'Same ForEach loop twice in one SwiftUI View
When I use a ForEach loop over an array twice within a view, I get the following warning at runtime:LazyVGridLayout: the ID 84308994-9D16-48D2-975E-DC40C5F9EFFF is used by multiple child views, this will give undefined results!
The reason for this is clear so far, but what is the smartest way to work around this problem?
The following sample code illustrates the problem:
import SwiftUI
// MARK: - Model
class Data: ObservableObject
{
@Published var items: [Item] = [Item(), Item(), Item()]
}
struct Item: Identifiable
{
let id = UUID()
var name: String = ""
var description: String = ""
}
// MARK: - View
struct MainView: View {
@StateObject var data: Data
private var gridItems: [GridItem] { Array(repeating: GridItem(), count: data.items.count) }
var body: some View {
LazyVGrid(columns: gridItems, alignment: .leading, spacing: 2) {
ForEach(data.items) { item in
Text(item.name)
}
ForEach(data.items) { item in
Text(item.description)
}
}
}
}
// MARK: - App
@main
struct SwiftUI_TestApp: App {
var body: some Scene {
WindowGroup {
MainView(data: Data())
}
}
}
I could possibly divide the view into several SubViews.
Are there any other options?
Edit:
This is the body of the real app:
var body: some View {
VStack {
LazyVGrid(columns: columns, alignment: .leading, spacing: 2) {
Text("")
ForEach($runde.players) { $player in
PlayerHeader(player: $player)
}
ForEach(Score.Index.allCases) { index in
Text(index.localizedName)
ForEach(runde.players) { player in
Cell(player: player, active: player == runde.activePlayer, index: index)
}
}
Text ("")
ForEach(runde.players) { player in
PlaceView(player: player)
}
}
.padding()
}
}
Solution 1:[1]
If you really need that kind of grid filling, then it is possible just to use different identifiers for those ForEach
containers, like
LazyVGrid(columns: gridItems, alignment: .leading, spacing: 2) {
ForEach(data.items) { item in
Text(item.name).id("\(item.id)-1") // << here !!
}
ForEach(data.items) { item in
Text(item.description).id("\(item.id)-2") // << here !!
}
}
Tested with Xcode 13beta / iOS 15
Solution 2:[2]
While adding identifiers within the ForEach loop sometimes works, I found that accessing the indexes from the loop with indices worked in other cases:
ForEach(items.indices, id: \.self) { i in
Text(items[i])
}
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
Solution | Source |
---|---|
Solution 1 | |
Solution 2 | codingCartooningCPA |