Dagger just got better

New features in the latest Dagger dependency injection library.

Transcript

1. Dagger just got better DINO BIKIĆ
2. DAGGER
4. “Dagger is a fully static, compile-time dependency injection framework for both Java and Android.”
5. “Dagger is a fully static, compile-time dependency injection framework for both Java and Android.”
6. WHAT’S DEPENDENCY INJECTON?
7. BestActivityEver.java
8. BestActivityEver.java
9. BestActivityEver.java
10. BestActivityEver.java
11. BestActivityEver.java BestObjectEver.java
12. BestActivityEver.java BestObjectEver.java
13. BestActivityEver.java BestObjectEver.java EvenBetterObject.java GodObject.java MasterObject.java
14. HOW IT’S DONE?
15. dependencies { compile 'com.google.dagger:dagger-android:2.x' compile 'com.google.dagger:dagger-android-support:2.x' annotationProcessor 'com.google.dagger:dagger-android-processor:2.x' }
16. public class BestActivityEver extends Activity { @Inject BestObjectEver bestObjectEver; }
17. @Provides BestObjectEver bestObjectEver() { return new BestObjectEver(); }
18. @Module public class BestModule { @Provides BestObjectEver bestObjectEver() { return new BestObjectEver(); } }
19. @Module public class BestModule { @Provides BestObjectEver bestObjectEver() { return new BestObjectEver(); } @Provides MasterObject masterObject() { return new MasterObject(); } @Provides GodObject godObject() { return new GodObject(); } }
20. @Component(modules = BestModule.class) interface BestComponent { }
21. @Component(modules = BestModule.class) interface BestComponent { BestClassEver instantiate(); }
22. public class BestAppEver extends Application { static BestComponent bestComponent; }
23. public class BestAppEver extends Application { static BestComponent bestComponent; public void onCreate() { super.onCreate(); } }
24. public class BestAppEver extends Application { static BestComponent bestComponent; public void onCreate() { super.onCreate(); bestComponent = DaggerBestComponentEver.create(); } }
25. public class BestActivityEver extends Activity { @Inject BestObjectEver bestObjectEver; }
26. public class BestActivityEver extends Activity { @Inject BestObjectEver bestObjectEver; public void onCreate() { super.onCreate(); BestAppEve.bestComponent } }
27. public class BestActivityEver extends Activity { @Inject BestObjectEver bestObjectEver; public void onCreate() { super.onCreate(); BestAppEve.bestComponent.instantiate() } }
28. public class BestActivityEver extends Activity { @Inject BestObjectEver bestObjectEver; public void onCreate() { super.onCreate(); BestAppEve.bestComponent.instantiate() .inject(BestActivityEver.this); } }
29. 01 WHY IS DAGGER BEING USED?
30. 1 functionality = 1 implementation
31. Unit tests
32. Code generation
33. 02 DAGGER FUNCTIONALITIES
34. 01 SINGLETONS
35. @Module public class MoshiModule { @Provides public Moshi converter() { return MoshiUtils.moshi(); } }
36. @Module public class MoshiModule { @Provides @Singleton public Moshi converter() { return MoshiUtils.moshi(); } }
37. 02 SCOPES
39. 03 SUBCOMPONENTS
40. “ Components that inherit and extend the object graph of a parent component.”
41. 03 QUALIFIERS
42. @Module public class SchedulersModule { @Provides public Scheduler main() { return AndroidSchedulers.mainThread(); } @Provides public Scheduler io() { return Schedulers.io(); } }
43. @Module public class SchedulersModule { @Provides @MainThread public Scheduler main() { return AndroidSchedulers.mainThread(); } @Provides @Io public Scheduler io() { return Schedulers.io(); } }
44. 03 NEW FUNCTIONALITIES
45. 01 NEW ANDROID INJECTOR
46. App component
47. @Component(modules = {}) public interface AppComponent { }
48. @Component(modules = { AndroidInjectionModule.class }) public interface AppComponent { }
49. @Component(modules = { AndroidInjectionModule.class, AppModule.class }) public interface AppComponent { }
50. @Component(modules = { AndroidInjectionModule.class, AppModule.class, ActivityBuilder.class}) public interface AppComponent { }
51. @Component(modules = { AndroidInjectionModule.class, AppModule.class, ActivityBuilder.class}) public interface AppComponent { @Component.Builder interface Builder { } }
