Hi!

This simple app should scroll to the last line of a list after appending a new item. The code works fine with iOS 15 but cause a runtime error on iOS 16.

import SwiftUI

struct ScrollListView: View {
    @State private var data: [String] = []

    var body: some View {
        VStack {
            Button(action: {
                data.append("ScrollItem #\(data.count+1)")
            }) {
                Label("Add Row", systemImage: "plus")
            }
            .buttonStyle(.borderedProminent)

            ScrollViewReader { proxy in
                List(0..<data.count, id: \.self) { index in
                    Text(data[index]).id(index)
                }
                .listStyle(.grouped)
                .navigationTitle("ScrollList Test")
                .onChange(of: data.count) { _ in
                    proxy.scrollTo(data.count-1)
                }
            }
        }
        .onAppear() {
            for _ in 0..<30 {
                data.append("ScrollItem #\(data.count+1)")
            }
        }
    }
}

The error occures on line: proxy.scrollTo(data.count-1):

0x0000000100fb8050 in closure #2 in closure #3 in closure #1 in ScrollListView.body.getter at /…/TestApp/Features/Scrollview/ScrollTestView.swift:29

Does anyone have an idea or a workaround for iOS 16?

A workaround for this bug is to add a UUID id to the List. It causes it to be recreated every time data updates, but the scrolling works properly.

  List(0..<data.count, id: \.self) { index in
      Text(data[index]).id(index)
  }
  .id(UUID())
 ...

Great workaround, I don't suppose there's anyway to keep the animation? Mine just jumps to the top.

I have been struggling with this. Thanks.

However I think I am missing something. I have a List - ForEach and don't seem to make the scrollTo work (but no crashes at least. Any ideas on where I am going wrong in this code?

ScrollViewReader { proxy in
                        List {
                            ForEach(scoredSkippers, id: \.self) { skip in
                                HStack {
                                    VStack {
                                        Image(systemName: "\(Int(skip.raceRawScore)).circle.fill")
                                        Text(skip.raceLetterScore == .👍 ? "" : " \(skip.raceLetterScore.rawValue)").font(.caption2)
                                    }
                                    Spacer()
                                    Text(String(skip.sailNum))
                                    Spacer()
                                }
                                .onLongPressGesture {
                                    isShowingRaceScore = skip
                                }
                                .listRowBackground(skip.raceLetterScore != .👍 ? Color(.systemYellow) : nil)

                            }
                            .onMove(perform: move)
                        }
                        .id(UUID())
                        .scrollContentBackground(.hidden)
                        .background(.green.opacity(0.05))
                        .sheet(item: $isShowingRaceScore) { skip in
                            UpdateScoreView(thisRscore: skip)
                            }
                        .environment(\.editMode, .constant(.active))
                        .onChange(of: scoredSkippers.count) { _ in
                            proxy.scrollTo(scoredSkippers.count - 1)
                            }
                    }