Control flow (if, for, while, switch) in Flutter - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does an if statement do in Flutter?

An if statement checks a condition and runs code only if that condition is true. It helps the app decide what to do next.

beginner

How does a for loop work in Flutter?

A for loop repeats a block of code a set number of times. It’s like telling the app to do something again and again.

intermediate

What is the purpose of a while loop?

A while loop keeps running code as long as a condition stays true. It’s useful when you don’t know how many times you need to repeat beforehand.

intermediate

Explain the switch statement in Flutter.

A switch statement checks a value and runs code for the matching case. It’s like choosing a path based on different options.

beginner

Why is control flow important in mobile apps?

Control flow lets apps make decisions and repeat tasks. It helps apps respond to user actions and show the right screens or data.

What will this if statement do if the condition is false?<br>

if (isLoggedIn) {
  showHomePage();
}

A Restart the app

B Show the home page

C Show an error

D Do nothing

If the condition is false, the code inside the if block does not run, so nothing happens.

How many times will this for loop run?<br>

for (int i = 0; i < 3; i++) {
  print(i);
}

A 3 times

B 2 times

C 1 time

D Infinite times

The loop runs while i is less than 3, so it runs 3 times with i values 0, 1, and 2.

What happens if the while loop condition is never true?

A The loop runs once

B The loop does not run at all

C The loop runs forever

D The app crashes

If the condition is false at the start, the while loop does not run any code.

Which statement best describes a switch?

A Repeats code forever

B Checks if a condition is true

C Chooses code to run based on a value

D Stops the app

A switch selects which block of code to run depending on the value it checks.

Why use control flow in a mobile app?

A To make decisions and repeat tasks

B To change the app icon

C To speed up the internet

D To store user data

Control flow helps the app decide what to do and repeat actions when needed.

Describe how an if statement controls app behavior.

Think about how the app decides to do something only sometimes.

Explain the difference between a for loop and a while loop.

One counts how many times, the other checks a condition each time.