52. @Component(modules = { AndroidInjectionModule.class, AppModule.class, ActivityBuilder.class}) public interface AppComponent { @Component.Builder interface Builder { @BindsInstance Builder application(Application application); } }
53. @Component(modules = { AndroidInjectionModule.class, AppModule.class, ActivityBuilder.class}) public interface AppComponent { @Component.Builder interface Builder { @BindsInstance Builder application(Application application); AppComponent build(); } }
54. @Component(modules = { AndroidInjectionModule.class, AppModule.class, ActivityBuilder.class}) public interface AppComponent { @Component.Builder interface Builder { @BindsInstance Builder application(Application application); AppComponent build(); } void inject(AndroidSampleApp app); }
55. DaggerAppComponent .builder() .application(this) .build() .inject(this);
56. Activity builder
57. @Module public abstract class ActivityBuilder { }
58. @Module public abstract class ActivityBuilder { abstract AndroidInjector.Factory<? extends Activity> bindMainActivity(MainActivityComponent.Builder builder); }
59. @Module public abstract class ActivityBuilder { @Binds @IntoMap @ActivityKey(MainActivity.class) abstract AndroidInjector.Factory<? extends Activity> bindMainActivity(MainActivityComponent.Builder builder); }
60. @Module public abstract class ActivityBuilder { @Binds @IntoMap @ActivityKey(MainActivity.class) abstract AndroidInjector.Factory<? extends Activity> bindMainActivity(MainActivityComponent.Builder builder); @Binds @IntoMap @ActivityKey(DetailActivity.class) abstract AndroidInjector.Factory<? extends Activity> bindDetailActivity(DetailActivityComponent.Builder builder); }
61. App module
62. @Module(subcomponents = { MainActivityComponent.class, DetailActivityComponent.class}) public class AppModule { }
63. @Module(subcomponents = { MainActivityComponent.class, DetailActivityComponent.class}) public class AppModule { @Provides @Singleton Context provideContext(Application application) { return application; } }
64. Activity component
65. @Subcomponent(modules = MainActivityModule.class) public interface MainActivityComponent extends AndroidInjector<MainActivity> }
66. @Subcomponent(modules = MainActivityModule.class) public interface MainActivityComponent extends AndroidInjector<MainActivity> @Subcomponent.Builder abstract class Builder extends AndroidInjector.Builder<MainActivity>{} }
67. Activity module
68. @Module public class MainActivityModule { }
69. @Module public class MainActivityModule { @Provides MainView provideMainView(MainActivity mainActivity){ return mainActivity; } }
70. @Module public class MainActivityModule { @Provides MainView provideMainView(MainActivity mainActivity){ return mainActivity; } @Provides MainPresenter provideMainPresenter(MainView mainView, ApiService apiService){ return new MainPresenterImpl(mainView, apiService); } }
71. Application class
72. public class AndroidSampleApp extends Application implements HasActivityInjector { }
73. public class AndroidSampleApp extends Application implements HasActivityInjector { @Inject DispatchingAndroidInjector<Activity> activityDispatchingAndroidInjector; }
74. public class AndroidSampleApp extends Application implements HasActivityInjector { @Inject DispatchingAndroidInjector<Activity> activityDispatchingAndroidInjector; @Override public DispatchingAndroidInjector<Activity> activityInjector() { return activityDispatchingAndroidInjector; } }
75. Activity module
76. public class MainActivity extends Activity { }
77. public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { AndroidInjection.inject(this); super.onCreate(savedInstanceState); } }
78. 02 PRODUCERS
80. “The whole initialization process can be executed on background thread(s) and delivered later to app’s main thread”
81. @Module @Provide @Component
82. @ProducerModule @Produces @ProductionComponent
83. @ProducerModule
 public class ApiProducerModule { 
 @Produces
 public UserManager produceUserManager(ApiService apiService) {
 return new UserManager(apiService);
 }
 }
84. 
 @ProductionComponent(
 dependencies = AppComponent.class,
 modules = ApiProducerModule.class
 )
 public interface AppProductionComponent { 
 }
85. 
 @ProductionComponent(
 dependencies = AppComponent.class,
 modules = ApiProducerModule.class
 )
 public interface AppProductionComponent { 
 ListenableFuture<UserManager> userManager();
 
