iOS Developer Interview Questions
What does the Codable protocol do?
Suggested approach: This protocol was introduced in Swift 4 to let us quickly and safely convert custom Swift types to and from JSON, XML, and similar.
For bonus points talk about customization points such as key and date decoding strategies, the CodingKey protocol, and more, so that you're able to show you can handle a range of input and output styles.
Estimated difficulty: Easy
See the full list of iOS interview questions
Important notes
- There are over 150 interview questions in the system. Once you've read the question and come up with a suitable answer, try reading my suggested approach and see if it helps you add more detail.
- These questions are not designed to be hard; a good interviewer is more interested in generating discussion that lets your ability and interests shine through.
- If you answer a question with "yes" or "no" you've missed the point – interviewers prefer you to provide reasoning, explanation, or detail, so try to elaborate with examples!
- If you're looking for detailed technical questions about the language, you should try my Swift tests instead – there are multiple challenges that will work your brain hard.
- For a whole series of coding challenges, I wrote the perfect book for you: Swift Coding Challenges.
Related questions
-
What is the difference between the
Float,Double, andCGFloatdata types? - What does it mean when we say “strings are collections in Swift”?
- What's the difference between a value type and a reference type?
- What are tuples and why are they useful?
-
What’s the importance of key decoding strategies when using
Codable?
