Why classes define behavior and state in Kotlin - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a class named Person.

Kotlin

class [1] {
    var name: String = ""
}

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

AMyClass

Bperson

CData

DPerson

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase or unrelated class names.

The class name should start with a capital letter and match the concept, so Person is correct.

2fill in blank

medium

Complete the code to add a function greet() that prints a greeting.

Kotlin

class Person {
    var name: String = ""
    fun [1]() {
        println("Hello, $name!")
    }
}

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

Agreet

BsayHello

Chello

DprintGreeting

Attempts:

3 left

💡 Hint

Common Mistakes

Using different function names that don't match the instruction.

The function name greet matches the instruction to add a greet() function.

3fill in blank

hard

Fix the error in the code to correctly initialize the name property via constructor.

Kotlin

class Person([1]: String) {
    var name: String = name
}

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

Avar name

Bname

Cval name

Dval n

Attempts:

3 left

💡 Hint

Common Mistakes

Not declaring the constructor parameter as a property.

Using val name: String in the constructor declares and initializes the property properly.

4fill in blank

hard

Fill both blanks to create a class with a mutable property and a function that updates it.

Kotlin

class Counter {
    var count: Int = [1]
    fun increment() {
        count [2] 1
    }
}

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

A0

B+=

C-=

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-=' instead of '+='.

Starting count at 1 instead of 0.

The count starts at 0 and is increased by 1 using the '+=' operator.

5fill in blank

hard

Fill all three blanks to define a class with a property, a constructor, and a method that returns a greeting.

Kotlin

class Person([1]: String) {
    val name: String = [2]
    fun greet(): String {
        return "Hello, $[3]!"
    }
}

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

Aname

DpersonName

Attempts:

3 left

💡 Hint

Common Mistakes

Using different names causing errors or confusion.

The constructor parameter, property, and string interpolation all use the same name 'name' to connect the data.