private void DownStyleChange(Label label)
{
if (label == null)
{
CollectionStack.SelectItem = CollectionSource.First();
}
else
{
int index = CollectionSource.ToList().IndexOf(label);
if (index != CollectionSource.Count() - 1)
{
int offset = GetScrollViewerOffset();
if (offset + 9 == index)
{
SetScrollViewerOffset(offset + 1);
}
else if (offset > index || offset + 9 < index)
{
SetScrollViewerOffset(index + 1);
}
StyleChange(label);
CollectionStack.SelectItem = CollectionSource.ElementAt(index + 1);
}
}
}
private void UpStyleChange(Label label)
{
if (label != null)
{
int index = CollectionSource.ToList().IndexOf(label);
if (index != 0)
{
int offset = GetScrollViewerOffset();
if (offset == index)
{
SetScrollViewerOffset(offset - 1);
}
else if (offset > index || offset + 9 < index)
{
SetScrollViewerOffset(index - 1);
}
StyleChange(label);
CollectionStack.SelectItem = CollectionSource.ElementAt(index - 1);
}
}
}
