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Changing the opacity in the long list allows you to delete the last elements

I created a list with the Opacity option, whose value is less than 1, and when I anchor a long list, the last elements disappear.

I created a small sample to reproduce the problem.

In the XAML list:

<ListBox x:Name="mainList" ItemsSource="{Binding}" Opacity="0.5"></ListBox>

and it is tied to a long list:

   public MainPage()
    {
        InitializeComponent();
        List<int> l = new List<int>();
        for (int i = 0; i < 100; i++)
        {
            l.Add(i);
        }

        this.DataContext = l;
    }

When I execute it, the last element that I see is “87”, there is a place for the rest of the elements below, but it is completely black.

What is the problem?

edit: a colleague told me that this is probably a virtualization problem, since the problem occurs on 87 and there are 29 elements on the screen (the list virtualizes 3 times the number of displayed elements, 3 * 29 = 87). I did the same test with ItemsControl (without virtualization) and the problem is the same.

+3
1

* - - , , , ListBox 1, DataTemplate 0.5.

:

        <ListBox x:Name="mainList" ItemsSource="{Binding}" Opacity="1">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <TextBlock Opacity="0.5" Text="{Binding}">

                    </TextBlock>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
+1

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