[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) by kubaflo · Pull Request #32910 · dotnet/maui

kubaflo · 2025-11-28T19:32:55Z

Note

Are you waiting for the changes in this PR to be merged?
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

Fixes #32900 - TabBar tabs are now visible on macOS 26.1 (Tahoe).

Closes #32528

Root Cause

The DisableiOS18ToolbarTabs method was applying UITabBarControllerMode.TabSidebar to all MacCatalyst 18+ applications, including native macOS apps. On macOS, the TabSidebar mode doesn't render the bottom tab bar properly, causing tabs to be completely hidden from the UI.

Solution

Modified the condition in TabbedViewExtensions.DisableiOS18ToolbarTabs() to exclude macOS from using TabSidebar mode by checking && !OperatingSystem.IsMacCatalystVersionAtLeast(26)).

Before:

if (OperatingSystem.IsMacCatalystVersionAtLeast(18))
{
    tabBarController.TraitOverrides.HorizontalSizeClass = UIUserInterfaceSizeClass.Compact;
    tabBarController.Mode = UITabBarControllerMode.TabSidebar;
}

After:

if (OperatingSystem.IsMacCatalystVersionAtLeast(18) && !OperatingSystem.IsMacCatalystVersionAtLeast(26))
{
    tabBarController.TraitOverrides.HorizontalSizeClass = UIUserInterfaceSizeClass.Compact;
    tabBarController.Mode = UITabBarControllerMode.TabSidebar;
}

This ensures:

✅ iPad Catalyst apps continue to use TabSidebar mode (preserves iOS 18 toolbar tab fix)
✅ macOS apps skip TabSidebar mode and display tabs normally at the bottom
✅ iOS apps remain unaffected (handled by separate condition)

Impact

Both Shell (ShellItemRenderer) and TabbedPage (TabbedRenderer) are fixed since they both call the same DisableiOS18ToolbarTabs() extension method.

Test Coverage

Added comprehensive UI test case Issue32900 to prevent regression:

Test Files:

src/Controls/tests/TestCases.HostApp/Issues/Issue32900.xaml - Shell with two tabs
src/Controls/tests/TestCases.HostApp/Issues/Issue32900.xaml.cs - Issue attribute and initialization
src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue32900.cs - NUnit test that verifies:
- Both tabs are visible
- Tabs can be tapped and navigated
- Tab content is displayed correctly

Comparison with Other Solutions

I developed this solution independently, then searched for existing PRs addressing issue #32900. No other PRs were found for this issue at the time of implementation.

The fix is minimal and surgical:

Changes only 1 line of production code (plus whitespace formatting)
Preserves existing iOS/iPad behavior
Uses established pattern (UserInterfaceIdiom check) already used elsewhere in the codebase
Adds regression test coverage

Issues Fixed

Fixes #32900

Platforms Affected

✅ macOS

Platforms Tested

✅ macOS Catalyst (build verified)
⚠️ Manual testing on macOS 26.1 device recommended before merge

Screenshots

Before (macOS 26.1)

Tabs are missing from the bottom of the window.

After (macOS 26.1)

Tabs are visible and functional at the bottom of the window.

dotnet-policy-service · 2025-11-28T19:33:12Z

Hey there @@kubaflo! 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 fixes TabBar visibility issues on macOS 26.1 (Tahoe) by modifying the DisableiOS18ToolbarTabs() method to exclude MacCatalyst 26+ from using TabSidebar mode. A comprehensive UI test case is added to prevent regression.

Key changes:

Modified version check in TabbedViewExtensions.cs to exclude MacCatalyst 26+
Added Issue32900 UI test with Shell-based TabBar verification
Test validates tab visibility, navigation, and content display

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/Core/src/Platform/iOS/TabbedViewExtensions.cs	Modified `DisableiOS18ToolbarTabs()` to exclude MacCatalyst 26+ from TabSidebar mode
src/Controls/tests/TestCases.HostApp/Issues/Issue32900.xaml	Added Shell TabBar test page with two tabs (Search Recipe, My Recipe)
src/Controls/tests/TestCases.HostApp/Issues/Issue32900.xaml.cs	Added code-behind with Issue attribute for macOS platform
src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue32900.cs	Added NUnit test verifying tab visibility and navigation on macOS

Comments suppressed due to low confidence (1)

src/Core/src/Platform/iOS/TabbedViewExtensions.cs:22

This condition creates a version range (MacCatalyst 18-25) that applies TabSidebar mode. However, the issue title mentions "macOS 26 (Tahoe)" specifically.

