Data classes in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a data class named User with two properties.

Android Kotlin

data class User(val name: String, val [1]: Int)

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

Aage

Bheight

Cweight

Demail

Attempts:

3 left

💡 Hint

Common Mistakes

Using a property name that does not match the type Int.

Forgetting to declare the property inside the parentheses.

The data class User has two properties: name and age. 'age' is the correct property name for an integer representing the user's age.

2fill in blank

medium

Complete the code to create an instance of the User data class.

Android Kotlin

val user = User(name = "Alice", [1] = 30)

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

Aweight

Bheight

Cemail

Dage

Attempts:

3 left

💡 Hint

Common Mistakes

Using a property name not defined in the data class.

Mixing up property names.

When creating an instance of User, the property 'age' must be assigned an integer value. Here, 30 is assigned to 'age'.

3fill in blank

hard

Fix the error in the copy function call to change the age of the user.

Android Kotlin

val olderUser = user.copy([1] = 31)

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

Aage

Bheight

Cweight

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to change a property not defined in the data class.

Using incorrect property names in the copy function.

The copy function allows creating a new User with some properties changed. To change the age, use 'age = 31'.

4fill in blank

hard

Fill both blanks to define a data class with a default value for age.

Android Kotlin

data class User(val name: String, val age: Int = [1]) {
  fun isAdult() = age [2] 18
}

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

A18

B>

C<

D21

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong comparison operator.

Setting an unrealistic default age.

The default age is set to 18. The function checks if age is greater than 18 to determine adulthood.

5fill in blank

hard

Fill all three blanks to create a data class with a method that returns a greeting message.

Android Kotlin

data class User(val name: String, val age: Int) {
  fun greet() = "Hello, my name is [1] and I am [2] years [3]."
}

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

Aname

Bold

Dage

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing property names with string literals.

Using incorrect words for the greeting.

The greet function uses 'name' and 'age' properties to create a greeting. The word 'old' completes the sentence.