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iOS

ali aboutaleb
ali aboutaleb
4,025 Points
Posted by ali aboutaleb
ali aboutaleb
4,025 Points

Cant fix the mistake that passan made! CAN ANYONE HELP??

I guess that i need to type cast something because the error i have is " Cannot convert value of type 'UILabel!' to expected argument type 'Double?'"

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

        quantityStepper.value = 1
       updateDisplaywith(totalPrice: 0, itemQuantity: 1)


        totalLabel.text = "00.00"

        updateDisplaywith(totalPrice: 0,  itemQuantity: 1)

        currentSelection = vendingMachine.selection[indexPath.row]

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


            let totalPrice = item.price * quantityStepper.value

            updateDisplaywith( totalPrice: totalLabel, itemPrice: item.price)

        }
    }
Steve Hunter
Steve Hunter
57,712 Points

I'm guessing the error is at the updateDisplayWith method. You're passing in totalLabel which is of type UILabel but the method is expected a numerical value of type Double. Can you convert the totalLabel.text value to a Double? It holds a numeric value represented as a String.

Without a link to the video, I can't see what's shown.

Steve.

ali aboutaleb
ali aboutaleb
4,025 Points
ali aboutaleb
ali aboutaleb
4,025 Points

Thank you steve for responding, i tried what you said and i changed the totalLabel.text to double but it also gave me an error that said "Cannot assign value of type 'Double.Type' to type 'String?'"

1 Answer

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi again,

If you pause the video at 17m26s, you can see that your method isn't quite the same as in the video. I don't know if the rest of your code mirrors the video as I can't see it all.

However, the last line: 

updateDisplaywith( totalPrice: totalLabel, itemPrice: item.price)

in the video is:

updateDisplaywith( totalPrice: totalPrice, itemPrice: item.price)

You've defined the totalPrice constant above this line, so that's fine. So, making that change stops you passing a UILabel to the method that's expecting a Double.

I hope that helps,

Steve.