Helping Dagger Help You (Droidcon UK 2018)

As applications grow in size, Dagger can help mitigate the pain of dependency management and eliminate the boilerplate of manual dependency injection. Despite this, there are still pain points such as slower compilation times and how to inject objects like activities and views. This talk will cover functionality provided by libraries which build on top of Dagger to reduce these pain points. We'll learn what assisted injection is, why you might use it, and look at a library which simplifies the pattern. And finally we'll attempt to solve the build speed problem so that development builds are as fast as possible without sacrificing Dagger's compile-time safety.

Video: http://uk.droidcon.com/skillscasts/11617-helping-dagger-help-you

Transcript

1. Helping
   Dagger
   Help
   You
   @JakeWharton
   

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2. boilerplate
   /ˈbɔɪləpleɪt/
   noun
   standardized pieces of text for use as clauses in
   contracts or as part of a computer program
   

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3. verbosity
   /vəˈbɒsɪti/
   noun
   the fact or quality of using more words
   than needed; wordiness
   

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4. View Slide

5. View Slide

6. Dagger
   

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7. Dagger
   

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8. Service Locator
   

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9. Manual Dependency Injection
   

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10. Manual Dependency Injection
    

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11. Manual Dependency Injection
    

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12. Service Locator
    

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13. Dagger
    

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14. Dagger
    

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15. Dagger
    

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16. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    // …
    }Y
    

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17. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    // which profile do we load?
    }Y
    

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18. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    // which profile do we load?
    // what initials do we render the avatar placeholder with?
    }Y
    

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19. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    // which profile do we load?
    // what initials do we render the avatar placeholder with?
    // which image url do we download?
    }Y
    

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20. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    lateinit var userId: String
    // which profile do we load?
    // what initials do we render the avatar placeholder with?
    // which image url do we download?
    }Y
    

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21. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    lateinit var userId: String
    // which profile do we load?
    // what initials do we render the avatar placeholder with?
    // which image url do we download?
    }Y
    var userId: String = …
    

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22. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    lateinit var userId: String
    // which profile do we load?
    // what initials do we render the avatar placeholder with?
    // which image url do we download?
    }Y
    var userId: String = …
    presenter.userId = userId
    

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23. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    lateinit var userId: String
    // which profile do we load?
    // what initials do we render the avatar placeholder with?
    // which image url do we download?
    }Y
    var userId: String = …
    presenter.userId = userId
    // Use presenter…
    

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24. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    lateinit var userId: String
    // …
    }Y
    var userId: String = …
    presenter.userId = userId
    // Use presenter…
    

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25. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    var userId: String = …
    presenter.userId = userId
    // Use presenter…
    

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26. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    // Use presenter…
    

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27. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    // Use presenter…
    

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28. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    @UserId var userId: String
    ) {
    // …
    }Y
    // Use presenter…
    

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29. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    // Use presenter…
    

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30. class ProfilePresenter @Inject constructor(A
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    

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31. class ProfilePresenter(A
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    

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32. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory
    }Y
    

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33. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    )G
    }Y
    

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34. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    )G{
    fun create(userId: String)
    }Z
    }Y
    

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35. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    )G{
    fun create(userId: String) =
    ProfilePresenter(imageLoader, profilePersistence,
    avatarRenderer, userId)
    }Z
    }Y
    

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36. class ProfilePresenter(…) {
    // …
    class Factory @Inject constructor(…)G{
    fun create(userId: String) =
    ProfilePresenter(imageLoader, profilePersistence,
    avatarRenderer, userId)
    }Z
    }Y
    

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37. class ProfilePresenter(…) {
    // …
    class Factory @Inject constructor(…) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader, profilePersistence,
    avatarRenderer, userId)
    }Z
    }Y
    var userId: String = …
    

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38. class ProfilePresenter(…) {
    // …
    class Factory @Inject constructor(…) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader, profilePersistence,
    avatarRenderer, userId)
    }Z
    }Y
    var userId: String = …
    val presenter = presenterFactory.create(userId)
    // Use presenter…
    

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39. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader, profilePersistence,
    avatarRenderer, userId)
    }Z
    }Y
    

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40. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence:val avatarRenderer: AvatarRenderer
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader, profilePersistence,
    avatarRenderer, userId)
    }Z
    }Y
    

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41. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    

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42. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    

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43. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    

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44. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    

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45. class ProfilePresenter {
    private final ImageLoader imageLoader;
    private final ProfilePersistence profilePersistence;
    private final AvatarRenderer avatarRenderer;
    private final String userId;
    ProfilePresenter(
    ImageLoader imageLoader, ProfilePersistence profilePersistence,
    AvatarRenderer avatarRenderer, String userId) {
    this.imageLoader = imageLoader;
    this.profilePersistence = profilePersistence;
    this.avatarRenderer = avatarRenderer;
    this.userId = userId;
    }A
    // …
    static final class Factory {
    private final Provider imageLoader;
    

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46. // …
    static final class Factory {
    private final Provider imageLoader;
    private final Provider profilePersistence;
    private final Provider avatarRenderer;
    @Inject Factory(Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) {
    this.imageLoader = imageLoader;
    this.profilePersistence = profilePersistence;
    this.avatarRenderer = avatarRenderer;
    }B
    public ProfilePresenter create(String userId) {
    return new ProfilePresenter(imageLoader.get(),
    profilePersistence.get(), avatarRenderer.get(), userId);
    }C
    }D
    }E
    

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47. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    )G{
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    i
    n
    t
    e
    r
    f
    a
    c
    e
    

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48. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    interface FactoryG{
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    

