private void AuthorCountDecrement(NotifyCollectionChangedEventArgs e)
{
foreach (var removeBook in e.OldItems.Cast <BookViewModel>().Where(b => b.Author != null))
{
if (AuthorCount.Where(ac => ac.Author.Name == removeBook.Author.Name).Count() == 1)
{
var authorCount = AuthorCount.Single(ac => ac.Author.Name == removeBook.Author.Name);
authorCount.Count--;
}
}
}
private void AuthorCountInsertOrIncrement(NotifyCollectionChangedEventArgs e)
{
foreach (var newBook in e.NewItems.Cast <BookViewModel>().Where(b => b.Author != null))
{
if (AuthorCount.Where(ac => ac.Author.Name == newBook.Author.Name).Count() == 1)
{
var authorCount = AuthorCount.Single(ac => ac.Author.Name == newBook.Author.Name);
authorCount.Count++;
}
else if (AuthorCount.Where(ac => ac.Author.Name == newBook.Author.Name).Count() == 0)
{
AuthorCount.Add(new AuthorCountViewModel(newBook.Author, 1));
}
}
}