Why do I keep getting "Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value" ?! Isn't Swift supposed to be easy?
What does nil mean? Why finding nil causes the program to crash?
You asked online and some people suggested using if let and guard let to prevent the crash, but what
You Googled online, found some articles which provide fixes, but you still don't understand why those fixes
Wouldn't it be good if those funky symbols ("?", "!") doesn't exist? Instead of spending hours fighting with errors, you could focus on the fun part - building features for your app!
What if you could focus on the fun part - building
What if you are able to navigate through the symbols (
You could finish the app idea that you have been wanting to work on, submit it to the App Store, and have a better resume for
Understand how and why Optionals works and use it to your advantage
When we don't understand how something works, we tend to get intimidated by it (eg: High school maths, how
Learn the purpose of
Optionals, and how to use them to aide your app development process with the book 'Understanding Optionals'
This book will cover :
- How does
- Unwrapping Optionals forcefully
- How to handle
optionalssafely, using if let and chaining
- Providing default values when the expected values aren't there
- Explaining various jargons (eg: optional binding, implicitly unwrapped
- Solving 'Unexpectedly found nil' error which relates to Storyboard UI (eg:
nameLabel :UILabel! )
- Treating an object as another type safely
This bundle pack also includes two extra booklet which explains :
- How to use 'guard' statement to simplify optional handling
- How delegate works (+ 2 Xcode playground file to demonstrate how it works)
+ 1 Optional Cheatsheet that you can quickly refer to when you are not sure what the jargons (optional binding, implicitly unwrapped optional etc) means.
1 PDF / ePub of Understanding
1 PDF / ePub of Simplify Optional Handling using Guard book
1 PDF / ePub of Explaining Delegate book
2 Xcode Playground file to help demonstrate the delegate concept
1 PDF Cheatsheet of Optionals
Each book is concise and tightly focused on getting you to understand the concept of
You can get two sample chapters of this book here.
If using this book does not help you learn and understand
Simplify Optional handling using Guard
- Size5.07 MB
- Understanding OptionalsPDF
- Simplify Optional handling using GuardPDF
- Explaining DelegatePDF
- dataSourceButtonPlayground File
- delegateButtonPlayground File
- Optional CheatsheetPDF