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49. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    interface Factory {
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    install(FactoryModuleBuilder()
    .build(ProfilePresenter::class.java))
    

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50. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    interface Factory {
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    install(FactoryModuleBuilder()
    .build(ProfilePresenter::class.java))
    

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51. class ProfilePresenter @Inject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    @Assisted var userId: String
    ) {
    // …
    interface Factory {
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    install(FactoryModuleBuilder()
    .build(ProfilePresenter::class.java))
    

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52. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    

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53. @AutoFactory class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    ) {
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    

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54. @AutoFactory class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    

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55. @AutoFactory class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    @Generated
    final class ProfilePresenterFactory {
    @Inject
    ProfilePresenterFactory(Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) { … }
    ProfilePresenter create(userId: String) { … }
    }Z
    

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56. @AutoFactory class ProfilePresenter(
    @Provided val imageLoader: ImageLoader,
    @Provided val profilePersistence: ProfilePersistence,
    @Provided val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    @Generated
    final class ProfilePresenterFactory {
    @Inject
    ProfilePresenterFactory(Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) { … }
    ProfilePresenter create(userId: String) { … }
    }Z
    

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57. @AutoFactory class ProfilePresenter(
    @Provided val imageLoader: ImageLoader,
    @Provided val profilePersistence: ProfilePersistence,
    @Provided val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    @Generated
    final class ProfilePresenterFactory {
    @Inject
    ProfilePresenterFactory(Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) { … }
    ProfilePresenter create(userId: String) { … }
    }Z
    

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58. @AutoFactory class ProfilePresenter(
    @Provided val imageLoader: ImageLoader,
    @Provided val profilePersistence: ProfilePersistence,
    @Provided val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    @Generated
    final class ProfilePresenterFactory {
    @Inject
    ProfilePresenterFactory(Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) { … }
    ProfilePresenter create(userId: String) { … }
    }Z
    

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59. @AutoFactory class ProfilePresenter(
    @Provided val imageLoader: ImageLoader,
    @Provided val profilePersistence: ProfilePersistence,
    @Provided val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    }Y
    @Generated
    final class ProfilePresenterFactory {
    @Inject
    ProfilePresenterFactory(Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) { … }
    ProfilePresenter create(userId: String) { … }
    }Z
    

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60. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    class Factory @Inject constructor(
    val imageLoader: Provider,
    val profilePersistence: Provider,
    val avatarRenderer: Provider
    )G{
    fun create(userId: String) =
    ProfilePresenter(imageLoader.get(), profilePersistence.get(),
    avatarRenderer.get(), userId)
    }Z
    }Y
    i
    n
    t
    e
    r
    f
    a
    c
    e
    

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61. class ProfilePresenter(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    interface FactoryG{
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    

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62. class ProfilePresenter @AssistedInject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    var userId: String
    ) {
    // …
    interface FactoryG{
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    

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63. class ProfilePresenter @AssistedInject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    @Assisted var userId: String
    ) {
    // …
    interface FactoryG{
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    

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64. class ProfilePresenter @AssistedInject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    @Assisted var userId: String
    ) {
    // …
    @AssistedInject.Factory
    interface FactoryG{
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    

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65. @Generated
    class AssistedInject_ProfilePresenter implements ProfilePresenter.Factory {
    private final Provider imageLoader;
    private final Provider profilePersistence;
    private final Provider avatarRenderer;
    @Inject AssistedInject_ProfilePresenter(
    Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) {
    this.imageLoader = imageLoader;
    this.profilePersistence = profilePersistence;
    this.avatarRenderer = avatarRenderer;
    }
    @Override public ProfilePresenter create(String userId) {
    return new ProfilePresenter(imageLoader.get(),
    profilePersistence.get(), avatarRenderer.get(), userId);
    }
    }
    

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66. @Generated
    class AssistedInject_ProfilePresenter implements ProfilePresenter.Factory {
    private final Provider imageLoader;
    private final Provider profilePersistence;
    private final Provider avatarRenderer;
    @Inject AssistedInject_ProfilePresenter(
    Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) {
    this.imageLoader = imageLoader;
    this.profilePersistence = profilePersistence;
    this.avatarRenderer = avatarRenderer;
    }
    @Override public ProfilePresenter create(String userId) {
    return new ProfilePresenter(imageLoader.get(),
    profilePersistence.get(), avatarRenderer.get(), userId);
    }
    }
    

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67. @Generated
    class AssistedInject_ProfilePresenter implements ProfilePresenter.Factory {
    private final Provider imageLoader;
    private final Provider profilePersistence;
    private final Provider avatarRenderer;
    @Inject AssistedInject_ProfilePresenter(
    Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) {
    this.imageLoader = imageLoader;
    this.profilePersistence = profilePersistence;
    this.avatarRenderer = avatarRenderer;
    }
    @Override public ProfilePresenter create(String userId) {
    return new ProfilePresenter(imageLoader.get(),
    profilePersistence.get(), avatarRenderer.get(), userId);
    }
    }
    

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68. @Generated
    class AssistedInject_ProfilePresenter implements ProfilePresenter.Factory {
    private final Provider imageLoader;
    private final Provider profilePersistence;
    private final Provider avatarRenderer;
    @Inject AssistedInject_ProfilePresenter(
    Provider imageLoader,
    Provider profilePersistence,
    Provider avatarRenderer) {
    this.imageLoader = imageLoader;
    this.profilePersistence = profilePersistence;
    this.avatarRenderer = avatarRenderer;
    }
    @Override public ProfilePresenter create(String userId) {
    return new ProfilePresenter(imageLoader.get(),
    profilePersistence.get(), avatarRenderer.get(), userId);
    }
    }
    

