RadioButtons control does not support keyboard navigation in XAML islands

Describe the bug

The RadioButtons control (which is used to group multiple radio button controls together allows navigation as follows-

• Pressing tab into the radio buttons control should bring focus to the selected radio button. If no radio button is selected, pressing tab should bring focus to the first radio button.
• Pressing tab again takes focus out of the radio buttons control. However, to navigate within the radio buttons, the arrow keys are used. This is the built in expected behavior.

However, when the radio buttons control is used within XAML islands, pressing tab always takes the focus to the first item (not to the selected item). Keyboard navigation does not work.

Steps to reproduce the bug

Steps to reproduce the behavior:

1. Try to tab navigate and arrow navigate in this user control within a XAML island. The keyboard navigation does not work as expected.

<UserControl
    x:Class="Microsoft.PowerToys.Settings.UI.Views.ShellPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:behaviors="using:Microsoft.PowerToys.Settings.UI.Behaviors"
    xmlns:winui="using:Microsoft.UI.Xaml.Controls"
    xmlns:helpers="using:Microsoft.PowerToys.Settings.UI.Helpers"
    xmlns:views="using:Microsoft.PowerToys.Settings.UI.Views"
    xmlns:ic="using:Microsoft.Xaml.Interactions.Core"
    xmlns:i="using:Microsoft.Xaml.Interactivity"
    xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
    mc:Ignorable="d">


    <Grid>
        <muxc:RadioButtons>
            <RadioButton>Item 1</RadioButton>
            <RadioButton>Item 2</RadioButton>
            <RadioButton>Item 3</RadioButton>
        </muxc:RadioButtons>
    </Grid>
</UserControl>

Expected behavior

Screenshots

However, this navigation does not work within a XAML island.

Version Info

NuGet package version:

Microsoft.UI.Xaml.2.5.0-prerelease.200708003

Windows app type: UWP app within a XAML Island.

UWP	Win32
Yes

Windows 10 version	Saw the problem?
Insider Build (xxxxx)
May 2020 Update (19041)
November 2019 Update (18363)	Yes
May 2019 Update (18362)	Yes
October 2018 Update (17763)
April 2018 Update (17134)
Fall Creators Update (16299)
Creators Update (15063)

Device form factor	Saw the problem?
Desktop	Yes
Xbox
Surface Hub
IoT

Additional context

Link to Issue in the PowerToys Page - https://github.com/microsoft/PowerToys/issues/6032

[StephenLPeters]

@alekhyareddy28 could you please open a second issue for the narrator bug? 😃

[Felix-Dev]

I am currently working on the RadioButtons control so I could take a look at this narrator issue as well while I’m at it.