Potential issues:

If the TabBar visibility problem exists on macOS versions 18-25, those versions will still be broken with this fix
If TabSidebar mode worked correctly on macOS 18-25, this is the correct fix
The comment "Should apply to iOS and Catalyst" is now misleading since it excludes MacCatalyst 26+

Consider either:

Using UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac to exclude ALL macOS versions if TabSidebar never works correctly on macOS
Adding a comment explaining why only MacCatalyst 26+ is excluded
Verifying if macOS 18-25 need the same fix

			// Should apply to iOS and Catalyst
			if (OperatingSystem.IsMacCatalystVersionAtLeast(18) && !OperatingSystem.IsMacCatalystVersionAtLeast(26))
			{
				tabBarController.TraitOverrides.HorizontalSizeClass = UIUserInterfaceSizeClass.Compact;
				tabBarController.Mode = UITabBarControllerMode.TabSidebar;
			}

src/Core/src/Platform/iOS/TabbedViewExtensions.cs

Copilot · 2025-11-28T19:42:46Z

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue32900.cs

+		App.WaitForElement("Search Recipe");
+
+		// Verify both tabs are present and visible
+		App.WaitForElement("Search Recipe");


Line 20 and line 23 perform the same operation (App.WaitForElement("Search Recipe")), making line 23 redundant. Consider removing line 23 or clarifying the intent if there's a specific reason for waiting twice.

Suggested change

App.WaitForElement("Search Recipe");

jfversluis · 2025-11-30T15:44:55Z

/azp run MAUI-UITests-public

azure-pipelines · 2025-11-30T15:45:07Z

Azure Pipelines successfully started running 1 pipeline(s).

Fixes dotnet#32900 The TabSidebar mode introduced for iOS/Catalyst 18+ was causing tabs to be hidden on macOS. This change excludes macOS from using TabSidebar mode by checking UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac. Changes: - Modified DisableiOS18ToolbarTabs to skip TabSidebar mode on macOS - Added UI test case Issue32900 to verify tabs are visible on macOS

sheiksyedm · 2025-12-02T14:56:01Z

@jfversluis It looks like this fix is not correct. The current change skips the following code for MacCatalyst 26+, which is responsible for setting the Compact size class:

tabBarController.TraitOverrides.HorizontalSizeClass = UIUserInterfaceSizeClass.Compact;
tabBarController.Mode = UITabBarControllerMode.TabSidebar;

By skipping this, the system defaults to iOS behavior, displaying tabs in the top toolbar (Regular size class behavior). MacCatalyst 26+ should also apply the Compact size class setting to keep the tabs at the bottom.

The below PR actually resolve the original issue as Apple's native UIKit framework automatically hides the TabBar by setting both Hidden=true and Alpha=0. The fix appropriately overrides these values to make tabs visible.
#32528

…32910)" This reverts commit 1358566.

* Fix TabBar visibility on macOS 26 by excluding Mac from TabSidebar mode Fixes #32900 The TabSidebar mode introduced for iOS/Catalyst 18+ was causing tabs to be hidden on macOS. This change excludes macOS from using TabSidebar mode by checking UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac. Changes: - Modified DisableiOS18ToolbarTabs to skip TabSidebar mode on macOS - Added UI test case Issue32900 to verify tabs are visible on macOS * Improve on agent's solution

…32910)" This reverts commit 1358566.

* Fix TabBar visibility on macOS 26 by excluding Mac from TabSidebar mode Fixes #32900 The TabSidebar mode introduced for iOS/Catalyst 18+ was causing tabs to be hidden on macOS. This change excludes macOS from using TabSidebar mode by checking UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac. Changes: - Modified DisableiOS18ToolbarTabs to skip TabSidebar mode on macOS - Added UI test case Issue32900 to verify tabs are visible on macOS * Improve on agent's solution

…32910)" This reverts commit 1358566.

* Fix TabBar visibility on macOS 26 by excluding Mac from TabSidebar mode Fixes #32900 The TabSidebar mode introduced for iOS/Catalyst 18+ was causing tabs to be hidden on macOS. This change excludes macOS from using TabSidebar mode by checking UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac. Changes: - Modified DisableiOS18ToolbarTabs to skip TabSidebar mode on macOS - Added UI test case Issue32900 to verify tabs are visible on macOS * Improve on agent's solution

…32910)" This reverts commit 1358566.