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69. class ProfilePresenter @AssistedInject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    @Assisted var userId: String
    ) {
    // …
    @AssistedInject.Factory
    interface Factory {
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    

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70. class ProfilePresenter @AssistedInject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    @Assisted var userId: String
    ) {
    // …
    @AssistedInject.Factory
    interface Factory {
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    

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71. class ProfilePresenter @AssistedInject constructor(
    val imageLoader: ImageLoader,
    val profilePersistence: ProfilePersistence,
    val avatarRenderer: AvatarRenderer,
    @Assisted var userId: String
    ) {
    // …
    @AssistedInject.Factory
    interface Factory {
    fun create(userId: String): ProfilePresenter
    }Z
    }Y
    class AssistedInject_ProfilePresenter implements ProfilePresenter.Factory {
    @Inject AssistedInject_ProfilePresenter(…)
    }
    

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72. @Module
    abstract class AssistedModule {
    }S
    

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73. @Module
    abstract class AssistedModule {
    @Binds
    abstract fun bindProfilePresenterFactory(
    factory: AssistedInject_ProfilePresenter): ProfilePresenter.Factory
    }S
    

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74. @Module
    abstract class AssistedModule {
    @Binds
    abstract fun bindProfilePresenterFactory(
    factory: AssistedInject_ProfilePresenter): ProfilePresenter.Factory
    }S
    

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75. @Module
    abstract class AssistedModule {
    @Binds
    abstract fun bindProfilePresenterFactory(
    factory: AssistedInject_ProfilePresenter): ProfilePresenter.Factory
    }S
    

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76. @Module
    abstract class AssistedModule {
    @Binds
    abstract fun bindProfilePresenterFactory(
    factory: AssistedInject_ProfilePresenter): ProfilePresenter.Factory
    }S
    

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77. @Module
    abstract class AssistedModule {
    @Binds
    abstract fun bindProfilePresenterFactory(
    factory: AssistedInject_ProfilePresenter): ProfilePresenter.Factory
    }S
    @Component(modules = [PresenterModule::class])
    interface PresenterComponent {
    // …
    }T
    

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78. @Module
    abstract class AssistedModule {
    @Binds
    abstract fun bindProfilePresenterFactory(
    factory: AssistedInject_ProfilePresenter): ProfilePresenter.Factory
    }S
    @Component(modules = [PresenterModule::class, AssistedModule::class])
    interface PresenterComponent {
    // …
    }T
    

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79. @Module
    object PresenterModule {
    @JvmStatic @Provides
    fun thing() = Thing("API key")
    }H
    

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80. @AssistedModule
    @Module
    object PresenterModule {
    @JvmStatic @Provides
    fun thing() = Thing("API key")
    }H
    

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81. @AssistedModule
    @Module
    object PresenterModule {
    @JvmStatic @Provides
    fun thing() = Thing("API key")
    }H
    @Module
    @Generated
    abstract class AssistedModule_PresenterModule {
    @Binds
    abstract ProfilePresenter.Factory bindProfilePresenterFactory(
    AssistedInject_ProfilePresenter factory)
    }S
    

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82. @AssistedModule
    @Module(includes = [AssistedModule_PresenterModule::class])
    object PresenterModule {
    @JvmStatic @Provides
    fun thing() = Thing("API key")
    }H
    @Module
    @Generated
    abstract class AssistedModule_PresenterModule {
    @Binds
    abstract ProfilePresenter.Factory bindProfilePresenterFactory(
    AssistedInject_ProfilePresenter factory)
    }S
    

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83. @AssistedModule
    @Module(includes = [AssistedModule_PresenterModule::class])
    object PresenterModule {
    @JvmStatic @Provides
    fun thing() = Thing("API key")
    }H
    @Module
    @Generated
    abstract class AssistedModule_PresenterModule {
    @Binds
    abstract ProfilePresenter.Factory bindProfilePresenterFactory(
    AssistedInject_ProfilePresenter factory)
    // …
    }S
    

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84. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    

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85. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    

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86. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    

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87. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    @Module
    abstract class MainActivityModule {
    }A
    

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88. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    @Module
    abstract class MainActivityModule {
    @ContributesAndroidInjector
    abstract fun contributeMainActivity(): MainActivity
    }A
    

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89. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    @Module
    abstract class MainActivityModule {
    @ContributesAndroidInjector
    abstract fun contributeMainActivity(): MainActivity
    }A
    @Component(modules = [MainActivityModule::class])
    interface AppComponent
    

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90. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    @Module
    abstract class MainActivityModule {
    @ContributesAndroidInjector
    abstract fun contributeMainActivity(): MainActivity
    }A
    @Component(modules = [MainActivityModule::class])
    interface AppComponent
    @Module
    abstract class MainActivityModule_ContributeMainActivity { … }
    

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91. class MainActivity : Activity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    AndroidInjection.inject(this)
    }C
    }B
    @Module
    abstract class MainActivityModule {
    @ContributesAndroidInjector
    abstract fun contributeMainActivity(): MainActivity
    }A
    @Component(modules = [MainActivityModule::class])
    interface AppComponent
    @Module
    abstract class MainActivityModule_ContributeMainActivity { … }
    

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92. View Slide

93. View Slide

94. dependencies {
    compileOnly 'com.squareup.inject:assisted-inject-annotations-dagger2:0.3.0'
    kapt 'com.squareup.inject:assisted-inject-processor-dagger2:0.3.0'
    }A
    

