Dagger 2 component not generated

Question

In my module, in my base Application class

component = DaggerCompClassComponent.builder()
                .classModule(new ModuleClass()).build();

Answer 1

In build.gradle's app, you need to add necessary dependencies for Dagger to generate corresponding classes, as below:

  implementation 'com.google.dagger:dagger-android:2.21'
  implementation 'com.google.dagger:dagger-android-support:2.21' // if you use the support libraries
  annotationProcessor 'com.google.dagger:dagger-android-processor:2.21'
  annotationProcessor 'com.google.dagger:dagger-compiler:2.21'

you should change dagger version which you are using.

refer full dagger document in this

Answer 2

When developing on Kotlin, you should add the following lines next to their annotationProcessor counterparts:

kapt 'com.google.dagger:dagger-android-processor:2.15'
kapt 'com.google.dagger:dagger-compiler:2.15'

and add apply plugin: 'kotlin-kapt' at the start of the same file.

That section looks like this for me:

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-kapt' // <- Add this line
apply plugin: 'io.fabric'

Answer 3

In my case it wasn't being created only in Instrumentation Testing, because I was missing

kaptAndroidTest "com.google.dagger:dagger-compiler:$rootProject.daggerVersion"

Of course I'm using Kotlin and $rootProject.daggerVersion is a property on my base build file. You can replace for whatever version or gradle dependency you desire and are missing.

Answer 4

I solved it by editing my dagger dependencies to this:

 implementation "com.google.dagger:dagger:${versions.dagger}"
 kapt "com.google.dagger:dagger-compiler:${versions.dagger}"

Answer 5

Update (March 29, 2020)

Inside your app-level build.gradle inside dependencies block, add these lines:

     //dagger2
     api 'com.google.dagger:dagger:2.24'
     api 'com.google.dagger:dagger-android:2.24'
     api 'com.google.dagger:dagger-android-support:2.24'

     annotationProcessor 'com.google.dagger:dagger-compiler:2.24'
     kapt 'com.google.dagger:dagger-compiler:2.24'

     annotationProcessor 'com.google.dagger:dagger-android-processor:2.24'
     kapt 'com.google.dagger:dagger-android-processor:2.24'

     compileOnly 'javax.annotation:jsr250-api:1.0'
     implementation 'javax.inject:javax.inject:1'

Inside android block of app-level build.gradle,

kapt {
        generateStubs = true
    }

At the top of the app-level build.gradle, Do this in exactly below order.

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-kapt'
apply plugin: 'kotlin-android-extensions'

Finally, You need to configure Annotation Process as provided in the screenshot below. You can do this File>Other Settings>Settings for New Projects>search"Annotation processor"

After this, do from Menu Build > Rebuild. You are done!

Test:

@Component
public interface ApplicationComponent {

}

Now, you can use DaggerApplicationComponent that was generated at compile-time for your ApplicationComponent interface.

public class MyApplication extends Application {

    ApplicationComponent applicationComponent = DaggerApplicationComponent.create();


}

Answer 6

If Dagger2 can not generate its components it means that your code have some errors with Scopes/Modules. Check our your @Provides/Inject methods.

UPD:

You should inject your components into cases where you need instances of classes provided by module.

like

inject(MainActivity main);