Page Comparison

namespace TabDemo.Services
{
    using Catel;
    using Catel.IoC;
    using Catel.MVVM;
    using Services;

    public static class ITabServiceExtensions
    {
        public static TabItem Add<TViewModel>(this ITabService tabService, object dataContext = null, bool canClose = false)
            where TViewModel : IViewModel
        {
            Argument.IsNotNull(() => tabService);

            var tabItem = CreateTabItem<TViewModel>(tabService, dataContext);
            tabItem.CanClose = canClose;

            tabService.Add(tabItem);

            return tabItem;
        }

        public static TabItem AddAndActivate<TViewModel>(this ITabService tabService, object dataContext = null, bool canClose = false)
            where TViewModel : IViewModel
        {
            Argument.IsNotNull(() => tabService);

            var tabItem = Add<TViewModel>(tabService, dataContext, canClose);
            tabService.Activate(tabItem);

            return tabItem;
        }

        public static TabItem CreateTabItem<TViewModel>(this ITabService tabService, object dataContext)
            where TViewModel : IViewModel
        {
            Argument.IsNotNull(() => tabService);

            var dependencyResolver = tabService.GetDependencyResolver();
            var viewModelFactory = dependencyResolver.Resolve<IViewModelFactory>();

            var vm = viewModelFactory.CreateViewModel<TViewModel>(dataContext);
            return new TabItem(vm);
        }

        public static void AddAndActivate(this ITabService tabService, TabItem tabItem)
        {
            Argument.IsNotNull(() => tabService);
            Argument.IsNotNull(() => tabItem);

            tabService.Add(tabItem);
            tabService.Activate(tabItem);
        }
    }
}

namespace TabDemo.Services
{
    using System.Linq;
    using System.Windows.Controls;

    public static class TabControlExtensions
    {
        public static bool RemoveAndUpdateSelection(this TabControl tabControl, object tabItem)
        {
            var index = tabControl.Items.IndexOf(tabItem);
            if (index == -1)
            {
                return false;
            }

            var wasSelected = ReferenceEquals(tabControl.SelectedItem, tabItem);

            tabControl.Items.RemoveAt(index);

            if (wasSelected)
            {
                var newIndex = index;
                var newItem = newIndex < tabControl.Items.Count ? tabControl.Items[newIndex] : tabControl.Items.Cast<object>().LastOrDefault(x => x is TabItem);

                tabControl.SelectedItem = newItem;
            }

            return true;
        }
    }
}