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95. dependencies {
    compileOnly 'com.squareup.inject:assisted-inject-annotations-dagger2:0.3.0'
    kapt 'com.squareup.inject:assisted-inject-processor-dagger2:0.3.0'
    // or 'annotationProcessor'…
    }A
    

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96. class ProfileView(context: Context, attrs: AttributeSet)
    : ConstraintLayout(context, attrs) {
    }Z
    

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97. class ProfileView(context: Context, attrs: AttributeSet)
    : ConstraintLayout(context, attrs) {
    lateinit var imageLoader: ImageLoader
    lateinit var avatarRenderer: AvatarRenderer
    }Z
    

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98. class ProfileView(context: Context, attrs: AttributeSet)
    : ConstraintLayout(context, attrs) {
    lateinit var imageLoader: ImageLoader
    lateinit var avatarRenderer: AvatarRenderer
    fun showProfile(profile: Profile) {
    // Use avatarRenderer…
    // Use imageLoader…
    }Y
    }Z
    

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99. class ProfileView(context: Context, attrs: AttributeSet)
    : ConstraintLayout(context, attrs) {
    lateinit var imageLoader: ImageLoader
    lateinit var avatarRenderer: AvatarRenderer
    fun showProfile(profile: Profile) {
    // Use avatarRenderer…
    // Use imageLoader…
    }Y
    }Z
    class ProfilePresenter @AssistedInject constructor(
    val imageLoader: ImageLoader, val avatarRenderer: AvatarRenderer, /*…*/
    ) {
    }I
    

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100. class ProfileView(context: Context, attrs: AttributeSet)
     : ConstraintLayout(context, attrs) {
     lateinit var imageLoader: ImageLoader
     lateinit var avatarRenderer: AvatarRenderer
     fun showProfile(profile: Profile) {
     // Use avatarRenderer…
     // Use imageLoader…
     }Y
     }Z
     class ProfilePresenter @AssistedInject constructor(
     val imageLoader: ImageLoader, val avatarRenderer: AvatarRenderer, /*…*/
     ) {
     fun attachView(view: ProfileView) {
     }W
     }I
     

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101. l
     l
     class ProfileView(context: Context, attrs: AttributeSet)G
     : ConstraintLayout(context, attrs) {
     lateinit var imageLoader: ImageLoader
     lateinit var avatarRenderer: AvatarRenderer
     fun showProfile(profile: Profile) {
     // Use avatarRenderer…
     // Use imageLoader…
     }Y
     }Z
     class ProfilePresenter @AssistedInject constructor(
     val imageLoader: ImageLoader, val avatarRenderer: AvatarRenderer, /*…*/
     ) {
     fun attachView(view: ProfileView) {
     view.imageLoader = imageLoader
     view.avatarRenderer = avatarRenderer
     }W
     }I
     

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102. r
     r
     class ProfileView(
     context: Context, attrs: AttributeSet,
     val imageLoader: ImageLoader,
     val avatarRenderer: AvatarRenderer
     )G: ConstraintLayout(context, attrs) {
     fun showProfile(profile: Profile) {
     // Use avatarRenderer…
     // Use imageLoader…
     }Y
     }Z
     class ProfilePresenter @AssistedInject constructor(
     val imageLoader: ImageLoader, val avatarRenderer: AvatarRenderer, /*…*/
     ) {
     fun attachView(view: ProfileView) {
     view.imageLoader = imageLoader
     view.avatarRenderer = avatarRenderer
     }W
     }I
     

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103. class ProfileView(
     context: Context, attrs: AttributeSet,
     val imageLoader: ImageLoader,
     val avatarRenderer: AvatarRenderer
     )G: ConstraintLayout(context, attrs) {
     fun showProfile(profile: Profile) {
     // Use avatarRenderer…
     // Use imageLoader…
     }Y
     }Z
     class ProfilePresenter @AssistedInject constructor(
     val imageLoader: ImageLoader, val avatarRenderer: AvatarRenderer, /*…*/
     ) {
     fun attachView(view: ProfileView) {
     }W
     }I
     

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104. class ProfileView(
     context: Context, attrs: AttributeSet,
     val imageLoader: ImageLoader,
     val avatarRenderer: AvatarRenderer
     )G: ConstraintLayout(context, attrs) {
     fun showProfile(profile: Profile) {
     // Use avatarRenderer…
     // Use imageLoader…
     }Y
     }Z
     class ProfilePresenter @AssistedInject constructor(/*…*/) {
     fun attachView(view: ProfileView) {
     }W
     }I
     

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105. class ProfileView(
     context: Context, attrs: AttributeSet,
     val imageLoader: ImageLoader,
     val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     fun showProfile(profile: Profile) {
     // Use avatarRenderer…
     // Use imageLoader…
     }Y
     }Z
     class ProfilePresenter @AssistedInject constructor(/*…*/) {
     fun attachView(view: ProfileView) {
     }W
     }I
     

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106. class LayoutInflater {
     }A
     

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107. class LayoutInflater {
     interface Factory {
     }B
     }A
     

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108. class LayoutInflater {
     interface Factory {
     @Nullable
     View onCreateView(
     @NonNull String name,
     @NonNull Context context,
     @NonNull AttributeSet attrs);
     }B
     }A
     

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109. class LayoutInflater {
     interface Factory {
     @Nullable
     View onCreateView(
     @NonNull String name,
     @NonNull Context context,
     @NonNull AttributeSet attrs);
     }B
     }A
     class MyAppFactory : LayoutInflater.Factory {
     }P
     

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110. class LayoutInflater {
     interface Factory {
     @Nullable
     View onCreateView(
     @NonNull String name,
     @NonNull Context context,
     @NonNull AttributeSet attrs);
     }B
     }A
     class MyAppFactory : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     }O
     }P
     

