Xamarin forms iOS CollectionView steals focus after ItemsSource property is changed - xamarin.forms

Question

I have a page with a collection view and a search bar that filters its contents.
I want the filtering to happen as the user types in the search bar, so I bind the TextChanged event of the SearchBar to a command in the view model, like so
var eventToCommandBehavior = new EventToCommandBehavior()
{
EventName = nameof(searchBar.TextChanged),
};
eventToCommandBehavior.SetBinding(EventToCommandBehavior.CommandProperty, nameof(MyViewModel.StartOrResetSearchTimerCommand));
searchBar.Behaviors.Add(eventToCommandBehavior);
In the view model:
public ICommand StartOrResetSearchTimerCommand => new Command(() =>
{
StartOrResetSearchTimer();
});
private void StartOrResetSearchTimer()
{
if (!timerStarted)
{
searchTimer = new Timer(_ => PerformSearch(), null, searchTimeout, searchTimeout);
timerStarted = true;
}
else
ResetTimer();
}
private void PerformSearch()
{
//my code
OnPropertyChanged(collectionViewItemsSourceBinding);
}
The StartOrResetSearchTimerCommand filters the ItemsSource binding, and calls OnPropertyChanged(itemsSourceBinding) to update the UI.
On Android and UWP everything works as expected. However on iOS, when OnPropertyChanged is called, the focus moves out of the search bar, resulting to the soft keyboard being closed after each keyboard input.
Has anyone else encountered this? Any suggestions?
I have already tried not using this approach, and only filter the ItemsSource when the search button is pressed, which works, when there is something to search for (ie, there is some input in the search bar)
When the search bar text is empty (ie after Backspace) then the search button is greyed out.
Update
For now, I am using this workaround:
Perfom the search only when the search button is pressed, and on TextChanged, check if the text is empty and reset the ItemsSourceworka

Answer 1

TextChanged is called anytime the text in the query box is changed. You can use this event to update your ItemsSource when the Text of the searchbar changes. You can refer to this part of the official example. First, given your ItemsSource, when you enter text in the searchbar, call the OnTextChanged event to update your ItemsSource, so that the real-time search keyboard will not lose focus.