WPF controls destroyement

// Author: Ledangkhoa
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Reflection;

namespace WpfApplication9
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            this.Loaded += new RoutedEventHandler(MainWindow_Loaded);
        }

        void MainWindow_Loaded(object sender, RoutedEventArgs e)
        {
            var lis = new WeakListternImp{Name = "Click"};
            WeakImp.AddHandle(button1, lis);

            var lisc = new WeakListternImp { Name = "Checked" };
            WeakImp.AddHandle(checkBox1, lisc);
            var lis2 = new WeakListternImp { Name = "PreviewMouseDoubleClick" };
            WeakImp.AddHandle(button2, lis2);
        }
    }

    class WeakImp : WeakEventManager
    {
       static Dictionary<object,WeakListternImp> hold = null;
       static Dictionary<object, Delegate> dele = null;
        
        internal static void AddHandle(object source, IWeakEventListener handler)
        {
            if (hold == null)
            {
                hold = new Dictionary<object,WeakListternImp>();
                
            }
            hold.Add(source, handler as WeakListternImp);
            Current.ProtectedAddListener(source, handler);

        }
        internal static void RemoveHandle(object source, IWeakEventListener handler)
        {
            Current.ProtectedRemoveListener(source, handler);
        }

        public static WeakImp Current
        {
            get
            {
                WeakImp man = GetCurrentManager(typeof(WeakImp)) as WeakImp;
                if (man == null)
                {
                    man = new WeakImp();
                    SetCurrentManager(typeof(WeakImp), man);
                }
                return man;
            }
        }

        protected override void StartListening(object source)
        {
            Type ty = source.GetType();
            var t = from x in source.GetType().GetEvents();
                    where x.Name == hold[source].Name
                    select x;

            MethodInfo meinf = this.GetType().GetMethod("Active",BindingFlags.Instance| BindingFlags.NonPublic);

            Type typehandler = t.First().EventHandlerType;

            EventInfo eventinfo = t.First();
            if (dele==null)
            {
                dele = new Dictionary<object, Delegate>();
            }
            dele.Add(source,Delegate.CreateDelegate(typehandler,this,meinf));
            eventinfo.AddEventHandler(source, dele[source]);
        }

        void Active(object s, System.EventArgs e)
        {
            DeliverEvent(s, e);
        }


        protected override void StopListening(object source)
        {
            Type ty = source.GetType();
            var t = from x in source.GetType().GetEvents();
                    where x.Name == hold[source].Name
                    select x;

            MethodInfo meinf = this.GetType().GetMethod("Active", BindingFlags.Instance | BindingFlags.NonPublic);

            Type typehandler = t.First().EventHandlerType;

            EventInfo eventinfo = t.First();
            eventinfo.RemoveEventHandler(source, dele[source]);
            hold.Remove(source);
            dele.Remove(source);
            if (hold.Count == 0)
            {
                hold = null;
            }
            if (dele.Count == 0)
            {
                dele = null;
            }
            GC.Collect();
        }
    }
    class WeakListternImp : IWeakEventListener
    {
        public string Name { get; set; }
        public void click(object o, EventArgs e)
        {
            MessageBox.Show(o.ToString()+Name);
            If(Name == "Click")
                WeakImp.RemoveHandle(o, this);

        }
        public bool ReceiveWeakEvent(Type managerType, object sender, EventArgs e)
        {
            click(sender, e);
            
            return true;
        }
    }
}

((Grid)customControl.Parent).Children.Remove(customControl);