Hello,
Welcome to our Microsoft Q&A platform!
As you said, you need to set the upper limit of the loop to avoid the SelectedIndex exceeding its maximum number. So You can try to use BigPivot.Items.Count property to set.
private int index = 0;
private void dispatcherTimer_Tick(object sender, object e)
{
index++;
if (index < BigPivot.Items.Count)
{
BigPivot.SelectedIndex++;
}
else {
// do something
}
}
Thanks.