public class MyInfo
{
  public int ID { get; set; }
  public string Remark { get; set; }
  public IsChecked { get; set; }
}

(ObservableCollection<MyInfo>)e.NewItems

Data.ForEach(x => x.ProperyChanged += MyPropertyChanged)

private void SetHandler(ObservableCollection<MyInfo> data)
{
  data.ForEach(x => x.ProperyChanged += MyPropertyChanged);
}

SetHandler((ObservableCollection<MyInfo>)e.NewItems); // error

private bool _isCheckedLV;
public bool IsCheckedLV
{
  get { return _isCheckedLV; }
  set { _isCheckedLV= value; OnPropertyChanged(); }
}

public MyViewModel()
{
  <...>
  SetHandlerToEventIsCheckedChanged(Data);
  Data.CollectionChanged += Data_CollectionChanged;
}

private void SetHandlerToEventIsCheckedChanged(IEnumerable<MyInfo> data)
{
  data.ForEach(x => x.PropertyChanged += InfoPropertyChanged);
}

private void Data_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
  SetHandlerToEventIsCheckedChanged(e.NewItems.Cast<MyInfo>());
  SetChecked();
}

private void InfoPropertyChanged(object sender, PropertyChangedEventArgs e)
{
  if (e.PropertyName == "IsChecked")
  {
    SetChecked(); 
  } 
}

private void SetChecked()
{
  IsCheckedLV = Data.Any(x => x.IsChecked);
}