async private void loadCategories()
{
menuCategories = await fb.ListMenuCategoriesName(parent.restaurantName);
customerCheckedListBox.Items.Clear();
foreach (var item in menuCategories)
{
customerCheckedListBox.Items.Add(item);
}
for (int i = 0; i < customerCheckedListBox.Items.Count; i++)
{
if (parent.filterCategories.Contains(customerCheckedListBox.Items[i].ToString()))
{
customerCheckedListBox.SetItemChecked(i, true);
}
}
}