Why enums constrain values in Kotlin - See It in Action

Why enums constrain values

📖 Scenario: Imagine you are building a simple app that tracks the status of orders in a store. Each order can only have one of a few fixed statuses, like Pending, Shipped, or Delivered. You want to make sure the status can never be set to something invalid by mistake.

🎯 Goal: You will create an enum class in Kotlin to hold the allowed order statuses. Then you will use this enum to assign and print the status of an order, showing how enums help keep values safe and limited.

📋 What You'll Learn

Create an enum class called OrderStatus with values PENDING, SHIPPED, and DELIVERED

Create a variable called currentStatus and set it to OrderStatus.PENDING

Change currentStatus to OrderStatus.SHIPPED

Print the value of currentStatus to show the current order status

💡 Why This Matters

🌍 Real World

Enums are used in apps to keep data clean and predictable, like order statuses, user roles, or traffic light colors.

💼 Career

Understanding enums is important for writing safe, clear code in Kotlin, which is widely used for Android apps and backend services.

1

Create the enum class for order statuses

Create an enum class called OrderStatus with the values PENDING, SHIPPED, and DELIVERED.

Kotlin

// Your code here

Need a hint?

Use enum class OrderStatus { PENDING, SHIPPED, DELIVERED } to define the fixed set of statuses.

2

Create a variable for the current order status

Create a variable called currentStatus and set it to OrderStatus.PENDING.

Kotlin

enum class OrderStatus {
    PENDING,
    SHIPPED,
    DELIVERED
}

// Your code here

Need a hint?

Use var currentStatus = OrderStatus.PENDING to start with the pending status.

3

Change the current status to shipped

Change the variable currentStatus to OrderStatus.SHIPPED.

Kotlin

enum class OrderStatus {
    PENDING,
    SHIPPED,
    DELIVERED
}

var currentStatus = OrderStatus.PENDING

// Your code here

Need a hint?

Assign OrderStatus.SHIPPED to currentStatus to update the status.

4

Print the current order status

Write a println statement to print the value of currentStatus.

Kotlin

enum class OrderStatus {
    PENDING,
    SHIPPED,
    DELIVERED
}

var currentStatus = OrderStatus.PENDING
currentStatus = OrderStatus.SHIPPED

// Your code here

Need a hint?

Use println(currentStatus) to show the current status on the screen.