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copied!<p>All you need to do is to get the underlying StackPanel that's inside the ListBox. It has enough information about which elements are showing. (It implements the interface IScrollInfo).</p> <p>To get the underlying StackPanel (or actually VirtualizingStackPanel) from a given ListBox, we'll have to use VisualTreeHelper to go through the Visual Tree and look for the VirtualizingStackPanel, like so:</p> <pre><code> private VirtualizingStackPanel GetInnerStackPanel(FrameworkElement element) { for (int i = 0; i < VisualTreeHelper.GetChildrenCount(element); i++) { var child = VisualTreeHelper.GetChild(element, i) as FrameworkElement; if (child == null) continue; Debug.WriteLine(child.ToString()); if (child is VirtualizingStackPanel) return child as VirtualizingStackPanel; var panel = GetInnerStackPanel(child); if (panel != null) return panel; } return null; } </code></pre> <p>Now that we have the StackPanel, we're very close. The StackPanel has the properties <code>VerticalOffset</code> and <code>ViewportHeight</code> (both coming from <code>IScrollInfo</code>) that can give us all the information we need.</p> <pre><code> private void button1_Click(object sender, RoutedEventArgs e) { var theStackPanel = GetInnerStackPanel(MyListBox); List<FrameworkElement> visibleElements = new List<FrameworkElement>(); for (int i = 0; i < theStackPanel.Children.Count; i++) { if (i >= theStackPanel.VerticalOffset && i <= theStackPanel.VerticalOffset + theStackPanel.ViewportHeight) { visibleElements.Add(theStackPanel.Children[i] as FrameworkElement); } } MessageBox.Show(visibleElements.Count.ToString()); MessageBox.Show(theStackPanel.VerticalOffset.ToString()); MessageBox.Show((theStackPanel.VerticalOffset + theStackPanel.ViewportHeight).ToString()); } </code></pre>

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