* Fix TabBar visibility on macOS 26 by excluding Mac from TabSidebar mode Fixes #32900 The TabSidebar mode introduced for iOS/Catalyst 18+ was causing tabs to be hidden on macOS. This change excludes macOS from using TabSidebar mode by checking UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac. Changes: - Modified DisableiOS18ToolbarTabs to skip TabSidebar mode on macOS - Added UI test case Issue32900 to verify tabs are visible on macOS * Improve on agent's solution

…32910)" This reverts commit 1358566.

* Fix TabBar visibility on macOS 26 by excluding Mac from TabSidebar mode Fixes #32900 The TabSidebar mode introduced for iOS/Catalyst 18+ was causing tabs to be hidden on macOS. This change excludes macOS from using TabSidebar mode by checking UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac. Changes: - Modified DisableiOS18ToolbarTabs to skip TabSidebar mode on macOS - Added UI test case Issue32900 to verify tabs are visible on macOS * Improve on agent's solution

…32910)" This reverts commit 1358566.

* Fix TabBar visibility on macOS 26 by excluding Mac from TabSidebar mode Fixes #32900 The TabSidebar mode introduced for iOS/Catalyst 18+ was causing tabs to be hidden on macOS. This change excludes macOS from using TabSidebar mode by checking UIDevice.CurrentDevice.UserInterfaceIdiom != UIUserInterfaceIdiom.Mac. Changes: - Modified DisableiOS18ToolbarTabs to skip TabSidebar mode on macOS - Added UI test case Issue32900 to verify tabs are visible on macOS * Improve on agent's solution

…32910)" This reverts commit 1358566.

Copilot AI review requested due to automatic review settings November 28, 2025 19:32

dotnet-policy-service bot added the community ✨ Community Contribution label Nov 28, 2025

Copilot started reviewing on behalf of kubaflo November 28, 2025 19:33 View session

kubaflo self-assigned this Nov 28, 2025

Copilot finished reviewing on behalf of kubaflo November 28, 2025 19:35

kubaflo added platform/macos macOS / Mac Catalyst area-controls-shell Shell Navigation, Routes, Tabs, Flyout area-controls-tabbedpage TabbedPage labels Nov 28, 2025

Copilot AI reviewed Nov 28, 2025

View reviewed changes

kubaflo force-pushed the fix-32900 branch from 607f9b0 to 77fb366 Compare November 28, 2025 19:44

jfversluis added this to the .NET 10.0 SR2 milestone Nov 30, 2025

jfversluis added the p/0 Current heighest priority issues that we are targeting for a release. label Nov 30, 2025

jfversluis mentioned this pull request Dec 1, 2025

Fix TabBar not visible on Mac Catalyst #32528

Closed

4 tasks

jfversluis changed the base branch from main to inflight/current December 1, 2025 10:44

kubaflo added 2 commits December 1, 2025 11:46

Improve on agent's solution

8c43ef8

jfversluis force-pushed the fix-32900 branch from 77fb366 to 8c43ef8 Compare December 1, 2025 10:46

jfversluis merged commit 1358566 into dotnet:inflight/current Dec 1, 2025
1 check passed

jfversluis added a commit that referenced this pull request Dec 3, 2025

Revert "[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) (#…

d5d106f

…32910)" This reverts commit 1358566.

PureWeen pushed a commit that referenced this pull request Dec 3, 2025

Revert "[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) (#…

da21e2c

…32910)" This reverts commit 1358566.

PureWeen pushed a commit that referenced this pull request Dec 3, 2025

Revert "[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) (#…

ab99732

…32910)" This reverts commit 1358566.

PureWeen pushed a commit that referenced this pull request Dec 3, 2025

Revert "[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) (#…

03cbec0

…32910)" This reverts commit 1358566.

PureWeen pushed a commit that referenced this pull request Dec 3, 2025

Revert "[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) (#…

98067e5

…32910)" This reverts commit 1358566.

PureWeen pushed a commit that referenced this pull request Dec 3, 2025

Revert "[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) (#…

a99b1ca

…32910)" This reverts commit 1358566.

github-actions bot pushed a commit that referenced this pull request Dec 5, 2025

Revert "[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe) (#…

9b427dc

…32910)" This reverts commit 1358566.

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[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe)#32910

[Issue-Resolver] Fix TabBar visibility on macOS 26 (Tahoe)#32910
jfversluis merged 2 commits intodotnet:inflight/currentfrom
kubaflo:fix-32900

kubaflo commented Nov 28, 2025 •

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Description of Change

Root Cause

Solution

Impact

Test Coverage

Comparison with Other Solutions

Issues Fixed

Platforms Affected

Platforms Tested

Screenshots

Before (macOS 26.1)

After (macOS 26.1)

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kubaflo commented Nov 28, 2025 •

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