public void AddGroupCategory(Category category)
{
var idx = DbAllCategories.IndexOf(category);
var insertionPoint = DbGroupCategories.FirstIndex(
item => DbAllCategories.IndexOf(item) > idx);
if (insertionPoint == null)
{
DbGroupCategories.Add(category);
}
else
{
DbGroupCategories.Insert((int)insertionPoint, category);
}
}
private void AllCategoriesCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
Category cat;
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
if (e.NewItems == null)
{
return;
}
cat = ((CategoryWrapper)e.NewItems[0]).Category;
DbAllCategories.Insert(e.NewStartingIndex, cat);
if (_reinsert)
{
AddGroupCategory(cat);
}
_reinsert = false;
break;
case NotifyCollectionChangedAction.Remove:
if (e.OldItems == null)
{
return;
}
var catWrap = ((CategoryWrapper)e.OldItems[0]);
cat = ((CategoryWrapper)e.OldItems[0]).Category;
DbAllCategories.RemoveAt(e.OldStartingIndex);
if (catWrap.IsGrouping)
{
_reinsert = true;
DbGroupCategories.Remove(cat);
}
break;
}
}
