Select Multiple Items in SwiftUI List

Question

In UIKit you can select multiple rows of a UITableView by using allowsMultipleSelection - can this be done with the List in SwiftUI?

Answer 1

Here is an alternate way that uses a helper I created called Multiselect:

struct Fruit: Selectable {
    let name: String
    var isSelected: Bool
    var id: String { name }
}

struct FruitList: View {

    @State var fruits = [
        Fruit(name: "Apple", isSelected: true),
        Fruit(name: "Banana", isSelected: false),
        Fruit(name: "Kumquat", isSelected: true),
    ]

    var body: some View {
        VStack {
            Text("Number selected: \(fruits.filter { $0.isSelected }.count)")
            Multiselect(items: $fruits) { fruit in
                HStack {
                    Text(fruit.name)
                    Spacer()
                    if fruit.isSelected {
                        Image(systemName: "checkmark")
                    }
                }
            }
        }
    }
}

With the supporting code here:

protocol Selectable: Identifiable {
    var name: String { get }
    var isSelected: Bool { get set }
}

struct Multiselect: View {
    @Binding var items: [T]
    var rowBuilder: (T) -> V

    var body: some View {
        List(items) { item in
            Button(action: { self.items.toggleSelected(item) }) {
                self.rowBuilder(item)
            }
        }
    }
}

extension Array where Element: Selectable {
    mutating func toggleSelected(_ item: Element) {
        if let index = firstIndex(where: { $0.id == item.id }) {
            var mutable = item
            mutable.isSelected.toggle()
            self[index] = mutable
        }
    }
}