"Discover Observation in SwiftUI" session has a bug

Question

ericagredo OP

Created Jun ’23

Replies 3

Boosts 1

Views 1.2k

Participants 4

They provide an example on using @Observable in minute 5:14 :

@Observable class Account { var userName: String? }

However, if you put that in Xcode this gives an error: @Observable requires property 'userName' to have an initial value (from macro 'Observable')

Anyone else seeing this?

Boost

Answer 1

dmalicke OP

Jun ’23

Yes, I'm seeing this too.

var timer: AnyCancellable? is throwing the same error:

@Observable requires property 'timer' to have an initial value (from macro 'Observable')

EDIT: In my case making the timer: AnyCancellable? = nil removes the error

Here's my code:

@Observable class SubscriberViewModel {
    
    public var count: Int = 0
    var timer: AnyCancellable?
    
    func setupTimer() {
        timer = Timer
            .publish(every: 1, on: .main, in: .common)
            .autoconnect()
            .sink { [weak self] _ in
                self?.count += 1
            }
    }
}

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Answer 2

AndyJJ OP

Jun ’23

Does it help to do var userName: String? = nil?

0

Answer 3

DTS Engineer OP

Apple

Jun ’23

Does it help to do [initialise it to] nil?

Yep. This is more fallout from the issued discussed in this thread.

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