Flutter: Performance by creating a big List when Widget gets build

Question

I want to build a List of data which gets created when the Widget build. My Question is, how good is the performance when the list is big (ListLength ~= 1000)? Will there be performance issues by building the Widget or is this solution good?

Here an example whats the idea is:

  List<Map<String, Object>> get listWithValues {
    return List.generate(myListLength, (index) {
      return  {'value': index, 'date': DateTime.now()};
    });
  }

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
                itemCount: listWithValues.length,
                itemBuilder: (context, i) {
                     return ListTile(
                        title: Text(listWithValues[i]['value'].toString()),