Enum class declaration in Kotlin - Mini Project: Build & Apply

Enum class declaration

📖 Scenario: Imagine you are creating a simple app that needs to handle different types of weather conditions.

🎯 Goal: You will create an enum class in Kotlin to represent different weather types.

📋 What You'll Learn

Create an enum class named Weather with specific weather types

Add a variable to hold a current weather value

Use the enum class in a simple function

Print the current weather

💡 Why This Matters

🌍 Real World

Enum classes help represent fixed sets of related constants, like days, states, or categories, making code clearer and safer.

💼 Career

Understanding enum classes is important for Kotlin developers working on Android apps or backend services where fixed sets of options are common.

1

Create the enum class

Create an enum class called Weather with these exact entries: SUNNY, CLOUDY, RAINY, SNOWY.

Kotlin

# Create enum class Weather with SUNNY, CLOUDY, RAINY, SNOWY
// Your code here

Need a hint?

Use the enum class keyword followed by the name Weather. List the weather types separated by commas inside curly braces.

2

Create a variable for current weather

Create a variable called currentWeather of type Weather and set it to Weather.SUNNY.

Kotlin

enum class Weather {
    SUNNY, CLOUDY, RAINY, SNOWY
}

// Create variable currentWeather of type Weather and set it to Weather.SUNNY
// Your code here

Need a hint?

Use val currentWeather: Weather = Weather.SUNNY to create the variable.

3

Write a function to describe the weather

Write a function called describeWeather that takes a parameter weather of type Weather and returns a String. Use a when expression on weather to return these exact strings: "It's sunny today!" for Weather.SUNNY, "It's cloudy today." for Weather.CLOUDY, "It's raining." for Weather.RAINY, and "Snow is falling." for Weather.SNOWY.

Kotlin

enum class Weather {
    SUNNY, CLOUDY, RAINY, SNOWY
}

val currentWeather: Weather = Weather.SUNNY

// Write function describeWeather(weather: Weather): String using when expression
// Your code here

Need a hint?

Use a when expression to check the weather parameter and return the matching string.

4

Print the current weather description

Print the result of calling describeWeather with currentWeather.

Kotlin

enum class Weather {
    SUNNY, CLOUDY, RAINY, SNOWY
}

val currentWeather: Weather = Weather.SUNNY

fun describeWeather(weather: Weather): String {
    return when (weather) {
        Weather.SUNNY -> "It's sunny today!"
        Weather.CLOUDY -> "It's cloudy today."
        Weather.RAINY -> "It's raining."
        Weather.SNOWY -> "Snow is falling."
    }
}

// Print the description of currentWeather
// Your code here

Need a hint?

Use println(describeWeather(currentWeather)) inside a main function to print the weather description.