Label does not display text - Xamarin IOS
<p>I'm doing a countdown which should display a label in the count, but the label (lblMostrador) on my viewcontroller does not display the text.
The code is right because the output box displays the count correctly.
Is there any special configuration or else for the label work?</p>

<p>partial class EsquerdaViewController : UIViewController
    {</p>

<pre><code>    private System.Timers.Timer aTimer;
    private DateTime tempo   = new DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day, 0, 1, 0);
    private DateTime tempo2  = new DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day, 0, 0, 1);


    public EsquerdaViewController (IntPtr handle) : base (handle)
    {
    }

    public override void ViewDidLoad()
    {
        base.ViewDidLoad ();
        Console.WriteLine ("Testando...");

        btnVoltar.TouchUpInside += (sebder, e) =&gt; 
        {
            NavigationController.PopViewController(true);
        };


        btnIniciar.TouchUpInside += (sender, e) =&gt;
        {
            aTimer = new System.Timers.Timer(1000);

            aTimer.Elapsed += OnTimedEvent;

            aTimer.AutoReset = true;

            aTimer.Enabled = true;

        };


    }

    private void OnTimedEvent(Object source, System.Timers.ElapsedEventArgs e)
    {
        System.TimeSpan diff1   = tempo.Subtract(tempo2);

        if (diff1.Minutes == 0 &amp;&amp; diff1.Seconds == 0)
            aTimer.Stop();

        DateTime tempoNovo      = new DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day, 0, diff1.Minutes, diff1.Seconds);
        tempo                   = tempoNovo;
        Console.WriteLine (String.Format("{0:00}:{1:00}", diff1.Minutes, diff1.Seconds));
        lblMostrador.Text = String.Format ("{0:00}:{1:00}", diff1.Minutes, diff1.Seconds);
    }
}
</code></pre>