Explain the mechanism of Scope in Dagger and how it manages the lifetime of objects.

Dagger Scope is used to manage the lifetime and scope of dependencies created. The Scope annotation allows limiting the creation of an object to a single instance within a certain lifecycle.

For example, if you have a scope @Singleton, then the object with this scope will be created once for the entire lifecycle of the component (usually the application). If the scope is, for example, @ActivityScope, then the object will be created once for the lifetime of the Activity.

Working mechanism:

• Scopes are linked to Dagger components.
• When a dependency with a certain scope is requested, Dagger checks if an instance already exists in that scope.
• If it exists — it returns it; if not — it creates a new one and saves it for reuse.

This allows efficient resource management and guarantees that objects with a certain scope will not be recreated unnecessarily.

Example:

@Scope
@Retention(AnnotationRetention.RUNTIME)
annotation class ActivityScope

@ActivityScope
@Component(modules = [SomeModule::class])
interface ActivityComponent {
    fun inject(activity: SomeActivity)
}

Here, all dependencies with the @ActivityScope annotation will live as long as the ActivityComponent does.