private void OnPagesChanged(object sender, NotifyCollectionChangedEventArgs e)
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
int index = e.NewStartingIndex;
for (int i = 0; i < e.NewItems.Count; i++)
{
var page = e.NewItems[i] as Page;
Widget.AddPage(index, page);
_pages.Add(new PageContainer(page, i));
index++;
}
var newPages = new List <object>();
foreach (var pc in _pages)
{
newPages.Add(pc.Page);
}
e.Apply(Page.Children, newPages);
break;
case NotifyCollectionChangedAction.Remove:
for (int i = 0; i < e.OldItems.Count; i++)
{
var page = e.OldItems[i];
Widget.RemovePage(page);
var pageContainer = _pages.FirstOrDefault(p => p.Page == page);
_pages.Remove(pageContainer);
}
var oldPages = new List <object>();
foreach (var pc in _pages)
{
oldPages.Add(pc.Page);
}
e.Apply(Page.Children, oldPages);
UpdateCurrentPage();
break;
case NotifyCollectionChangedAction.Reset:
Widget?.Reset();
UpdateSource();
break;
}
}