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Inject into Activity

Koject provides additional support for injecting into Activities.

Setup for Activity​

The following dependency is required to take advantage of the additional support.

dependencies {
    implementation("com.moriatsushi.koject:koject-android-activity:1.3.0")
}

Please also refer to the Setup document.

Basic usage​

You can use the ComponentActivity.inject() or ComponentActivity.lazyInject() methods to inject any provided type.

@Provides
@Singleton
class Repository

@Provides
class Controller(
    private val repository: Repository
)
class MyActivity: ComponentActivity {
    val controller: Controller by lazyInject()
}

Inject Activity / Context into other types​

Koject defines the @ActivityComponent and adding this annotation restricts it to be injectable only to Activity or ActivityComponent types.

@ActivityComponent
class ActivityHelper
@ActivityComponent
class ActivityHelperHolder(
    val helper: ActivityHelper // can be injected
)
class MyActivity: ComponentActivity {
    val helper: ActivityHelper by lazyInject() // can be injected
}

ActivityComponent types can be injected with androidx.activity.ComponentActivity and android.app.Activity.

@ActivityComponent
class ActivityHelper(
    val activity: ComponentActivity // can be injected
)

Similarly, android.content.Context can be injected by adding an @ActivityContext qualifier.

@ActivityComponent
class ActivityHelper(
    @ActivityContext
    val context: Context // activity's context
)

Inject Activity's CoroutineScope​

The ActivityComponent type can also inject an activity-scoped CoroutineScope. The CoroutineScope requires an @ActivityCoroutineScope qualifier.

@ActivityComponent
class ActivityHelper(
    @ActivityCoroutineScope
    val coroutineScope: CoroutineScope // same as ComponentActivity.lifecycleScope
)
LINK

Check the Android components documentation for all available components for Android.