MvvmCross LegacyBar implementation. I had to build the library from GitHub rather than using the Component from the Xamarin make sure you switch to the eventmenu branch or this will not work

MvxLegacyBarActivity.cs

using System;
using Android.App;
using Android.Content;
using Android.Views;
using Cirrious.MvvmCross.Droid.Views;
using LegacyBar.Library.BarBase;

namespace BarcodeWars.Droid.Controls
{
	public class MvxLegacyBarActivity : MvxActivity
	{
		public MvxLegacyBarActivity ()
		{
		}

		public LegacyBar.Library.Bar.LegacyBar LegacyBar { get; set; }
		public int MenuId { get; set; }

		public override bool OnPrepareOptionsMenu(IMenu menu)
		{
			if (LegacyBar == null)
				return base.OnPrepareOptionsMenu(menu);

			menu.Clear();
			MenuInflater.Inflate(MenuId, menu);

			for (var i = 0; i < menu.Size(); i++)
			{
				var menuItem = menu.GetItem(i);
				menuItem.SetVisible(!LegacyBar.MenuItemsToHide.Contains(menuItem.ItemId));
			}
			return base.OnPrepareOptionsMenu(menu);
		}

		public override bool OnCreateOptionsMenu(IMenu menu)
		{
			if (MenuId > 0)
				MenuInflater.Inflate(MenuId, menu);

			return base.OnCreateOptionsMenu(menu);
		}

		public void AddHomeAction(Type activity, int resId)
		{
			LegacyBarActivityUtils.AddHomeAction(LegacyBar, this, activity, resId);
		}

		public void AddHomeAction(Action action, int resId, bool isHomeAsUpEnabled = true)
		{
			LegacyBarActivityUtils.AddHomeAction(LegacyBar, action, resId, isHomeAsUpEnabled);
		}
	}
}