API interface definition in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a Retrofit API interface method for a GET request.

Android Kotlin

interface ApiService {
    @GET("users")
    fun getUsers(): [1]<List<User>>
}

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

ACall

BResponse

CDeferred

DObservable

Attempts:

3 left

💡 Hint

Common Mistakes

Using Response instead of Call causes compilation errors.

Using Deferred requires additional coroutine setup.

The Retrofit interface method returns a Call object for asynchronous requests.

2fill in blank

medium

Complete the code to define a POST request method with a JSON body parameter.

Android Kotlin

interface ApiService {
    @POST("posts")
    suspend fun createPost(@Body [1]: Post): Response<Post>
}

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ApostData

BpostBody

Cbody

Dpost

Attempts:

3 left

💡 Hint

Common Mistakes

Using ambiguous parameter names reduces code clarity.

Forgetting the @Body annotation causes runtime errors.

The parameter name can be anything, but post is a clear and common choice.

3fill in blank

hard

Fix the error in the interface method to correctly define a query parameter.

Android Kotlin

interface ApiService {
    @GET("search")
    suspend fun searchUsers(@Query("query") [1]: String): Response<List<User>>
}

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

AsearchTerm

BqueryString

Cquery

Dterm

Attempts:

3 left

💡 Hint

Common Mistakes

Using a parameter name different from the query key without specifying it causes errors.

Omitting the @Query annotation breaks the query parameter.

The parameter name must match the query key or be clearly related; here, 'query' matches the @Query key.

4fill in blank

hard

Fill both blanks to define a header parameter and a path parameter in the API interface.

Android Kotlin

interface ApiService {
    @GET("users/[1]")
    suspend fun getUser(@Header("Authorization") [2]: String): Response<User>
}

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

AuserId

BauthToken

Ctoken

Did

Attempts:

3 left

💡 Hint

Common Mistakes

Using ambiguous names for path or header parameters.

Forgetting to annotate parameters with @Header or path placeholder.

The path parameter is typically named userId to identify the user, and the header parameter for authorization is commonly named authToken.

5fill in blank

hard

Fill all three blanks to define a PATCH request with path, header, and body parameters.

Android Kotlin

interface ApiService {
    @PATCH("posts/[1]")
    suspend fun updatePost(@Header("Authorization") [2]: String, @Body [3]: Post): Response<Post>
}

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

ApostId

BauthHeader

Cpost

Dtoken

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up parameter names causing confusion.

Omitting necessary annotations like @Body or @Header.

The path parameter is postId to identify the post, the header parameter is token for authorization, and the body parameter is post representing the updated post data.