public static IDisposable connect_item_actions <T>(INotifyCollectionChanged notifier, IEnumerable <T> collection, Action <T> action)
{
foreach (T v in collection)
{
action(v);
}
return(notifier.Subscribe((s, e) => CollectionHelper.process_new_items(collection, action, e)));
}
public static IDisposable connect_set <T>(IList <T> source_list, INotifyCollectionChanged source_notifier, ISet <T> target)
{
return(source_notifier.Subscribe(callback));
void callback(object sender, NotifyCollectionChangedEventArgs e)
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
foreach (T v in e.NewItems)
{
target.Add(v);
}
break;
case NotifyCollectionChangedAction.Remove:
foreach (T v in e.OldItems)
{
target.Remove(v);
}
break;
case NotifyCollectionChangedAction.Replace:
foreach (T v in e.OldItems)
{
target.Remove(v);
}
foreach (T v in e.NewItems)
{
target.Add(v);
}
break;
case NotifyCollectionChangedAction.Reset:
target.Clear();
for (int i = 0; i < source_list.Count; i++)
{
target.Add(source_list[i]);
}
break;
}
}
}
public static IDisposable connect_sorted_distinct_mux <T, TResult>(IList <T> source_list, INotifyCollectionChanged source_notifier, IList <TResult> target, Func <T, IEnumerable <TResult> > selector, IComparer <TResult> comparer, IEqualityComparer <TResult> eq_comparer)
{
var ref_count = new RefCountMap <TResult>(eq_comparer);
if (target.Count > 0)
{
target.Clear();
}
foreach (var v in source_list)
{
var r = selector(v);
target.InsertSortedDistinct(r, comparer);
}
return(source_notifier.Subscribe(on_collection_changed));
void on_collection_changed(object sender, NotifyCollectionChangedEventArgs e)
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
target.InsertSorted(e.NewItems.Cast <T>().SelectMany(selector).Where(ref_count.increment_adds_key), comparer);
break;
case NotifyCollectionChangedAction.Remove:
target.RemoveSorted(e.OldItems.Cast <T>().SelectMany(selector).Where(ref_count.decrement_removes_key), comparer);
break;
case NotifyCollectionChangedAction.Replace:
target.RemoveSorted(e.OldItems.Cast <T>().SelectMany(selector).Where(ref_count.decrement_removes_key), comparer);
target.InsertSorted(e.NewItems.Cast <T>().SelectMany(selector).Where(ref_count.increment_adds_key), comparer);
break;
case NotifyCollectionChangedAction.Reset:
target.Clear();
ref_count.Clear();
target.InsertSorted(source_list.SelectMany(selector).Where(ref_count.increment_adds_key), comparer);
break;
}
}
}
public static IDisposable Subscribe(this INotifyCollectionChanged collection, Action callback)
{
return(collection.Subscribe(_ => callback()));
}
