Scope aliases

Why would you need a scope alias?

Scope aliases are useful during a migration to Hilt if you have a lot of code using a previous scope annotation that you now want to switch to one of the Hilt provided scope annotations. Depending on the size of your codebase, this could mean changing the scope annotation in a lot of places. By adding a scope alias, you can make the changes incrementally.

Using a scope alias just tells Dagger and Hilt that these scope annotations should be treated the same.

How to use @AliasOf

If you mark a scope annotation with @AliasOf, it will tell Hilt that the annotated scope annotation should be treated the same as the one in the value of the @AliasOf annotation. The annotation value must be a scope annotation used in a @DefineComponent type so that Hilt knows what to do with it.

For example, the following takes a previous @MyActivityScoped annotation and makes it equivalent to the Hilt @ActivityScoped. Now it should be easy to incrementally replace @MyActivityScoped with the Hilt version.

public @interface MyActivityScoped {}
annotation class MyActivityScoped {}