Can you give an example of a situation where the principle of dependency inversion is violated?

The Dependency Inversion Principle states that high-level modules should not depend on low-level modules directly, but both should depend on abstractions.

Example of violation:

If an Android application's Activity directly creates and uses a specific class for data access (for example, a specific repository), then the Activity depends on the concrete implementation rather than on an abstraction (interface). This complicates testing and replacing the implementation.

class UserRepository {
    fun getUser() = "User"
}

class MainActivity : AppCompatActivity() {
    private val userRepository = UserRepository() // Direct dependency on a specific class

    fun showUser() {
        val user = userRepository.getUser()
        // ...
    }
}

Here, the principle is violated because MainActivity depends on the concrete UserRepository rather than on an interface, which makes it difficult to replace or mock the repository.