Fix ShellItems and MenuItems not displaying on Android when Flyout is presented, for both custom and default templates

[SuthiYuvaraj]

Note

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Issue Description

Shell.MenuItem and ShellItem do not render correctly on Android when FlyoutIsPresented is set to true, affecting both templated and non-templated scenarios.

Root Cause

The FlyoutContent was not created in time because the flyout was already presented before the associated template or view had a chance to load.

Description of Change

Added logic in OnFlyoutViewLayoutChanging to ensure that the flyout content is properly initialised and reloaded when necessary, even if the flyout is already visible. This ensures that both templated and non-templated views render as expected.

Issues Fixed

Fixes #21963

Tested the behaviour in the following platforms

• Android
• Windows
• iOS
• Mac

Output Screenshot

Before Issue Fix	After Issue Fix

[dotnet-policy-service]

Hey there @@SuthiYuvaraj! Thank you so much for your PR! Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[Copilot]

Pull Request Overview

This PR ensures that ShellItem and MenuItem entries render correctly on Android when FlyoutIsPresented is set, by updating the renderer logic and adding end-to-end tests and a HostApp sample.

• Updated Android ShellFlyoutTemplatedContentRenderer to reload flyout content when FlyoutIsPresented is true.
• Added a HostApp sample (Issue21963) that presents the flyout with both item and menu templates applied.
• Introduced a shared UI test (Issue21963) verifying all shell content and menu items appear initially.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue21963.cs	New UI test asserting presence of shell content and menu items.
src/Controls/tests/TestCases.HostApp/Issues/Issue21963.cs	HostApp test page setting FlyoutIsPresented, templates, and items.
src/Controls/src/Core/Compatibility/Handlers/Shell/Android/ShellFlyoutTemplatedContentRenderer.cs	Renderer change to call UpdateFlyoutContent when flyout is already open.

Comments suppressed due to low confidence (2)

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue21963.cs:1

• [nitpick] The preprocessor macro name is confusing and singular; consider renaming to TESTS_FAIL_ON_WINDOWS or using an NUnit [Platform] or [Category] attribute to exclude Windows-specific tests.

#if TEST_FAILS_ON_WINDOWS// This test fails on Windows: Shell.MenuItemTemplate behaves correctly,AutomationId does not work as expected on the Windows platform.

src/Controls/src/Core/Compatibility/Handlers/Shell/Android/ShellFlyoutTemplatedContentRenderer.cs:442

• Since the renderer now reacts to FlyoutIsPresented, please update the corresponding XML docs in /docs/ to describe this new behavior.

			if ((_initialLayoutChangeFired || FlyoutView.FlyoutBehavior == FlyoutBehavior.Locked || _shellContext.Shell.FlyoutIsPresented) &&