Repository pattern in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a repository interface in Kotlin.

Android Kotlin

interface UserRepository {
    fun getUserById(id: Int): [1]
}

Drag options to blanks, or click blank then click option'

AInt

BString

CBoolean

DUser

Attempts:

3 left

💡 Hint

Common Mistakes

Returning a primitive type like Int or Boolean instead of a User object.

Using String as return type which does not represent a user.

The repository interface defines a method to get a User object by its ID.

2fill in blank

medium

Complete the code to implement the repository interface with a local data source.

Android Kotlin

class LocalUserRepository : UserRepository {
    override fun getUserById(id: Int): [1] {
        // fetch user from local database
        return User(id, "Name")
    }
}

Drag options to blanks, or click blank then click option'

AString

BInt

CUser

DBoolean

Attempts:

3 left

💡 Hint

Common Mistakes

Returning a String or other type instead of User.

Not overriding the method correctly.

The implementation returns a User object as defined in the interface.

3fill in blank

hard

Fix the error in the repository method signature to make it suspendable for coroutine support.

Android Kotlin

interface UserRepository {
    suspend fun getUserById(id: Int): [1]
}

Drag options to blanks, or click blank then click option'

AString

BUser

CUnit

DBoolean

Attempts:

3 left

💡 Hint

Common Mistakes

Changing the return type to Unit or Boolean which does not represent user data.

Removing suspend keyword which is required for coroutine support.

The suspend function must return the User type to support asynchronous fetching.

4fill in blank

hard

Fill both blanks to create a repository method that fetches users from a remote source and returns a list.

Android Kotlin

interface UserRepository {
    suspend fun getAllUsers(): [1]<[2]>
}

Drag options to blanks, or click blank then click option'

AList

BUser

CSet

DString

Attempts:

3 left

💡 Hint

Common Mistakes

Using Set instead of List which is less common for ordered user lists.

Returning String which does not represent user data.

The method returns a list of User objects fetched asynchronously.

5fill in blank

hard

Fill all three blanks to implement a repository method that saves a user and returns a success flag.

Android Kotlin

interface UserRepository {
    suspend fun saveUser(user: [1]): [2]
}

class UserRepositoryImpl : UserRepository {
    override suspend fun saveUser(user: [3]): Boolean {
        // save user logic
        return true
    }
}

Drag options to blanks, or click blank then click option'

AUser

BBoolean

CString

DInt

Attempts:

3 left

💡 Hint

Common Mistakes

Mismatching parameter types between interface and implementation.

Returning String or Int instead of Boolean.

The saveUser method takes a User object and returns a Boolean indicating success.