Object/instance exception when accessing listview column
===

I am using WinForms/VS2010 c# to create a listview with 12 columns and 8 rows.  Here is the snippet from the WinForms auto-coded file:   

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.listView1 = new System.Windows.Forms.ListView();
           .....
        } 

 Then, in the Form1.cs file, I have the following method:

        // in my form1.cs file
        public void listView1_Populate()
        {
            var columnIndex = listView1.Columns[2].Index;
            int counter = 0;

            foreach (ListViewItem item in listView1.Items)
            {
                 if (item.SubItems[columnIndex].Text == "2")
                  {
                       counter += 100;
                       item.SubItems[columnIndex].Text = counter.ToString(); 
                
                  }
            }
        }

But I get the "Object reference not set to an instance of an object" exception when the code hits the line:  var columnIndex = listView1.Columns[2].Index;
What am I doing wrong (other than trying to learn c# at age 54!)