如果使用 shell 导航，请创建CustomShellRenderer

[assembly: ExportRenderer(typeof(AppShell), typeof(CustomShellRenderer))]
namespace Droid.Renderers.CustomAppShell
{
    public class CustomShellRenderer : ShellRenderer
    {
        protected override IShellToolbarAppearanceTracker CustomToolbarAppearanceTracker()
        {
            return new CustomShellToolbarAppearanceTracker(this);
        }
    }
}
        
namespace Droid.CustomShell
{
    public class CustomShellToolbarAppearanceTracker : ShellToolbarAppearanceTracker
    {
        public override void SetAppearance(AndroidX.AppCompat.Widget.Toolbar toolbar, IShellToolbarTracker toolbarTracker, ShellAppearance appearance)
        {
            base.SetAppearance(toolbar, toolbarTracker, appearance);
            toolbar.NavigationContentDescription = "Custom Label Description”; // Set label here
        }
    }
}