Reputation: 179
I am confused as to how to retrieve the item 'cal' in the row which is deleted on 'onDelete'. using that to generate a total entry. trying to get 'diary.items[offsets].cal'. hopefully I am explaining this.
the code below generates a list of four entries when '+' sign is hit and provides a total field on the top line. my purpose is to decrement the top line accordingly when a row is deleted
import SwiftUI
struct Entry: Identifiable {
let id = UUID()
let food : String /* changing item to food */
let cal : String
}
class Diary: ObservableObject {
@Published var items = [Entry]()
}
struct ContentView: View {
@ObservedObject var diary = Diary()
@State var fooditem = ""
@State var calories = ""
@State var totcals = 0
var body: some View {
Form {
Button(action: {
var entry = Entry(food: fooditem, cal: calories)
let count = 1...4
for number in count {
entry = Entry(food: String(number), cal: String(number*2))
self.diary.items.append(entry)
totcals += number*2
}
}) { Image(systemName: "plus") }
VStack{
Text(" totals = " + String(totcals))
}
List {
ForEach(diary.items, id:\.food) { item in
Text(item.food + ": " + item.cal + " cals")
}.onDelete(perform: removeItems)
}
}
}
func removeItems( at offsets: IndexSet) {
diary.items.remove(atOffsets: offsets)
// need a way find cals associated with this offset in order
// to subtract it from total onDelete
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView( )
}
}
Upvotes: 2
Views: 974
Reputation: 36304
try this:
func removeItems(at offsets: IndexSet) {
for i in offsets.makeIterator() {
let theItem = diary.items[i]
// theItem.cal
// do something with theItem.cal
}
diary.items.remove(atOffsets: offsets)
}
Upvotes: 3