[.Net 10] Shell.SetNavBarVisibilityAnimationEnabled property

[kubaflo]

Description of Change

<Tab Shell.NavBarVisibilityAnimationEnabled="True">
    <ShellContent
                    Title="Home"
                    ContentTemplate="{DataTemplate local:MainPage}"
                    Route="MainPage"/>
</Tab>

This PR introduces a new public property: NavBarVisibilityAnimationEnabled

For now, the implementation only applies to iOS. If support for Android/Windows is desired in the future, it can be added separately.

NavBarVisibilityAnimationEnabled is a bool property added to Shell. It controls whether the navigation bar's visibility changes are animated. The default value is true to preserve existing behavior.

Issues Fixed

Fixes #26994

Demo

public MainPage()
{
	InitializeComponent();
	var setHasNavigationBarSwitch = new Switch() { IsToggled = true };
	setHasNavigationBarSwitch.Toggled += (s, e) => Shell.SetNavBarIsVisible(this, e.Value);
	var setNavigationBarHiddenAnimation = new Switch() { IsToggled = true };
	setNavigationBarHiddenAnimation.Toggled += (s, e) => Shell.SetNavBarVisibilityAnimationEnabled(this, e.Value);

	Content = new VerticalStackLayout
	{
		Spacing = 5,
		Children =
			{
				new HorizontalStackLayout
				{
					Children =
					{
						new Label {
							Text = "NavigationPage.SetHasNavigationBar: ",
						},
						setHasNavigationBarSwitch,
					}
				},
				new HorizontalStackLayout
				{
					Children =
					{
						new Label {
							Text = "Page.NavigationBarHiddenAnimation: ",
						},
						setNavigationBarHiddenAnimation,
					}
				}
			}
	};
}

[dotnet-policy-service]

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 introduces a new public property, NavBarVisibilityAnimationEnabled, to control whether navigation bar visibility changes are animated (currently only implemented for iOS). The key changes include:

• Adding the new attached BindableProperty and its getter/setter in Shell.cs with XML documentation.
• Updating PublicAPI.Unshipped.txt files across multiple platforms to include the new public API.
• Propagating the property in property propagation logic and using its value in iOS renderers to drive the navigation bar animation behavior.

Reviewed Changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/Controls/src/Core/Shell/Shell.cs	Added NavBarVisibilityAnimationEnabled property and related API methods.
src/Controls/src/Core/PublicAPI/...	Updated public API definitions to reflect the newly added property.
src/Controls/src/Core/Internals/PropertyPropagationExtensions.cs	Propagated the new property from parent elements.
src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellSectionRenderer.cs	Updated navigation bar hide logic to use the new animation flag.
src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellItemRenderer.cs	Incorporated the new property in updating navigation bar appearance.

Files not reviewed (1)

• src/Controls/src/Core/PublicAPI/net-tizen/PublicAPI.Unshipped.txt: Language not supported

[Copilot]

Consider updating the documentation to explicitly mention that the current implementation of NavBarVisibilityAnimationEnabled only applies to iOS and does not affect Android/Windows behavior.

Suggested change

	/// Determines if the navigation bar visibility change should be animated.
	/// Determines if the navigation bar visibility change should be animated.
	/// This property is currently only applicable on iOS and does not affect behavior on Android or Windows.

[Copilot]

Ensure that tests in TestCases.HostApp and TestCases.Shared.Tests cover the behavior of the new NavBarVisibilityAnimationEnabled property, especially to verify that navigation bar animations behave as expected on iOS.