How to declare custom object eg. Timer in codable class

Question

I'm facing an issue with codable. I'm not able to understand how to init custom timer object in codable class.

    class ShelfItem: Codable {

      var objTimer = Timer()

or i try to do it like

     // var objTimer: Timer()
    }

but it show me the error that is "Type 'ShelfItem' does not conform to protocol 'Encodable'"

The var objTimer = Timer() doesn’t make sense (a timer with no handler and no specified time to fire). And var objTimer: Timer() is just syntactically incorrect. But let’s set that aside and ask what you’re expecting to be encoded: As vadian said, it doesn’t make sense to encode/decode a Timer, itself, so you’d either exclude it from coding or take the unusual step to encode/decode enough so the timer could be reconstituted later (which is a strange notion with timers). Perhaps you can describe why you’re trying to encode/decode a timer and describe what you’re hoping to achieve. — Rob

vadian vadian · Accepted Answer · 2019-06-15T07:06:00

It makes no sense to en-/decode a Timer object.

To exclude objTimer from encoding add CodingKeys for the other properties and omit objTimer.

Simple example (in most cases you don't even need a class)

struct ShelfItem : Codable {
    let name : String
    var timer : Timer

    private enum CodingKeys : String, CodingKey { case name }

    init(from decoder : Decoder) throws
    {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        name = try container.decode(String.self, forKey: .name)
        timer = Timer()
    }
}

How to declare custom object eg. Timer in codable class

1 Answers