[kubaflo]

Note

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It would be very helpful if you could test the resulting artifacts from this PR and let us know in a comment if this change resolves your issue. Thank you!

Description of Change

Backports #38915, "Add iPhone Duo support to Controls.Foldable", from squash commit a561eaec4aacbe962416c64491aa5ffbc6bde9ae to inflight/current, as explicitly requested.

Preserves the source implementation: view/window-scoped reserved-region geometry, hinge monitoring and lifecycle cleanup, scene activation support, shared layout refresh, state triggers, sample updates, and Foldable unit tests. Original author and source coauthors are preserved.

The only cherry-pick conflicts were in .github/scripts/RunTests.ps1 and .github/scripts/shared/Detect-TestsInDiff.ps1. Resolution retains this branch's Compatibility test entries and adds the source Foldable mappings. Formatting is scoped to changed C# files; the formatter's unrelated Android null-conditional event rewrite was not retained.

SDK limitation: the source's native Duo path is enabled only for iOS target platform version 27.1+ (or an explicit IosDuoBindingsAvailable override with compatible bindings). This target branch currently defaults to iOS 26.0, so its default build retains fallback behavior rather than enabling Duo APIs. This PR does not upgrade the branch-wide SDK/workload or remove capability/runtime guards. Publishing actual Duo-enabled artifacts requires a compatible iOS 27.1 SDK build configuration.

Validation run in this backport worktree using .NET SDK 11.0.100-preview.6.26359.118, targeting this branch's net10.0 TFMs, and Xcode 26.6:

Command	Result
dotnet test src/Controls/Foldable/test/Controls.Foldable.UnitTests.csproj --nologo --verbosity minimal	Passed: 39, failed: 0, skipped: 0; rerun after formatting and normal restore.
dotnet build src/Controls/Foldable/src/Controls.Foldable.csproj -f net10.0-ios26.0 --nologo --verbosity minimal	Passed: 0 warnings, 0 errors.
dotnet build src/Controls/Foldable/src/Controls.Foldable.csproj -f net10.0-maccatalyst26.0 --no-restore --nologo --verbosity minimal	Passed: 0 warnings, 0 errors.
dotnet build src/Controls/Foldable/src/Controls.Foldable.csproj -f net10.0-android36.0 --no-restore --nologo --verbosity minimal	Passed: 3 Gradle Java 8 obsolescence warnings, 0 errors.
dotnet build src/Controls/Foldable/src/Controls.Foldable.csproj -f net10.0-ios27.1 -p:TargetFrameworks=net10.0-ios27.1 --nologo --verbosity minimal	Blocked: NETSDK1140, local SDK supports iOS 26.0/26.5, not 27.1.
git diff --cached --check	Passed.
git diff --check	Passed.

Formatting command (passed; changed_files contains staged changed .cs paths):

changed_files=()
while IFS= read -r file; do changed_files+=("$file"); done < <(git diff --cached --name-only -- '*.cs')
dotnet format Microsoft.Maui.sln --no-restore --exclude Templates/src --exclude-diagnostics CA1822 --include "${changed_files[@]}" --verbosity quiet

PowerShell syntax check (passed for all three source script files):

$files=@(".github/scripts/RunTests.ps1", ".github/scripts/shared/Detect-TestsInDiff.ps1", ".github/scripts/shared/Detect-TestsInDiff.Tests.ps1")
foreach ($file in $files) {
    $tokens=$null; $errors=$null
    [System.Management.Automation.Language.Parser]::ParseFile((Join-Path $PWD $file), [ref]$tokens, [ref]$errors) > $null
    if ($errors.Count) { $errors | Write-Error; exit 1 }
    Write-Output "Parsed $file"
}

Build/test/format subprocesses ran with GH_TOKEN, GITHUB_TOKEN, and COPILOT_GITHUB_TOKEN removed from their environments. A --no-restore test attempt after the explicit 27.1 restore probe encountered changed assets; normal restore and the full 39-test rerun above succeeded.

Not run: native iOS 27.1/Duo compilation or simulator/device runtime validation, sample app build/runtime validation, Windows validation, or pipeline Pester tests. No XCTest or host UI automation was used. Source PR validation is not claimed as a result of this backport.

Issues Fixed

Backport of #38915; no separate issue.