private void fetchTopics()
{
AllTopics = new ObservableCollection <Topic>();
AllTopics = new ObservableCollection <Topic>(dbh.GetAllTopics());
NotifyPropertyChanged("AllTopicGroups");
AllTopicGroups = new GroupedObservableCollection <string, Topic>(c => c.sectionId.ToString(), AllTopics.ToList());
NotifyPropertyChanged("AllTopicGroups");
}
public GroupedObservableCollection <TKey, TElement> ReplaceWith(GroupedObservableCollection <TKey, TElement> replacementCollection, IEqualityComparer <TElement> itemComparer)
{
// First make sure that the top level group containers match
var replacementKeys = replacementCollection.Keys.ToList();
var currentKeys = new HashSet <TKey>(this.Keys);
this.RemoveGroups(currentKeys.Except(replacementKeys));
this.EnsureGroupsExist(replacementKeys);
Debug.Assert(this.Keys.SequenceEqual(replacementCollection.Keys), "Expected this collection to have exactly the same keys in the same order at this point");
for (var i = 0; i < replacementCollection.Count; i++)
{
MergeGroup(this[i], replacementCollection[i], itemComparer);
}
return(this);
}