[Desktop] ItemsWrapGrid does not work in ListView.ItemsPanel when used as ItemsPanelTemplate

[kucint]

Current behavior

define user control with following content:

<UserControl.Resources>
  <CollectionViewSource x:Name="CategoryCollectionViewSource" IsSourceGrouped="True" />
</UserControl.Resources>

<ListView ItemsSource="{x:Bind CategoryCollectionViewSource.View, Mode=OneWay}"
          SelectionMode="Single"
          ShowsScrollingPlaceholders="True"
          BorderThickness="{ThemeResource ListBoxBorderThemeThickness}"
          BorderBrush="{ThemeResource ListBoxBorderThemeBrush}"
          SelectedItem="{x:Bind SelectedItem, Mode=TwoWay}">

  <ListView.ItemsPanel>
    <ItemsPanelTemplate>
      <!--If the following line (<ItemsWrapGrid/>) will be commented out
      and the PRJ will be launched in net9.0-desktop mode,
      5 Items (A, B, C, D, E), will be displayed in a ListView.
      However, if the following line is active, nothing will be displayed.

      Note: In net9.0-windows it works as expected with and without that line.

      Our fazit: ItemsWrapGrid is not compatible with net9.0-desktop.-->

      <ItemsWrapGrid/>

    </ItemsPanelTemplate>
  </ListView.ItemsPanel>

  <ListView.ItemContainerStyle>
    <Style TargetType="ListViewItem" BasedOn="{StaticResource DefaultListViewItemStyle}">
      <Setter Property="MinWidth" Value="0"/>
      <Setter Property="Margin" Value="0,0"/>
      <Setter Property="Padding" Value="15,0,15,0"/>
    </Style>
  </ListView.ItemContainerStyle>

  <ListView.ItemTemplate>
    <DataTemplate x:DataType="local:Item">
      <TextBlock Text="{x:Bind Label}" HorizontalAlignment="Center"/>
    </DataTemplate>
  </ListView.ItemTemplate>

</ListView>

and use it in a Page:

<Grid>

    <acc:AccordionCtrl x:Name="AccordionCtrl"
                     Grid.Column="0" Grid.Row="0"
                     Margin="5"
                     HorizontalAlignment="Stretch"
                     VerticalAlignment="Stretch"/>

</Grid>

Expected behavior

this works correctly on WindowsAppSdk:

but fails on Desktop:

Apparently ItemsWrapGrid fails to display its content when used as a template in ListView.ItemsPanel

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

MINIMAL REPRO PROJECT: MWEApp.zip

Workaround

none

Works on UWP/WinUI

Yes

Environment

No response

NuGet package version(s)

No response

Affected platforms

Skia (WPF)

IDE

Visual Studio 2022

IDE version

No response

Relevant plugins

"Uno.Sdk": "5.5.54"

Anything else we need to know?

No response

[jeromelaban]

Thanks the report. This is indeed currently not yet supported for desktop #4023. Using ItemsRepeater can be another way to implement this.

[DevTKSS]

@jeromelaban can you tell the reason for it to not work or is it only the itemswrapgrid control which is just not jet available?

[MichaelJachan]

Dear Jerome! I am the coworker of Tomasz.

1. In Desktop, the Control ItemsWrapGrid is "available", i.e., it compiles. But at runtime, it does not display. I guess, there is no implementation for it.

2. What is your proposal of a workaround?

Best, Michael :)

[jeromelaban]

1. In Desktop, the Control ItemsWrapGrid is "available", i.e., it compiles. But at runtime, it does not display. I guess, there is no implementation for it.

Indeed, it's not implemented at this time.

What is your proposal of a workaround?

You can use the ItemsRepeater control and custom layouts to implement a wrap grid, such as the WrapLayout.

[MichaelJachan]

Good Morning! You said, ItemsWrapGrid is already implemented (also in Desktop)? When can we expect a bugfix?

Best, Michael

[jeromelaban]

My apologies, my answer missed a not.

It's not a bug in this case, it's a missing feature. At this time this has not been prioritized by our clients and we do not have a timeline for an implementation.

[MichaelJachan]

OK. Then, I would urgently need a workaround, which replaces the ItemsWrapGrid, in order to implement an AccordionControl based on a ListView please:)

[MichaelJachan]

@jeromelaban:

... for your overview, I have here collected the nature of the workaround using ItemsRepeader. The problem seems for me newbie to be with the ItemsSource for the ItemsRepeater.

First, I succeeded to use the ItemsRepeater as the Main Content of MySandboxControl:

    <ItemsRepeater ItemsSource="{x:Bind MyItems}">
      <ItemsRepeater.Layout>
        <UniformGridLayout Orientation="Horizontal" MinItemWidth="52"/>
      </ItemsRepeater.Layout>
    </ItemsRepeater>

And it does what is expected: 10 strings (MyItems) are displayed and wrapped according to the width of the window.

BUT SECOND, my actual case is more involved. The original ItemsWrapGrid is used within a ListView-ItemsPanelTemplate like that:

      <ListView.ItemsPanel>
        <ItemsPanelTemplate>

          <ItemsWrapGrid Orientation="Horizontal" GroupPadding="0,0" GroupHeaderPlacement="Top" AreStickyGroupHeadersEnabled="True"/>

        </ItemsPanelTemplate>
      </ListView.ItemsPanel>

THUS, I guess, I need to use the new ItemsRepeater like:

      <ListView.ItemsPanel>
        <ItemsPanelTemplate>

          <ItemsRepeater>
            <ItemsRepeater.Layout>
              <UniformGridLayout Orientation="Horizontal" MinItemWidth="52"/>
            </ItemsRepeater.Layout>
          </ItemsRepeater>

        </ItemsPanelTemplate>
      </ListView.ItemsPanel>

BUT I did not succeed to set an ItemsSource for the ItemsRepeater.

[jeromelaban]

Thanks for the update. It's best if you open a discussion with your sample code, as it's not related to the ItemsWrapGrid issue.