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iOS Build a Vending Machine App in Swift Using the Vending Machine Updating the Price

get error of optional type VendingSelection?

here is part of my code, and error shows: Value of optional type 'VendingSelection?' not unwrapped; did you mean to use '!' or '?'?

// MARK: - UICollectionViewDelegate

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    updateCell(having: indexPath, selected: true)

    currentSelection = vendingMachine.selection[indexPath.row]

    if let currntselection = currentSelection, let item = vendingMachine.irem(forSelection: currentSelection) {

        priceLabel.text = "$\(item.price)"
        totalLabel.text = "$\(item.price * Double(quantity))"

my code looks like the same as tutor's. I don't know where I did wrong..

1 Answer

Ignazio Calo
Ignazio Calo
Courses Plus Student 1,819 Points

look at your line:

if let currntselection = currentSelection, let item = vendingMachine.irem(forSelection: currentSelection) { }

which object are you using inside the vendingMachine.irem(forSelection: currentSelection) ?

There is a typo on the first variable definition, therefore you're still using the global optional currentSelection object.

I really suggest to use different names inside the if let <something> = <something>.

Gavin Hobbs
Gavin Hobbs
5,205 Points

Hey Ignazio Calo we would use different names for if let <something> = <something>; however, those are the names Pasan used. I totally understand your reasoning though.