ChooseContactRenderer.cs

using UIKit;
using AddressBookUI;
using Xamarin.Forms;
using Xamarin.Forms.Platform.iOS;
using contact_picker;
using contact_picker.iOS;

[assembly: ExportRenderer (typeof(ChooseContactPage), typeof(ChooseContactRenderer))]

namespace contact_picker.iOS
{
    public partial class ChooseContactRenderer : PageRenderer
    {
        ABPeoplePickerNavigationController _contactController;

        public string type_number;

        protected override void OnElementChanged (VisualElementChangedEventArgs e)
        {
            base.OnElementChanged (e);

            var page = e.NewElement as ChooseContactPage;

            if (e.OldElement != null || Element == null) {
                return;

            }

        }

        public override void ViewDidLoad ()
        {
            base.ViewDidLoad ();

            _contactController = new ABPeoplePickerNavigationController ();

            this.PresentModalViewController (_contactController, true); //display contact chooser

            _contactController.Cancelled += delegate {
                Xamarin.Forms.Application.Current.MainPage.Navigation.PopModalAsync ();

                this.DismissModalViewController (true); };

            _contactController.SelectPerson2 += delegate(object sender, ABPeoplePickerSelectPerson2EventArgs e) {

                var getphones = e.Person.GetPhones();
                string number = "";

                if (getphones == null)
                {
                    number = "Nothing";
                }
                else if (getphones.Count > 1)
                {
                    //il ya plus de 2 num de telephone
                    foreach(var t in getphones)
                    {
                        number = t.Value + "/" + number;
                    }
                }
                else if (getphones.Count == 1)
                {
                    //il ya 1 num de telephone
                    foreach(var t in getphones)
                    {
                        number = t.Value;
                    }
                }

                Xamarin.Forms.Application.Current.MainPage.Navigation.PopModalAsync ();

                var twopage_renderer = new MyPage();
                MessagingCenter.Send<MyPage, string> (twopage_renderer, "num_select", number);
                this.DismissModalViewController (true);

            };
        }

        public override void ViewDidUnload ()
        {
            base.ViewDidUnload ();

            // Clear any references to subviews of the main view in order to
            // allow the Garbage Collector to collect them sooner.
            //
            // e.g. myOutlet.Dispose (); myOutlet = null;

            this.DismissModalViewController (true);
        }

        public override bool ShouldAutorotateToInterfaceOrientation (UIInterfaceOrientation toInterfaceOrientation)
        {
            // Return true for supported orientations
            return (toInterfaceOrientation != UIInterfaceOrientation.PortraitUpsideDown);
        }
    }
}