A wrapper collection that provides items with its index using underlying collection without allocation.
In SwiftUI, we might use these following technique for using index in ForEach.
ForEach(Array(array.enumerated()), id: \.offset) { ... }ForEach(zip(array.indices, array), id: \.0) { ... } There is downside like followings:
- Creating new buffer by making new collection
enumeratedprovides index from 0 so that makes wrong access on using slice.
#Preview {
VStack {
ForEach.init(IndexedCollection([1, 2, 3, 4, 5]), id: \.index, content: { e in
Text("\(e.index): \(e.value)")
})
}
}struct IdentifiableItem: Identifiable {
let id: String
let value: UUID = .init()
}
#Preview {
VStack {
ForEach.init(IndexedCollection(["a", "b", "c", "d", "e"].map(IdentifiableItem.init(id:))), content: { e in
Text("\(e.index): \(e.value)")
})
}
}