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Swift calculator


I have 2 questions about the calculator I'm building in swift:

  1. I don't know how to program the , button and the π button
  2. I can't figure out which constraints to add to all the buttons...

The Xcode files are in GitHub: https://github.com/LucasPeters/Question-swift-calculator

Thank you

Jeff McDivitt
Jeff McDivitt
23,970 Points

Your are missing the assets folder in your project; therefore, nothing can be viewed and we cannot assist you. Please upload the complete project

2 Answers

I'm sorry about that... I uploaded the right files: https://github.com/LucasPeters/Question-swift-calculator/tree/master

Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

First, I really like your code. It could use some cleaning, but as far as how you are handling types and calculations, I really like it.

To handle the input for Pi, the number types (Int, Float, Double, etc) have a static property for each call pi, so your handler for that button press would look something like this:

@IBAction func btnPiPressed(_ sender: UIButton) {

Th decimal press handler will do about the same thing, all you do is use '.' as the string:

@IBAction func btnDecimalPress(_ sender: UIButton) {

As far as the buttons go, using an image as the background is an interesting idea, but that will be a complete pain when trying to align things with it. The better way to do it is to color all the buttons background and adding constraints. This is a bit involved so I will link to a GitHub repo that you can look at the Storyboard:


If what I did doesn't make sense, don't worry, you'll learn about auto-layout in this course.