How to add items to hosted customComboBox in dataGridView

See more:

C#

I've created a custom winForm comboBox that allows the user to add items by assigning the Text property of the comboBox then adding it to the ItemsCollection...I'm hosting this custom comboBox in a dataGridView as described in http://msdn.microsoft.com/en-us/library/7tas5c80(v=vs.90).aspx[^]

I can't figure out how add items to the hosted comboBox when the user enters data into the dataGridViewCell that host the my custom comboBox.

Can someone please show me what am I missing here and what am I doing incorrectly?

Thanks in advance.
-DA

example:

public class DataGridViewComboBoxEditCell : DataGridViewTextBoxCell //DataGridViewComboBoxCell
    {
        public DataGridViewComboBoxEditCell()
            :base()
        {
            this.Value = "";
        }

        public override void InitializeEditingControl(int rowIndex, object initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
        {
            base.InitializeEditingControl(rowIndex, initialFormattedValue, dataGridViewCellStyle);

            ComboBoxEdit cboEdit = this.DataGridView.EditingControl as ComboBoxEdit;
            
            if (this.Value == null)
            {
                cboEdit.Add((string)this.DefaultNewRowValue);
            }
            else
            {
                cboEdit.Add((string)this.Value);
            }
        }


        public override Type EditType
        {
            get{return typeof(ComboBoxEdit);}
        }

        public override Type ValueType
        {
            get{ return typeof(String);}
        }

        public override object DefaultNewRowValue
        {
            get { return string.Empty; }
        }
    }

 public class ComboBoxEdit : ComboBox, IDataGridViewEditingControl
    {
        DataGridView grid;
        private bool valueChanged = false;
        int rowIndex;

        public ComboBoxEdit()
        {
            this.Text = "";
            this.DrawMode = System.Windows.Forms.DrawMode.OwnerDrawFixed;
            this.DropDownStyle = ComboBoxStyle.DropDown;
        }

        public void Insert(string item)
        {
            if (item != null && item.Length > 0)
            {
                this.Items.Insert(0, item);
                this.Text = "";
            }
        }

        public void Add(string item)
        {
            if (item != null && item.Length > 0)
            {
                this.Items.Add(item);
                this.Text = "";
            }
        }

        protected override void OnSelectedValueChanged(EventArgs e)
        {
            this.Items.RemoveAt(this.SelectedIndex);
            this.Text = "";
        }

        protected override void OnKeyUp(KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter && this.Text.Length > 0)
            {
                Add(this.Text.ToUpper());
            }
        }

        protected override void OnDrawItem(DrawItemEventArgs e)
        {
            if (e.Index < 0)
                return;

            string txt = (string)base.Items[e.Index];

            e.DrawBackground();

            Icon icon = Properties.Resources.delete;

            e.Graphics.DrawImage(icon.ToBitmap(), e.Bounds.X, e.Bounds.Y, 15, 15);

            e.Graphics.DrawString(txt, base.Font, System.Drawing.Brushes.Black, new RectangleF(e.Bounds.X + 15, e.Bounds.Y, e.Bounds.Width, e.Bounds.Height));

            e.DrawFocusRectangle();
        }
 

        // Implmentation of IDataGridViewEditingControl Interface

        // Implementation of properites
        public DataGridView EditingControlDataGridView
        {
            get { return grid; }
            set { grid = value; }
        }

        public object EditingControlFormattedValue
        {
            get{return this.Text;}
            set
            {
                this.Text = (string)value;
                Add((string)value);
            }           
        }

        public int EditingControlRowIndex
        {
            get { return rowIndex; }
            set { rowIndex = value; }
        }

        public bool EditingControlValueChanged
        {
            get { return valueChanged; }
            set { valueChanged = value; }
        }

        public Cursor EditingPanelCursor
        {
            get { return base.Cursor; }
        }

        public bool RepositionEditingControlOnValueChange
        {
            get { return false; }
        }


        // implementation of methods
        public void ApplyCellStyleToEditingControl(
            DataGridViewCellStyle dataGridViewCellStyle)
        {
            //this.Font = dataGridViewCellStyle.Font;
            //this.ForeColor = dataGridViewCellStyle.ForeColor;
            //this.BackColor = dataGridViewCellStyle.BackColor;
        }

        public bool EditingControlWantsInputKey(
            Keys key, bool dataGridViewWantsInputKey)
        {
            //switch (key & Keys.KeyCode)
            //{
            //    case Keys.Left:
            //    case Keys.Up:
            //    case Keys.Down:
            //    case Keys.Right:
            //    case Keys.Home:
            //    case Keys.End:
            //    case Keys.PageDown:
            //    case Keys.PageUp:
            //        return true;
            //    default:
            //        return !dataGridViewWantsInputKey;
            //}
            return false;
        }

        public object GetEditingControlFormattedValue(DataGridViewDataErrorContexts context)
        {
            return EditingControlFormattedValue;
        }

        public void PrepareEditingControlForEdit(bool selectAll)
        {
        }
    }

 public enum CtrlTypes
    {
        Chk,
        Cbo,
        Txt,
        Btn
    }

    public partial class Form1 : Form
    {
        List<CtrlTypes> ct;
        ComboBoxEdit cboEdit;

        public Form1()
        {
            InitializeComponent();

            grid.AllowUserToAddRows = false;
            grid.RowHeadersVisible = false;

            ct = new List<CtrlTypes>();

            int cnt = 0;
            foreach (CtrlTypes cts in Enum.GetValues(typeof(CtrlTypes)))
            {
                DataGridViewRow row = null;
                DataGridViewCell celltype = null;
                DataGridViewTextBoxCell cellname = null;

                switch (cts)
                {
                    case CtrlTypes.Btn:
                        row = new DataGridViewRow();
                        celltype = new DataGridViewButtonCell();
                        celltype.Value = "Btn";
                        cellname = new DataGridViewTextBoxCell();
                        cellname.Value = "Button:";
                        row.Cells.AddRange(new DataGridViewCell[] { cellname, celltype });
                        break;
                    case CtrlTypes.Cbo:
                        row = new DataGridViewRow();
                        celltype = new DataGridViewComboBoxEditCell();
                        //celltype.Value = "GOOG";
                        cellname = new DataGridViewTextBoxCell();
                        cellname.Value = "ComboBx:";
                        row.Cells.AddRange(new DataGridViewCell[] { cellname, celltype });
                        break;
                    case CtrlTypes.Chk:
                        row = new DataGridViewRow();
                        celltype = new DataGridViewCheckBoxCell();
                        celltype.Value = true;
                        cellname = new DataGridViewTextBoxCell();
                        cellname.Value = "ChkBx:";
                        row.Cells.AddRange(new DataGridViewCell[] { cellname, celltype });
                        break;
                    case CtrlTypes.Txt:
                        row = new DataGridViewRow();
                        celltype = new DataGridViewTextBoxCell();
                        celltype.Value = "Hello World";
                        cellname = new DataGridViewTextBoxCell();
                        cellname.Value = "TxtBx:";
                        row.Cells.AddRange(new DataGridViewCell[] { cellname, celltype });
                        break;
                }
                grid.Rows.Add(row);
            }
        }
    }