private void ScrollToLetter(string letter)
{
if (TargetControl == null || TargetControl.ItemsSource == null)
{
return;
}
var collectionView = CollectionViewSource.GetDefaultView(TargetControl.ItemsSource);
if (collectionView == null)
{
throw new InvalidOperationException("The TargetControl should use ICollectionView as ItemSource.");
}
if (string.IsNullOrEmpty(TargetPropertyPath))
{
throw new InvalidOperationException("TargetPropertyPath is not set.");
}
var firstWithLetter = collectionView.SourceCollection.Cast <object>().FirstOrDefault(o => o.DynamicAccess <string>(TargetPropertyPath)?.StartsWith(letter, true, CultureInfo.InvariantCulture) ?? false);
if (firstWithLetter != null)
{
var scrollViewer = TargetControl.FindChild <ScrollViewer>();
scrollViewer.ScrollToBottom();
TargetControl.ScrollIntoView(firstWithLetter);
}
}
private void ScrollToMonth(int month)
{
if (TargetControl == null || TargetControl.ItemsSource == null)
{
return;
}
var collectionView = CollectionViewSource.GetDefaultView(TargetControl.ItemsSource);
if (collectionView == null)
{
throw new InvalidOperationException("The TargetControl should use ICollectionView as ItemSource.");
}
if (string.IsNullOrEmpty(TargetPropertyPath))
{
throw new InvalidOperationException("TargetPropertyPath is not set.");
}
var firstAtMonth = collectionView.SourceCollection.Cast <object>().FirstOrDefault(o => o.DynamicAccess <DateTime?>(TargetPropertyPath)?.Month.Equals(month) ?? false);
if (firstAtMonth != null)
{
var scrollViewer = TargetControl.FindChild <ScrollViewer>();
scrollViewer.ScrollToBottom();
TargetControl.ScrollIntoView(firstAtMonth);
}
}