How to use state restoration properly here ?

Question

Hi, I'm trying to save the state of some switches and restore it when the app launches again but when I wrote this :

override func encodeRestorableState(with coder: NSCoder) {

super.encodeRestorableState(with: coder)

coder.encode(Int32(self.runSwitch1.state.rawValue), forKey: CodingKey.Protocol)

}

I got this error : Cannot convert value of type 'CodingKey.Protocol.Type' to expected argument type 'String'

What should I do ?

367

Posted by

Dave19

Reply

Answer 1

You seem to be mixing up Swift’s

Codable

(which is where

CodingKey

comes from) with the traditional Cocoa

NSCoder

. These are very different beasts.

encode(_:forKey:)

is an

NSCoder

method, and it takes a string for the

forKey

parameter. Traditionally you’d use something that describes the meaning of the encoded item, like

runSwitch1State

.

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Posted by

eskimo

Answer 2

I'm pretty new to swift and I don't understand ,how should I rewrite my code ?

Posted by

Dave19

Answer 3

The second parameter to

encode(_:forKey:)

has to be a string.

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Posted by

eskimo

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