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111. class LayoutInflater {
     interface Factory {
     @Nullable
     View onCreateView(
     @NonNull String name,
     @NonNull Context context,
     @NonNull AttributeSet attrs);
     }B
     }A
     class MyAppFactory : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return TODO()
     }I
     }O
     }P
     

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112. class LayoutInflater {
     interface Factory {
     @Nullable
     View onCreateView(
     @NonNull String name,
     @NonNull Context context,
     @NonNull AttributeSet attrs);
     }B
     }A
     class MyAppFactory : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return TODO()
     }I
     return null
     }O
     }P
     

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113. class ProfileView(
     context: Context, attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     }Z
     

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114. class ProfileView(G
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     }Z
     

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115. class ProfileView @AssistedInject constructor(G
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     }Z
     

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116. class ProfileView @AssistedInject constructor(G
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory {
     fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     

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117. class MyAppFactory : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return TODO()
     }I
     return null
     }O
     }P
     

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118. class MyAppFactory @Inject constructor() : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return TODO()
     }I
     return null
     }O
     }P
     

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119. class MyAppFactory @Inject constructor(
     private val profileViewFactory: ProfileView.Factory
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return TODO()
     }I
     return null
     }O
     }P
     

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120. class MyAppFactory @Inject constructor(
     private val profileViewFactory: ProfileView.Factory
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return profileViewFactory.create(context, attrs)
     }I
     return null
     }O
     }P
     

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121. class MyAppFactory @Inject constructor(
     private val profileViewFactory: ProfileView.Factory,
     private val cartViewFactory: CartView.Factory
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return profileViewFactory.create(context, attrs)
     }I
     if (name == CartView::class.java.name) {
     return cartViewFactory.create(context, attrs)
     }I
     return null
     }O
     }P
     

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122. class MyAppFactory @Inject constructor(
     private val profileViewFactory: ProfileView.Factory,
     private val cartViewFactory: CartView.Factory,
     private val checkoutViewFactory: CheckoutView.Factory
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return profileViewFactory.create(context, attrs)
     }I
     if (name == CartView::class.java.name) {
     return cartViewFactory.create(context, attrs)
     }I
     if (name == CheckoutView::class.java.name) {
     return checkoutViewFactory.create(context, attrs)
     }I
     return null
     }O
     }P
     

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123. class MyAppFactory @Inject constructor(
     private val viewFactories: Map
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     if (name == ProfileView::class.java.name) {
     return profileViewFactory.create(context, attrs)
     }I
     if (name == CartView::class.java.name) {
     return cartViewFactory.create(context, attrs)
     }I
     if (name == CheckoutView::class.java.name) {
     return checkoutViewFactory.create(context, attrs)
     }I
     return null
     }O
     }P
     private val profileViewFactory: ProfileView.Factory,
     private val cartViewFactory: CartView.Factory,
     private val checkoutViewFactory: CheckoutView.Factory
     

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124. class MyAppFactory @Inject constructor(
     private val viewFactories: Map
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     return viewFactories[name]?.create(context, attrs)
     }O
     }P
     if (name == ProfileView::class.java.name) {
     return profileViewFactory.create(context, attrs)
     }I
     if (name == CartView::class.java.name) {
     return cartViewFactory.create(context, attrs)
     }I
     if (name == CheckoutView::class.java.name) {
     return checkoutViewFactory.create(context, attrs)
     }I null
     

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125. class MyAppFactory @Inject constructor(
     private val viewFactories: Map
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     return viewFactories[name]?.create(context, attrs)
     }O
     }P
     interface ViewFactory {
     fun create(context: Context, attrs: AttributeSet): View
     }
     

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126. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory {A
     fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     

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127. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory : ViewFactory {A
     override fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     

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128. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory : ViewFactory {
     override fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     @Module
     abstract class ViewModule {
     }Q
     

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129. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory : ViewFactory {
     override fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     @Module
     abstract class ViewModule {
     @Binds
     abstract fun profileView(factory: ProfileView.Factory): ViewFactory
     }Q
     

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130. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory : ViewFactory {
     override fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     @Module
     abstract class ViewModule {
     @Binds
     @IntoMap
     abstract fun profileView(factory: ProfileView.Factory): ViewFactory
     }Q
     

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131. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory : ViewFactory {
     override fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     @Module
     abstract class ViewModule {
     @Binds
     @IntoMap
     @StringKey("com.example.ProfileView")
     abstract fun profileView(factory: ProfileView.Factory): ViewFactory
     }Q
     

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132. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory : ViewFactory {
     override fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     @Module
     abstract class ViewModule {
     @Binds
     @IntoMap
     @StringKey("com.example.ProfileView")
     abstract fun profileView(factory: ProfileView.Factory): ViewFactory
     }Q
     

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133. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     @AssistedInject.Factory
     interface Factory : ViewFactory {
     override fun create(context: Context, attrs: AttributeSet): ProfileView
     }G
     }Z
     @Module
     abstract class ViewModule {
     @Binds
     @IntoMap
     @StringKey("com.example.ProfileView")
     abstract fun profileView(factory: ProfileView.Factory): ViewFactory
     }Q
     

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134. class ProfileView @AssistedInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     // …
     }Z
     

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135. class ProfileView @InflationInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     // …
     }Z
     @Assisted
     

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136. class ProfileView @InflationInject constructor(
     @Assisted context: Context, @Assisted attrs: AttributeSet,
     private val imageLoader: ImageLoader,
     private val avatarRenderer: AvatarRenderer
     ) : ConstraintLayout(context, attrs) {
     // …
     }Z
     

