private void OnItemAppearing(object sender, ItemVisibilityEventArgs eventArgs)
{
var message = eventArgs.Item as MessageViewModel;
var index = _chatStream.Messages.IndexOf(message);
if (index == 0 && _didScrollToEnd && !_chatStream.IsLoading)
{
_chatStream.Load();
}
if (index == _chatStream.Messages.Count() - 1)
{
_didScrollToEnd = true;
}
}
protected override void OnAppearing()
{
base.OnAppearing();
_viewModel.Load();
}