using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
 
namespace WindowsFormsApplication1
{
 
    public class frmBack : System.Windows.Forms.Form
    {
        private bool InstanceFieldsInitialized = false;
 
        public frmBack()
        {
            if (!InstanceFieldsInitialized)
            {
                InitializeInstanceFields();
                InstanceFieldsInitialized = true;
            }
            SubscribeToEvents();
        }
 
        private void InitializeInstanceFields()
        {
            btnstart = new Button
            {
                Parent = this,
                Text = "Start"
            };
            lbo = new ListBox
            {
                Parent = this,
                Top = 50
            };
        }
 
 
        //Interne Klasse
        private class Back
        {
 
            //Öffentliche Liste          
            public List<string> lst = new List<string>();
            public delegate void FilledEventHandler();
 
            //Melde-Ereignis
            public event FilledEventHandler Filled;
 
 
            //Öffentliche Methode: Liste füllen
            public void fill()
            {
                System.Threading.Thread th = new System.Threading.Thread(iFill);
                //Füllender Thread
                th.Start();
            }
 
            //Interne Methode
            private void iFill()
            {
                lst.Clear();
                for (int i = 0; i <= 10; i++)
                {
                    lst.Add("Item" + i.ToString());
                }
                if (Filled != null)
                    Filled();
            }
        } //Back-Klasse
 
 
        //Controls in der Hauptform
        private Button btnstart;
        private ListBox lbo;
 
        //Instanz der internen Klasse
        private Back bck = new Back();
 
 
        //Click-Eventhandler
        private void btnstart_Click(object sender, System.EventArgs e)
        {
 
            lbo.DataSource = null;
            bck.fill();
        }
 
 
        //Filled-Eventhandker (von bck ausgelöstes Event)
        private void bck_Filled()
        {
            //Invoke: ZUgriff auf Control aus anderem Thread
            this.Invoke(new MethodInvoker(BindList));
        }
 
 
        private void BindList()
        {
            lbo.DataSource = bck.lst;
        }
 
 
        //Event handler
        private bool EventsSubscribed = false;
        private void SubscribeToEvents()
        {
            if (EventsSubscribed)
                return;
            else
                EventsSubscribed = true;
 
            btnstart.Click += btnstart_Click;
            bck.Filled += bck_Filled;
        }
 
 
        private void InitializeComponent()
        {
            this.SuspendLayout();
            // 
            // frmBack
            // 
            this.ClientSize = new System.Drawing.Size(292, 273);
            this.Name = "frmBack";
            this.Load += new System.EventHandler(this.frmBack_Load);
            this.ResumeLayout(false);
 
        }
 
 
        private void frmBack_Load(object sender, EventArgs e)
        {
            //formal
        }
 
    } //Formular
}//Namespace