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137. @Generated
     class InflationInject_ProfileView implements ViewFactory {
     private final Provider imageLoader;
     private final Provider avatarRenderer;
     @Inject InflationInject_ProfileView(
     Provider imageLoader,
     Provider avatarRenderer) {
     this.imageLoader = imageLoader;
     this.avatarRenderer = avatarRenderer;
     }
     @Override public View create(Context context, AttributeSet attrs) {
     return new ProfileView(
     context, attrs, imageLoader.get(), avatarRenderer.get());
     }
     }
     

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138. @Generated
     class InflationInject_ProfileView implements ViewFactory {
     private final Provider imageLoader;
     private final Provider avatarRenderer;
     @Inject InflationInject_ProfileView(
     Provider imageLoader,
     Provider avatarRenderer) {
     this.imageLoader = imageLoader;
     this.avatarRenderer = avatarRenderer;
     }
     @Override public View create(Context context, AttributeSet attrs) {
     return new ProfileView(
     context, attrs, imageLoader.get(), avatarRenderer.get());
     }
     }
     

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139. @Generated
     class InflationInject_ProfileView implements ViewFactory {
     private final Provider imageLoader;
     private final Provider avatarRenderer;
     @Inject InflationInject_ProfileView(
     Provider imageLoader,
     Provider avatarRenderer) {
     this.imageLoader = imageLoader;
     this.avatarRenderer = avatarRenderer;
     }
     @Override public View create(Context context, AttributeSet attrs) {
     return new ProfileView(
     context, attrs, imageLoader.get(), avatarRenderer.get());
     }
     }
     

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140. @Module
     object ViewModule {
     }H
     

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141. @InflationModule
     @Module
     object ViewModule {
     }H
     

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142. @InflationModule
     @Module
     object ViewModule {
     }H
     @Module
     @Generated
     abstract class InflationModule_ViewModule {
     @Binds
     @IntoMap
     @StringKey("com.example.ProfileView")
     abstract ViewFactory bindProfileView(
     InflationInject_ProfileView factory)
     }S
     

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143. @InflationModule
     @Module(includes = [InflationModule_ViewModule::class])
     object ViewModule {
     }H
     @Module
     @Generated
     abstract class InflationModule_ViewModule {
     @Binds
     @IntoMap
     @StringKey("com.example.ProfileView")
     abstract ViewFactory bindProfileView(
     InflationInject_ProfileView factory)
     }S
     

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144. @InflationModule
     @Module(includes = [InflationModule_ViewModule::class])
     object ViewModule {
     }H
     @Module
     @Generated
     abstract class InflationModule_ViewModule {
     @Binds
     @IntoMap
     @StringKey("com.example.ProfileView")
     abstract ViewFactory bindProfileView(
     InflationInject_ProfileView factory)
     // …
     }S
     

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145. class MyAppFactory @Inject constructor(
     private val viewFactories: Map
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     return viewFactories[name]?.create(context, attrs)
     }O
     }P
     

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146. class InflationInjectFactory @Inject constructor(
     private val viewFactories: Map
     ) : LayoutInflater.Factory {
     override fun onCreateView(name: String,
     context: Context, attrs: AttributeSet): View? {
     return viewFactories[name]?.create(context, attrs)
     }O
     }P
     

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147. class ProfileActivity : Activity() {
     }A
     

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148. class ProfileActivity : Activity() {
     override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     AndroidInjection.inject(this)
     }B
     }A
     

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149. class ProfileActivity : Activity() {
     @Inject lateinit var presenterFactory: ProfilePresenter.Factory
     @Inject lateinit var inflationFactory: InflationInjectFactory
     override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     AndroidInjection.inject(this)
     }B
     }A
     

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150. class ProfileActivity : Activity() {
     @Inject lateinit var presenterFactory: ProfilePresenter.Factory
     @Inject lateinit var inflationFactory: InflationInjectFactory
     override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     AndroidInjection.inject(this)
     layoutInflater.factory = inflationFactory
     }B
     }A
     

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151. class ProfileActivity : Activity() {
     @Inject lateinit var presenterFactory: ProfilePresenter.Factory
     @Inject lateinit var inflationFactory: InflationInjectFactory
     override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     AndroidInjection.inject(this)
     layoutInflater.factory = inflationFactory
     setContentView(R.layout.profile_view)
     }B
     }A
     

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152. class ProfileActivity : Activity() {
     @Inject lateinit var presenterFactory: ProfilePresenter.Factory
     @Inject lateinit var inflationFactory: InflationInjectFactory
     override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     AndroidInjection.inject(this)
     layoutInflater.factory = inflationFactory
     setContentView(R.layout.profile_view)
     val userId = intent.getStringExtra("userId")
     val presenter = presenterFactory.create(userId)
     presenter.attachView(findViewById(R.id.profile_view)
     }B
     }A
     

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153. class ProfileActivity : Activity() {
     @Inject lateinit var presenterFactory: ProfilePresenter.Factory
     @Inject lateinit var inflationFactory: InflationInjectFactory
     override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     AndroidInjection.inject(this)
     layoutInflater.factory = inflationFactory
     setContentView(R.layout.profile_view)
     val userId = intent.getStringExtra("userId")
     val presenter = presenterFactory.create(userId)
     presenter.attachView(findViewById(R.id.profile_view)
     }B
     }A
     l
     l
     

