[Bug] Setting CarouselView position in C# doesn't always change the CurrentItem visually on UWP

[CMarcher]

Description

When I try to change the position of a CarouselView on UWP in the code-behind, some very odd behaviour occurs. If I click the button tied to an event handler that sets the position differently, the CarouselView jitters but does not change. If I click three or four times in quick succession, it changes. Sometimes it decides to change immediately, other times it doesn't.

Steps to Reproduce

1. Create new Xamarin Forms solution with only UWP selected for the blank template.
2. Update all NuGet packages for solution to latest versions.
3. Copy this XAML code into your MainPage content, replacing what the template puts there:

<StackLayout>
        <Grid ColumnDefinitions="*, *" ColumnSpacing="20"
              Margin="10">

            <Button Text="Panel 1" x:Name="panelOneButton"
                    Clicked="panelOneButton_Clicked" Grid.Column="0"/>

            <Button Text="Panel 2" x:Name="panelTwoButton"
                    Clicked="panelTwoButton_Clicked" Grid.Column="1"/>
        </Grid>

        <CarouselView VerticalOptions="FillAndExpand" x:Name="carouselView"
                      BackgroundColor="Gray">
            <CarouselView.ItemsSource>

                <x:Array Type="{x:Type x:String}">
                    <x:String>Baboon</x:String>
                    <x:String>Capuchin Monkey</x:String>
                </x:Array>
            </CarouselView.ItemsSource>

            <CarouselView.ItemTemplate>
                <DataTemplate>
                    <Label Text="{Binding .}"/>
                </DataTemplate>
            </CarouselView.ItemTemplate>
        </CarouselView>
    </StackLayout>

4. Copy this C# code into MainPage.xaml.cs:

private void panelTwoButton_Clicked(object sender, EventArgs e)
{
    carouselView.Position = 1;
}

private void panelOneButton_Clicked(object sender, EventArgs e)
{
    carouselView.Position = 0;
}

5. Build and run the solution in UWP, click the buttons and see.

Expected Behavior

Clicking a button that is set to change the CarouselView's current position will change the current item visually.

Actual Behavior

Clicking a button that is set to change the CarouselView's current position will jitter sometimes, possibly decide to change to the corresponding item or not.

Basic Information

• Version with issue: 5.0.0.1931
• Last known good version:
• Platform Target Frameworks:
  • UWP: 6.2.11
• NuGet Packages: The base packages installed when you use the Forms blank app template with only UWP selected
• Affected Devices: Desktop

Environment

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Workaround

You could try Syncfusion's SfTabView for UWP.

[rachelkang]

Hi, @CMarcher - thanks for submitting this issue! Confirming that I'm able to repro this behavior on UWP (works as expected on iOS) Issue13663.zip

[rachelkang]

cc @rmarinho

[Only-Xam]

Issue persist since 4.6 version and raised couple of times. #10950

[YiannisBourkelis]

@jsuarezruiz Same problem here. Carouselview is not working at all on UWP. Clicking on the left or right arrows displays only a small part of the containing view.

[DRAirey1]

I'm running Xamarin.Forms 5.0 and running into the same issue. This control is buggy as hell in UWP.

[hammondreg]

This control is buggy as hell in UWP <= You wait until you start to try it in MAUI!