 ListenableFuture<UserModule.Factory> userModuleFactory();
 }
86. AppProductionComponent appProductionComponent = DaggerAppProductionComponent.builder()
87. AppProductionComponent appProductionComponent = DaggerAppProductionComponent.builder() .executor(Executors.newSingleThreadExecutor())
88. AppProductionComponent appProductionComponent = DaggerAppProductionComponent.builder() .executor(Executors.newSingleThreadExecutor()) .appComponent(appComponent)
89. AppProductionComponent appProductionComponent = DaggerAppProductionComponent.builder() .executor(Executors.newSingleThreadExecutor()) .appComponent(appComponent) .build();
90. appProductionComponent = splashActivity.getAppProductionComponent();
91. appProductionComponent = splashActivity.getAppProductionComponent();
 Futures.addCallback(appProductionComponent.userManager(), new FutureCallback<UserManager>() {
 @Override
 public void onSuccess(UserManager result) {
 SplashActivityPresenter.this.userManager = result;
 }
 
 @Override
 public void onFailure(Throwable t) {
 
 }
 });
92. • PRO • Background, baby! PRODUCERS
93. • PRO • Background, baby! • CONS • Guava → 15k methods • More complicated code PRODUCERS
94. Better Producer implementation
95. @Module
 public class AppModule {
 
 @Provides
 @Singleton
 Retrofit retrofit() {
 Retrofit retrofit = new Retrofit();
 retrofit.init();
 return retrofit;
 }
 
 }
96. @Module
 public class AppModule {
 
 @Provides
 @Singleton
 Retrofit provideHeavyExternalLibrary() {
 Retrofit retrofit = new Retrofit();
 retrofit.init();
 return retrofit;
 }
 
 @Provides
 @Singleton
 Observable<Retrofit> provideRetrofitObservable(
 final Lazy<Retrofit> retrofit) {
 return Observable.fromCallable(retrofit::get)
 .subscribeOn(Schedulers.io())
 .observeOn(AndroidSchedulers.mainThread());
 }
 }
97. public class MainActivity extends AppCompatActivity {
 
 }
98. public class MainActivity extends AppCompatActivity {
 
 @Inject
 Observable<Retrofit> retrofitObservable;
 
 Retrofit retrofit;
 
 }
99. public class MainActivity extends AppCompatActivity {
 
 @Inject
 Observable< Retrofit > retrofitObservable;
 
 Retrofit retrofit;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(); 
 }
 }
100. public class MainActivity extends AppCompatActivity {
 
 @Inject
 Observable< Retrofit > retrofitObservable;
 
 Retrofit retrofit;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(); 
 retrofitObservable.subscribe(
 );
 }
 }
101. public class MainActivity extends AppCompatActivity {
 
 @Inject
 Observable<Retrofit> retrofitObservable;
 
 Retrofit retrofit;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(); 
 retrofitObservable.subscribe(
 retrofit -> retrofit = retrofit,
 throwable -> {}
 );
 }
 }
102. 03 @SUBCOMPONENT.BUILDER
103. The old way
104. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 
 }
105. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent plus(FirstModule firstModule, SecondModule secondModule);
 }
106. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent plus(FirstModule firstModule, SecondModule secondModule);
 }
 
 @FirstScope
 @Subcomponent(modules = {FirstModule.class, SecondModule.class})
 public interface FirstComponent {
 
 }
107. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent plus(FirstModule firstModule, SecondModule secondModule);
 }
 
 @FirstScope
 @Subcomponent(modules = {FirstModule.class, SecondModule.class})
 public interface FirstComponent {
 void inject(MainActivity mainActivity);
 }
108. FirstComponent firstComponent = appComponent
109. FirstComponent firstComponent = appComponent.plus();
110. FirstComponent firstComponent = appComponent.plus( new FirstModule() );
111. FirstComponent firstComponent = appComponent.plus( new FirstModule(), new SecondModule() );
112. FirstComponent firstComponent = appComponent.plus( new FirstModule(), new SecondModule(), … , …, …, … );
113. With builder:
114. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent.Builder firstComponentBuilder();
 }
115. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent.Builder firstComponentBuilder();
 }
 
 @FirstScope
 @Subcomponent(modules = {FirstModule.class, SecondModule.class})
 public interface FirstComponent {
 
 }
116. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent.Builder firstComponentBuilder();
 }
 
