
MinimalBible.class
},
includes = {
ActivityModules.class
}
)
public class MinimalBibleModules {
}
ActivityModules.java
#Module(
includes = {
ActivityDownloaderModule.class
}
)
public class ActivityModules {
}
ActivityDownloaderModule.java
#Module(
injects = {
BookListFragment.class,
DownloadManager.class,
BookRefreshTask.class
}
)
public class ActivityDownloaderModule {
#Provides #Singleton
DownloadManager provideDownloadManager() {
return new DownloadManager();
}
#Provides
EventBus provideBus() {
return new EventBus();
}
#Provides //#Singleton
DownloadPrefs_ provideDownloadPrefs() {
return new DownloadPrefs_(MinimalBible.getApplication());
}
}
Also, how the graph gets created:
MinimalBible.java
public class MinimalBible extends Application {
private ObjectGraph graph;
private static MinimalBible instance;
public MinimalBible() {
instance = this;
}
#Override
public void onCreate() {
graph = ObjectGraph.create(new MinimalBibleModules());
graph.inject(this);
}

There are two parts here. First, how you get access to the Context. You can do static things as you are, though that's not advisable. Generally, you should configure your graph with a stateful module that carries the context, like this:
#Module
class ApplicationModule {
private final Application application;
public ApplicationModule(Application app) {
this.application = app;
}
// you can mark this singleton, but it's minor overhead
// and the fact that you have a single instance stored
// means it's semantically equivalent. But for clarity
// it's sometimes good to make the point.
#Provides
#Singleton
Application application() {
return application;
}
// optionally: bind it as a Context with a qualifier.
// note: never bind Context without a qualifier annotation
// as Activity and Application are both Context subtypes.
#Provides
#Singleton
#PerApplication
Context appContext(Application app) {
// Doing this instead of returning this.application is
// semantically equivalent but links #PerApplication Context
// to Application, so in graph analysis and error reporting
// the link is clearer. That's a personal choice.
return app;
}
}
At any rate, you then when you create the graph:
Application appInstance = ...;
ObjectGraph appGraph = ObjectGraph.create(
MyAppModule.class,
new ApplicationModule(appInstance));
The Application is then seeded into the graph and can be depended-upon by other types that declare it as a dependency.