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154. class ProfileActivity @Inject constructor(
     val presenterFactory: ProfilePresenter.Factory
     val inflationFactory: InflationInjectFactory
     : Activity() {
     override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     AndroidInjection.inject(this)
     layoutInflater.factory = inflationFactory
     setContentView(R.layout.profile_view)
     val userId = intent.getStringExtra("userId")
     val presenter = presenterFactory.create(userId)
     presenter.attachView(findViewById(R.id.profile_view)
     }B
     }A
     @
     I
     n
     j
     e
     c
     t l
     a
     t
     e
     i
     n
     i
     t r
     @
     I
     n
     j
     e
     c
     t l
     a
     t
     e
     i
     n
     i
     t r
     

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155. View Slide

156. View Slide

157. View Slide

158. dependencies {
     compileOnly 'com.squareup.inject:inflation-inject:0.3.0'
     kapt 'com.squareup.inject:inflation-inject-processor:0.3.0'
     }A
     

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159. dependencies {
     compileOnly 'com.squareup.inject:inflation-inject:0.3.0'
     kapt 'com.squareup.inject:inflation-inject-processor:0.3.0'
     // or 'annotationProcessor'…
     }A
     

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160. View Slide

161. View Slide

162. View Slide

163. View Slide

164. View Slide

165. View Slide

166. allprojects {
     }A
     

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167. allprojects {
     tasks.withType(JavaCompile).all {
     }B
     }A
     

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168. allprojects {
     tasks.withType(JavaCompile).all {
     options.compilerArgs += []C
     }B
     }A
     

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169. allprojects {
     tasks.withType(JavaCompile).all {
     options.compilerArgs += [
     '-Adagger.formatGeneratedSource=disabled'
     ]C
     }B
     }A
     

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170. allprojects {
     tasks.withType(JavaCompile).all {
     options.compilerArgs += [
     '-Adagger.formatGeneratedSource=disabled'
     ]C
     }B
     afterEvaluate {
     extensions.findByName('kapt')?.arguments {
     arg("dagger.formatGeneratedSource", "disabled")
     }D
     }C
     }A
     

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171. View Slide

172. allprojects {
     tasks.withType(JavaCompile).all {
     options.compilerArgs += [
     '-Adagger.formatGeneratedSource=disabled'
     ]C
     }B
     afterEvaluate {
     extensions.findByName('kapt')?.arguments {
     arg("dagger.formatGeneratedSource", "disabled")
     }D
     }C
     }A
     

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173. allprojects {
     tasks.withType(JavaCompile).all {
     options.compilerArgs += [
     '-Adagger.formatGeneratedSource=disabled',
     '-Adagger.gradle.incremental=enabled'
     ]C
     }B
     afterEvaluate {
     extensions.findByName('kapt')?.arguments {
     arg("dagger.formatGeneratedSource", "disabled")
     arg("dagger.gradle.incremental", "enabled")
     }D
     }C
     }A
     

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176. View Slide

177. View Slide

178. View Slide

179. View Slide

180. View Slide

181. View Slide

182. View Slide

183. ButterKnife.bind(this)
     

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184. ButterKnife.bind(this)
     class ButterKnife {
     static Unbinder bind(Activity target) {
     // Class.forName lookup…
     }
     }
     butterknife-runtime.aar
     

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185. ButterKnife.bind(this)
     class ButterKnife {
     static Unbinder bind(Activity target) {
     // Reflection implementation…
     }
     }
     butterknife-reflect.aar
     class ButterKnife {
     static Unbinder bind(Activity target) {
     // Class.forName lookup…
     }
     }
     butterknife-runtime.aar
     

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186. dependencies {
     if (properties.containsKey('android.injected.invoked.from.ide')) {
     implementation 'com.jakewharton:butterknife-reflect:9.0.0-rc1'
     } else {
     implementation 'com.jakewharton:butterknife:9.0.0-rc1'
     kapt 'com.jakewharton:butterknife-compiler:9.0.0-rc1'
     }B
     }A
     

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187. dependencies {
     if (properties.containsKey('android.injected.invoked.from.ide')) {
     implementation 'com.jakewharton:butterknife-reflect:9.0.0-rc1'
     } else {
     implementation 'com.jakewharton:butterknife:9.0.0-rc1'
     kapt 'com.jakewharton:butterknife-compiler:9.0.0-rc1'
     // or 'annotationProcessor'…
     }B
     }A
     

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188. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     

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189. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = DaggerAppComponent.builder()
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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190. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = DaggerAppComponent.builder()
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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191. class DaggerReflect {
     }A
     

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192. class DaggerReflect {
     static B builder(Class builderClass) {
     }B
     }A
     

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193. class DaggerReflect {C
     static B builder(Class builderClass) {
     return (B) Proxy.newProxyInstance(
     builderClass.getClassLoader(),
     new Class[] { builderClass },
     ComponentBuilderInvocationHandler.create(builderClass));
     }B
     }A
     

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194. class DaggerReflect {C
     static B builder(Class builderClass) {
     return (B) Proxy.newProxyInstance(
     builderClass.getClassLoader(),
     new Class[] { builderClass },
     ComponentBuilderInvocationHandler.create(builderClass));
     }B
     }A
     

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195. class DaggerReflect {C
     static B builder(Class builderClass) {
     return (B) Proxy.newProxyInstance(
     builderClass.getClassLoader(),
     new Class[] { builderClass },
     ComponentBuilderInvocationHandler.create(builderClass));
     }B
     }A
     

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196. class DaggerReflect {
     static C create(Class componentClass) {
     return (C) Proxy.newProxyInstance(
     componentClass.getClassLoader(),
     new Class[] { componentClass },
     ComponentInvocationHandler.create(componentClass));
     }C
     static B builder(Class builderClass) {
     return (B) Proxy.newProxyInstance(
     builderClass.getClassLoader(),
     new Class[] { builderClass },
     ComponentBuilderInvocationHandler.create(builderClass));
     }B
     }A
     

