NEW: My new book Pro SwiftUI is out now – level up your SwiftUI skills today! >>

Project 9 in Hacking with iOS: UIKit Edition

Forums > Books

On page 343, there are two calls to performSelector(onMainThread:with:waitUntilDone:). The first one appears as tableView.performSelector, but the second is simply performSelector. Why do these differ from each other? Is it because the first one is calling UITableView.reloadData?

I ask because Xcode 12.4 complains about the first call ("UITableViewController.tableView must be used from main thread only"). It seems to work in spite of this complaint, but I suspect something has changed in Swift since the book was written, so this code may not be strictly correct any more. If I change tableView.performSelector to a bare performSelector, the code crashes. How can we make the call to assign the reloadData operation to the main thread without a reference to tableView (or is that the wrong idea)?

Thanks!

1      

Hacking with Swift is sponsored by Play

SPONSORED Play is the first native iOS design tool created for designers and engineers. You can install Play for iOS and iPad today and sign up to check out the Beta of our macOS app with SwiftUI code export. We're also hiring engineers!

Click to learn more about Play!

Sponsor Hacking with Swift and reach the world's largest Swift community!

Archived topic

This topic has been closed due to inactivity, so you can't reply. Please create a new topic if you need to.

All interactions here are governed by our code of conduct.

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.