 @FirstScope
 @Subcomponent(modules = {FirstModule.class, SecondModule.class})
 public interface FirstComponent {
 
 @Subcomponent.Builder
 interface Builder {
 }
 
 void inject(MainActivity mainActivity);
 
 }
117. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent.Builder firstComponentBuilder();
 }
 
 @FirstScope
 @Subcomponent(modules = {FirstModule.class, SecondModule.class})
 public interface FirstComponent {
 
 @Subcomponent.Builder
 interface Builder {
 FirstComponent.Builder firstModule(FirstModule firstModule);
 }
 
 void inject(MainActivity mainActivity);
 
 }
118. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent.Builder firstComponentBuilder();
 }
 
 @FirstScope
 @Subcomponent(modules = {FirstModule.class, SecondModule.class})
 public interface FirstComponent {
 
 @Subcomponent.Builder
 interface Builder {
 FirstComponent.Builder firstModule(FirstModule firstModule);
 FirstComponent.Builder secondModule(SecondModule secondModule);
 
 }
 
 void inject(MainActivity mainActivity);
 
 }
119. @Component(modules = {AppModule.class, UtilsModule.class})
 @Singleton
 public interface AppComponent {
 FirstComponent.Builder firstComponentBuilder();
 }
 
 @FirstScope
 @Subcomponent(modules = {FirstModule.class, SecondModule.class})
 public interface FirstComponent {
 
 @Subcomponent.Builder
 interface Builder {
 FirstComponent.Builder firstModule(FirstModule firstModule);
 FirstComponent.Builder secondModule(SecondModule secondModule);
 FirstComponent build();
 }
 
 void inject(MainActivity mainActivity);
 
 }
120. FirstComponent firstComponent = appComponent
 .firstComponentBuilder()
121. FirstComponent firstComponent = appComponent
 .firstComponentBuilder()
 .firstModule(new FirstModule())
122. FirstComponent firstComponent = appComponent
 .firstComponentBuilder()
 .firstModule(new FirstModule())
 .secondModule(new SecondModule())
123. FirstComponent firstComponent = appComponent
 .firstComponentBuilder()
 .firstModule(new FirstModule())
 .secondModule(new SecondModule())
 .build();
124. 04 STATIC
125. @Provides User currentUser(AuthManager authManager) {
 return authManager.currentUser();
 }
126. @Provides User currentUser(AuthManager authManager) {
 return authManager.currentUser();
 }
 
 @Provides @Singleton User currentUser(AuthManager authManager) {
 return authManager.currentUser();
 }

127. @Provides static User currentUser(AuthManager authManager) {
 return authManager.currentUser();
 }
128. “calling a static method is 15–20% faster than non- static counterpart”
129. 05 MULTIBINDINGS
130. @Module
 public class TranslatorsModule {
 
 @Provides
 @Singleton
 public Translator provideGoogleTranslator(){
 return new GoogleTranslator();
 }
 }
131. @Module
 public class TranslatorsModule {
 
 @Provides(type = Provides.Type.SET)
 @Singleton
 public Translator provideGoogleTranslator(){
 return new GoogleTranslator();
 }
 }
132. @Module
 public class TranslatorsModule {
 
 @Provides(type = Provides.Type.SET)
 @Singleton
 public Translator provideGoogleTranslator() {
 return new GoogleTranslator();
 } 
 
 ...
 
 @Provides(type = Provides.Type.SET)
 @Singleton
 public Translator provideLongmanTranslator() {
 return new LongmanTranslator();
 }
 }
133. public class TranslatorActivity extends Activity {
 
 @Inject
 Set<Translator> translators; 
 }
134. MORE NEW FUNCTIONALITIES! • Releasable reference • @Binds • @BindsOptionalOf • @BindsInstance
135. REFERENCES • https://android.jlelse.eu/dagger-2-part-i-basic-principles-graph- dependencies-scopes-3dfd032ccd82 • https://medium.com/@iammert/new-android-injector-with-dagger-2- part-1-8baa60152abe • https://proandroiddev.com/dagger-2-part-three-new- possibilities-3daff12f7ebf • https://google.github.io/dagger/users-guide.html • https://stackoverflow.com/a/39154297
136. Visit infinum.co or find us on social networks: infinum.co infinumco infinumco infinum Any questions? DINO.BIKIC@INFINUM.CO @DINO_BIKIC