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197. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = DaggerAppComponent.builder()
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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198. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = DaggerAppComponent.builder()
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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199. final class DaggerAppComponent {
     }A
     

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200. final class DaggerAppComponent {
     static AppComponent.Builder builder() {
     return DaggerReflect.builder(AppComponent.Builder.class);
     }B
     }A
     

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201. final class DaggerAppComponent {
     static AppComponent create() {
     return DaggerReflect.create(AppComponent.class);
     }C
     static AppComponent.Builder builder() {
     return DaggerReflect.builder(AppComponent.Builder.class);
     }B
     }A
     

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202. DaggerAppComponent.builder()
     

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203. DaggerAppComponent.builder()
     final class DaggerAppComponent {
     static AppComponent.Builder builder() {
     // real Dagger implementation…
     }B
     }A
     dagger-compiler.jar + dagger.jar
     

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204. DaggerAppComponent.builder()
     final class DaggerAppComponent {
     static AppComponent.Builder builder() {
     return DaggerReflect.builder(
     AppComponent.Builder.class);
     }B
     }A
     dagger-reflect.jar
     final class DaggerAppComponent {
     static AppComponent.Builder builder() {
     // real Dagger implementation…
     }B
     }A
     dagger-compiler.jar + dagger.jar
     

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205. dagger-compiler.jar
     dagger.jar
     dagger-reflect.jar
     

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206. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = DaggerAppComponent.builder()
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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207. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = DaggerReflect.builder(AppComponent.Builder::class)
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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208. class Dagger {
     }A
     

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209. class Dagger {
     static B builder(Class builderClass) {
     }B
     }A
     

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210. class Dagger {
     static B builder(Class builderClass) {
     return DaggerReflect.builder(builderClass);
     }B
     }A
     

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211. class Dagger {
     static B builder(Class builderClass) {
     return DaggerReflect.builder(builderClass);
     }B
     }A
     class Dagger {
     }A
     

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212. class Dagger {
     static B builder(Class builderClass) {
     return DaggerReflect.builder(builderClass);
     }B
     }A
     class Dagger {
     static B builder(Class builderClass) {
     }B
     }A
     

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213. class Dagger {
     static B builder(Class builderClass) {
     return DaggerReflect.builder(builderClass);
     }B
     }A
     class Dagger {
     static B builder(Class builderClass) {
     return builderClass.getMethod("builder").invoke(null);
     }B
     }A
     

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214. class Dagger {
     static B builder(Class builderClass) {
     return DaggerReflect.builder(builderClass);
     }B
     }A
     class Dagger {
     static B builder(Class builderClass) {
     return builderClass.getMethod("builder").invoke(null);
     }B
     }A
     dagger-reflect.jar
     dagger-codegen.jar
     

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215. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = DaggerReflect.builder(AppComponent.Builder::class)
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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216. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = Dagger.builder(AppComponent.Builder::class)
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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217. @Component(modules = [AppModule::class])
     interface AppComponent {
     fun foo(): Foo
     fun bar(): Bar
     fun thermosiphon(): Thermosiphon
     @Component.Builder
     interface Builder {
     @BindsInstance fun apiKey(@ApiKey apiKey: String)
     fun build(): AppComponent
     }B
     }A
     val component = Dagger.builder(AppComponent.Builder::class)
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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218. val component = Dagger.builder(AppComponent.Builder::class)G
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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219. val component = AppComponent.Builder::class.builder()G
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     

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220. val component = AppComponent.Builder::class.builder()G
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     // dagger-reflect:
     inline fun KClass.builder(): B = DaggerReflect.builder(java)
     

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221. val component = AppComponent.Builder::class.builder()G
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     // dagger-reflect:
     inline fun KClass.builder(): B = DaggerReflect.builder(java)
     // dagger-codegen:
     inline fun KClass.builder(): B =
     throw UnsupportedOperationException("…")
     

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222. val component = AppComponent.Builder::class.builder()G
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     // dagger-reflect:
     inline fun KClass.builder(): B = DaggerReflect.builder(java)
     // dagger-codegen:
     inline fun KClass.builder(): B =
     throw UnsupportedOperationException("…")
     // Generated from dagger-codegen-compiler:
     @JvmName("builderAppComponent")
     inline fun KClass.builder() = AppComponent.builder()
     

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223. val component = AppComponent.Builder::class.builder()G
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     // dagger-reflect:
     inline fun KClass.builder(): B = DaggerReflect.builder(java)
     // dagger-codegen:
     inline fun KClass.builder(): B =
     throw UnsupportedOperationException("…")
     // Generated from dagger-codegen-compiler:
     @JvmName("builderAppComponent")
     inline fun KClass.builder() = AppComponent.builder()
     

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224. AppComponent.Builder::class.builder()G
     val component =
     .apiKey("IDt0n5RoTAc0l3CiVR3sRn13d0kdNaN1oK")
     .build()
     // dagger-reflect:
     inline fun KClass.builder(): B = DaggerReflect.builder(java)
     // dagger-codegen:
     inline fun KClass.builder(): B =
     throw UnsupportedOperationException("…")
     // Generated from dagger-codegen-compiler:
     @JvmName("builderAppComponent")
     inline fun KClass.builder() = AppComponent.builder()
     AppComponent.builder()
     

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225. View Slide

226. View Slide

227. Helping
     Dagger
     Help
     You
     @JakeWharton
     

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