Property Observers

Lesson in the Swift & Swift UI Roadmap · Stage 24: What is SwiftUI

Last updated 14 September 2026

What is Property Observers?

Property observers in Swift allow you to monitor and respond to changes in a property's value. You can define code that will be executed before (willSet) or after (didSet) a property's value is set. This is useful for tasks like updating the user interface, performing calculations based on the new value, or validating data.

Study this in the interactive course See the whole Swift & Swift UI roadmap

Free resources to learn Property Observers

Official docsProperty Observers
VideoProperty observers: didSet – 7 Swifty Words, part 5

Property Observers: common questions

Can I learn Property Observers in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Property Observers in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this Property Observers tutorial for beginners?

It is lesson 53 of 156 in the free Swift & Swift UI roadmap, in stage 24, What is SwiftUI. If you are new to Swift & Swift UI, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.