You want to fetch JSON data from a web API and decode it into a Swift struct using URLSession. Which sequence correctly performs this task?

hard📝 Application Q8 of 15

iOS Swift - Networking

You want to fetch JSON data from a web API and decode it into a Swift struct using URLSession. Which sequence correctly performs this task?

ACreate URL, start dataTask, decode JSON in completion handler, update UI on main thread

BCreate URL, decode JSON, start dataTask, update UI on background thread

CStart dataTask, create URL, decode JSON on main thread, update UI

DCreate URL, start dataTask, update UI directly in background thread

Step-by-Step Solution

Solution:

Step 1: Create the URL
Initialize a valid URL object for the API endpoint.
Step 2: Start the data task
Use URLSession.shared.dataTask(with:) to fetch data asynchronously.
Step 3: Decode JSON in completion handler
Use JSONDecoder to decode the data inside the completion handler.
Step 4: Update UI on main thread
Dispatch UI updates to the main thread using DispatchQueue.main.async.
Final Answer:
Create URL, start dataTask, decode JSON in completion handler, update UI on main thread correctly describes the proper sequence.
Quick Check:
Decode JSON in completion, update UI on main thread [OK]

Quick Trick: Decode JSON in completion, update UI on main thread [OK]

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