ListBoxItem border is sometimes hidden behind the ListBox's scrollbar

Most of the time the ListBox appears like this:

But every once in a while it looks like this:

Any idea of what is going wrong?

开发者_开发百科--Edit--

I removed the control templates from the question, because when I removed them from my program the problem still existed. Is this a WPF bug?

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Have you tried setting SnapsToDevicePixels="True" on the ListBox Item border? Since the thickness is 1 "Device independent unit" I am thinking that the border is falling on a pixel boundry.

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I had almost the exact same problem, see my question, and I never found a real answer. What I do nowadays is strip the scrollviewer from the listbox template and embed the entire listbox itself in a new scrollviewer. Doesn't work for all occasions, but it's a neat trick nonetheless.

The xaml looks like this:

<ScrollViewer>

  <ListBox>

    <!--strip default presenter-->
    <ItemsControl.Template>
      <ControlTemplate>
        <ItemsPresenter />
      </ControlTemplate>
    </ItemsControl.Template>

    <ListBox.ItemTemplate>
      <DataTemplate>
        <!--data template goes here-->
      </DataTemplate>
    </ListBox.ItemTemplate>

  </ListBox>

</ScrollViewer>

I'm not a huge xaml wizard so if anybody could transfrom this into a reusable piece of code, by all means do so.