How get visual items of a ComboBox using databinding?

Question

It's a followup question of https://learn.microsoft.com/en-us/answers/questions/1656636/how-do-i-know-when-a-binding-is-complete.

The ComboBox is databound using ItemsSource, now I don't have control of the Items property because it's a simply set to what ItemsSource is.

I need to enumerate over the generated visual items, how do I get them?

I tried the following code, but did not get what I expected.

var root = VisualTreeHelper.GetChild(combo1, 0);
var cc = VisualTreeHelper.GetChildrenCount(root);
for (int i = 0; i < cc; i++)
{
    var child = VisualTreeHelper.GetChild(root, i);
    if (child is FrameworkElement elem)
        Debug.WriteLine(elem.Name);
}

Answer 1

Oh my... At last, I found the answer myself.

for (var i = 0; i < myListView.Items.Count; i++)
{
    var lvi = (ListVieItem)myListView.ContainerFromIndex(i);
}

But I am still stuck at this problem: https://learn.microsoft.com/en-us/answers/questions/1656636/how-do-i-know-when-a-binding-is-complete.