If as an expression returning value in Kotlin - Mini Project: Build & Apply

Using If as an Expression Returning Value in Kotlin

📖 Scenario: Imagine you are creating a simple program that decides what message to show based on the temperature outside. You want to use Kotlin's if expression to choose the message.

🎯 Goal: Build a Kotlin program that uses if as an expression to assign a message based on a temperature value.

📋 What You'll Learn

Create an integer variable called temperature with the value 15

Create a string variable called message that uses if as an expression to set its value

Use if to check if temperature is greater than 20

If true, message should be "It's warm outside!"

If false, message should be "It's cold outside!"

Print the message variable

💡 Why This Matters

🌍 Real World

Using <code>if</code> as an expression helps in many real-world apps where decisions affect what data or message to show.

💼 Career

Understanding expressions like <code>if</code> in Kotlin is important for writing clean, efficient code in Android app development and backend services.

1

Create the temperature variable

Create an integer variable called temperature and set it to 15.

Kotlin

# Create an integer variable called temperature and set it to 15
// Your code here

Need a hint?

Use val temperature = 15 to create the variable.

2

Create the message variable using if expression

Create a string variable called message that uses if as an expression to set its value. Use if (temperature > 20) to assign "It's warm outside!" if true, otherwise "It's cold outside!".

Kotlin

val temperature = 15
// Create a string variable message using if expression
// Your code here

Need a hint?

Use val message = if (temperature > 20) "It's warm outside!" else "It's cold outside!".

3

Print the message

Write a println statement to print the message variable.

Kotlin

val temperature = 15
val message = if (temperature > 20) "It's warm outside!" else "It's cold outside!"
// Print the message variable
// Your code here

Need a hint?

Use println(message) to show the message on the screen.

4

Run the program and see the output

Run the program and observe the output. It should print "It's cold outside!" because the temperature is 15.

Kotlin

val temperature = 15
val message = if (temperature > 20) "It's warm outside!" else "It's cold outside!"
println(message)
// Run the program to see the output

Need a hint?

Check that the output matches exactly: "It's cold outside!"