SOLVED: Trouble with creating a loop that increments a value.

@Jawds

Oct '20

Hi,

I am making an app that stores a user's food items throughout the day, as well as letting them enter the calories for each specific food item.

I am using a ForEach to add them all to a singular var which will then be displayed in the user interface.

Let me know if any context for the code is needed.

var calorieAmount: Int {
        let calendar = Calendar.current
        let day = calendar.component(.day, from: entrydate)
        var calorieTotal = 0

        ForEach(foods, id: \.self) { food in
            if (food.date == day) {
                var calories: Int = Int(food.calories)
                calorieTotal += calories
            }
        }
        return calorieTotal
    }

This returns an error within ContentView (Type '()' cannot conform to 'View'; only struct/enum/class types can conform to protocols).

I don't know whether this is due to me placing it in the wrong place, or just has to do with the structure of the code itself.

Thank you in advance.

@roosterboy HWS+

Oct '20

I assume this is inside the body property of a View? Yeah, you can't do that. Instead, you need to do something like this:

var calorieAmount: Int {
    let calendar = Calendar.current
    let day = calendar.component(.day, from: entrydate)
    var calorieTotal = 0

    for food in foods {
        if food.date == day {
            calorieTotal += food.calories
        }
    }

    return calorieTotal
}

Since this is not part of the body, you can't use ForEach and have to use a regular for loop.

This needs to be a computed variable in your ContentView struct but outside of the body property. So...

struct ContentView: View {
   let foods: [Food]

   var calorieAmount: Int {
       //... above code
   }

   var body: some View {
       //...your UI content, where at some poiunt you reference calorieAmount
   }
}

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