ItemsRepeater flicker

[dr1rrb]

Current behavior

No response

Expected behavior

No response

How to reproduce it (as minimally and precisely as possible)

No response

Workaround

No response

Works on UWP/WinUI

None

Environment

No response

NuGet package version(s)

No response

Affected platforms

No response

IDE

No response

IDE version

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Relevant plugins

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Anything else we need to know?

No response

[Youssef1313]

@dr1rrb Is this about ItemsRepeaterManyItems sample? Are you testing Gtk or WPF?

For Gtk, it's a known problem which I tried to fix, but the fix broke Gallery canary so it was reverted. See https://github.com/unoplatform/uno/pull/15811

[Youssef1313]

I can try another fix though

[dr1rrb]

@dr1rrb Is this about ItemsRepeaterManyItems sample? Are you testing Gtk or WPF?

For Gtk, it's a known problem which I tried to fix, but the fix broke Gallery canary so it was reverted. See #15811

Eh eh no it was only to have an issue to track my time ... but since I now found the root cause I can rename it and add details :)

[ramezgerges]

This needs a more detailed information. I tried this but no flickering happened:

// in sample constructor:
ir.DataContext = Enumerable.Range(0, 1000).Select(i => new VM(i.ToString(), i % 2 == 0)).ToList();


public class VM
{
    private string value;
    private bool isVisible;

    public VM(string value, bool isVisible)
    {
        this.value = value;
        this.isVisible = isVisible;
    }
    public string Value => value;
    public bool IsVisible => isVisible;
}

<ScrollViewer Height="400">
      <ItemsRepeater x:Name="ir" ItemsSource="{Binding}">
        <ItemsRepeater.ItemTemplate>
          <DataTemplate>
            <Border Visibility="{Binding IsVisible}">
              <TextBlock Text="{Binding Value}" />
            </Border>
          </DataTemplate>
        </ItemsRepeater.ItemTemplate>
      </ItemsRepeater>
    </ScrollViewer>

However, there is some extreme corruption happening. Reported in https://github.com/unoplatform/uno/issues/16992

[dr1rrb]

However, there is some extreme corruption happening. Reported in #16992

That's what I call "flicker" since it's when you scroll (depending of the scroll direction you will be able to see some items or not). Closing https://github.com/unoplatform/uno/issues/16992 as duplicate of this.

Edit: Feel free to rename this issue if you find it not descriptive enough ;)