Cannot invoke 'indexOf' with an argument list of type '(ChecklistItem)'

Question

When I am writing code for finding an item from the array with the use of indexOf it shows me the above stated error. Here is my code:-

func addItemViewContr         


        

Answer 1

indexOf can only be applied to Collections of Equatable types, your ChecklistItem doesn't conform to Equatable protocol (have an == operator).

To be able to use indexOf add this to the file containing ChecklistItem class in the global scope :

func ==(lhs: ChecklistItem, rhs: ChecklistItem) -> Bool {
    return lhs === rhs
}

Swift3: 
public static func ==(lhs: Place, rhs: Place) -> Bool {
        return lhs === rhs
    }

Please note it will make comparison by comparing instances addresses in memory. You may want to check equality by comparing members of the class instead.