swiftinitializationconvenience-methods

Whats wrong with my convenience initializer when I attempt to call self.init?


I wrote the code below. The error I'm getting is at the end of my convenience initializer when I attempt to call self.init. What's wrong with my logic or syntax? Or how would I debug this? The error Xcode is giving is "cannot invoke with an argument list of type".

Thank you for any help on this

import Foundation
import UIKit

class Item: NSObject {

    var name: String
    var valueInDollars: Int
    var serialNumber: String?
    let dateCreated: NSDate
    var stolen: Bool?

    init(name: String, valueInDollars: Int, serialNumber: String?, dateCreated: NSDate, stolen: Bool?) {
        self.name = name
        self.valueInDollars = valueInDollars
        self.serialNumber = serialNumber
        self.dateCreated = NSDate()
        self.stolen = stolen

        //below why did I have to call super.init for this custom class that inherits from NSObject? Doesn't it automatically get called anyway once the custom object is initialized since it inherits from NSObject?  It just seems like more work on my behalf which isn't fair.  it should do it automatically.  Why wouldn't it do it automatically if it inherits from NSObject?
        super.init()
    }

    convenience init(random: Bool = false) {
        if random {
            let adjectives = ["Fluffy", "Rusty", "Shiny"]
            let nouns = ["MacBook Pro", "Red Tribe Bike", "Vegan Pizzas"]
            //take a variable that's random; the highest value for this random number will be the number of ojbects in the adjectives array
            var idx = arc4random_uniform(UInt32(adjectives.count))
            //now use this random variable and let it be the index of the adjectives array...so basically it'll be a random object from the adjectives array
            let randomAdjective = adjectives[Int(idx)]

            //AWESOME!! Now that the random adjective is stored in the randomAdjective constant, let's re-use the idx variable...Ayyyyeeeee re-use!

            //we'll re-use it by doing the same process or close to the same process for nouns
            idx = arc4random_uniform(UInt32(nouns.count))
            let randomNoun = nouns[Int(idx)]

            //now let's concatenate these two clever words, shall we!!
            let randomName = "\(randomAdjective) \(randomNoun)"

            //yayyy we're programmmminnngg!

            //now let's ....whad de fuk....
            let randomValue = Int(arc4random_uniform(100))
            let randomSerialNumber = NSUUID().uuidString.components(separatedBy: "-").first!

            let betterNotBeStolen: Bool = false

            self.init(name: randomName, valueInDollars: randomValue, serialNumber: randomSerialNumber, stolen: betterNotBeStolen)


        }
    }
}

Solution

  • You got the error

    "Cannot invoke 'Item.init' with an argument list of type '(name: String, valueInDollars: Int, serialNumber: String, stolen: Bool)'"

    because you missed the the dateCreated param in the self.init(params...).

    So you need to replace this line

    self.init(name: randomName, valueInDollars: randomValue, serialNumber: randomSerialNumber, stolen: betterNotBeStolen)
    

    with this one

    self.init(name: randomName, valueInDollars: randomValue, serialNumber: randomSerialNumber,dateCreated: NSDate(), stolen: betterNotBeStolen)
    

    The next error which you will see after is

    Self.init isn't called on all paths before returning from initializer

    So you need to add else statement because the initializer don't know what to do when the random param is false.

    convenience init(random: Bool = false) {
            if random {
                let adjectives = ["Fluffy", "Rusty", "Shiny"]
                let nouns = ["MacBook Pro", "Red Tribe Bike", "Vegan Pizzas"]
                //take a variable that's random; the highest value for this random number will be the number of ojbects in the adjectives array
                var idx = arc4random_uniform(UInt32(adjectives.count))
                //now use this random variable and let it be the index of the adjectives array...so basically it'll be a random object from the adjectives array
                let randomAdjective = adjectives[Int(idx)]
    
                //AWESOME!! Now that the random adjective is stored in the randomAdjective constant, let's re-use the idx variable...Ayyyyeeeee re-use!
    
                //we'll re-use it by doing the same process or close to the same process for nouns
                idx = arc4random_uniform(UInt32(nouns.count))
                let randomNoun = nouns[Int(idx)]
    
                //now let's concatenate these two clever words, shall we!!
                let randomName = "\(randomAdjective) \(randomNoun)"
    
                //yayyy we're programmmminnngg!
    
                //now let's ....whad de fuk....
                let randomValue = Int(arc4random_uniform(100))
                let randomSerialNumber = NSUUID().uuidString.components(separatedBy: "-").first!
    
                let betterNotBeStolen: Bool = false
    
                self.init(name: randomName, valueInDollars: randomValue, serialNumber: randomSerialNumber,dateCreated: NSDate(), stolen: betterNotBeStolen)
    
    
            } else {
    
               self.init(name: "SomeName", valueInDollars: 3, serialNumber: "123", dateCreated: NSDate(), stolen: true)
            }
        }