ViewRenderer for iOS - view.Frame is not correct

I have a forms application and created a ViewRenderer for iOS. I need to get the frame of that view, but the Frame X and Y is wrong (depending a bit on how I lay them out in the Xaml how much wrong).

It seams like I it gets it X an Ys before all layout has re-sized it self ?

Getting extremely frustrated with this! Anyone any tips or ideas ?

Her is some code - CustomRenderer in iOS

using System;
using System.Collections.Generic;
using System.Windows.Input;
using CoreGraphics;
using Test.CustomViews;
using Test.iOS.CustomRendere;
using Foundation;
using UIKit;
using Xamarin.Forms;
using Xamarin.Forms.Platform.iOS;

[assembly: ExportRenderer(typeof(PopupListSelector), typeof(CustomPopupListSelectorRenderer))]
namespace Test.iOS.CustomRendere
{
    public class CustomPopupListSelectorRenderer: ViewRenderer
    {
    UIViewController viewController;

    public override void TouchesBegan(Foundation.NSSet touches, UIEvent evt)
    {
        base.TouchesBegan(touches, evt);
        ShowPopup();
    }

        public void ShowPopup()
        {
            var topController = SetTopViewController();

        viewController = new UIViewController();
            UIPopoverPresentationController pc = (UIPopoverPresentationController)viewController.PresentationController;

        //this.SetNeedsLayout();
        //this.LayoutIfNeeded();

        pc.SourceView = topController.View;
        pc.SourceRect = this.Frame;
        pc.PermittedArrowDirections = UIPopoverArrowDirection.Left;

        UITableView table = new UITableView(new CGRect(0, 0, 300, 300));
        table.CellLayoutMarginsFollowReadableWidth = false;

        viewController.Add(table);
        topController.PresentViewController(viewController, true, null);
    }

    private UIViewController SetTopViewController()
        {
        var topController = UIApplication.SharedApplication.KeyWindow.RootViewController;

        while (topController.PresentedViewController != null)
        {
            topController = topController.PresentedViewController;
        }

            return topController;
        }
    }
}

Her is the ContentView in the PCL

using System;
using System.Collections.Generic;
using System.Windows.Input;
using Xamarin.Forms;

namespace Test.CustomViews
{
    public class PopupListSelector : ContentView
    {
        private readonly Label textLabel;
        private readonly Label itemSelectedText;
        private readonly StackLayout stacklayout;

        public PopupListSelector()
        {
                stacklayout = new StackLayout()
                    {
                        Orientation = StackOrientation.Horizontal,
                        HorizontalOptions = LayoutOptions.FillAndExpand,
                        VerticalOptions = LayoutOptions.Center,
                        Padding = new Thickness(5),
                };
            textLabel = new Label { Text = Text, HorizontalOptions = LayoutOptions.FillAndExpand };
            itemSelectedText = new Label { Text = Text, HorizontalOptions = LayoutOptions.End};

            stacklayout.Children.Add(textLabel);
            stacklayout.Children.Add(itemSelectedText);

            Content = stacklayout;
        }

        public string Text
        {
            get { return (string)GetValue(TextProperty); }
            set
            {
                SetValue(TextProperty, value);
                textLabel.Text = value;
            }
        }



    public static BindableProperty TextProperty = BindableProperty.Create(nameof(Text), typeof(string), typeof(PopupListSelector), string.Empty,
                             BindingMode.TwoWay, null, (bindable, oldValue, newValue) =>
    {
        var ctrl = (PopupListSelector)bindable;
        ctrl.Text = (string)newValue;
    });
    }
}

and the Xaml

<?xml version="1.0" encoding="utf-8" ?>
<popup:PopupPage xmlns="http://xamarin.com/schemas/2014/forms"
                 xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
                 xmlns:popup="clr-namespace:Rg.Plugins.Popup.Pages;assembly=Rg.Plugins.Popup"
                 xmlns:animations="clr-namespace:Rg.Plugins.Popup.Animations;assembly=Rg.Plugins.Popup"
                 xmlns:views="clr-namespace:CornerStone.CustomViews;assembly=CornerStone"
                 x:Class="Test.Views.Page">
    <popup:PopupPage.Animation>
        <animations:ScaleAnimation
            PositionIn="Center"
            PositionOut="Center"
            ScaleIn="1.2"
            ScaleOut="0.8"
            DurationIn="400"
            DurationOut="300"
            EasingIn="SinOut"
            EasingOut="SinIn"
            HasBackgroundAnimation="True"/>
    </popup:PopupPage.Animation>
    <Grid BackgroundColor="White">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="24*"/>
            <ColumnDefinition Width="1"/>
            <ColumnDefinition Width="75*"/>
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <ScrollView Grid.Row="0" Grid.Column="0" Orientation="Vertical" HorizontalOptions="FillAndExpand">

             <views:PopupListSelector
                            Text = "TEST">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST2">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST3">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST4">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST5">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST6">
                   </views:PopupListSelector>

        </ScrollView>
        <BoxView Grid.Row="1" Grid.Column="1" Grid.RowSpan="2" WidthRequest="1" VerticalOptions="FillAndExpand"/>
        <StackLayout Grid.Row="1" Grid.Column="2" Orientation="Vertical">

             <views:PopupListSelector
                            Text = "TEST7">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST8">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST9">
                   </views:PopupListSelector>
             <views:PopupListSelector
                            Text = "TEST10">
                   </views:PopupListSelector>
        </StackLayout>

    </Grid>
</popup:PopupPage>