Hosting custom user control in a DataGridView

Hi,

I have read the article "How to: Host Controls in Windows Forms DataGridView Cells "

, and I don't find how to host my own user control in a DataGridView.

I took the above example and changed the base class from DateTimePicker to CheckBoxUserControl in the class CalendarEditingControl.(I also changed all DateTime type to string).

CheckBoxUserControl contains a few  common standard checkbox controls that can be represented as one string value.

What I want is that in edit mode, my control will show up (like the calendar).

but it doesn't, can someone give a hand here

here is my modified module:

using System;
using System.Windows.Forms;

namespace CheckBox_Custom_Cell
{
    public class CheckBoxColumn : DataGridViewColumn
    {
        public CheckBoxColumn()
            : base(new CheckBoxCell())
        {
        }

        public override DataGridViewCell CellTemplate
        {
            get
            {
                return base.CellTemplate;
            }
            set
            {
                if (value != null &&
                    !value.GetType().IsAssignableFrom(typeof(CheckBoxCell)))
                {
                    throw new InvalidCastException("Must be a CheckBoxCell");
                }
                base.CellTemplate = value;
            }
        }
    }

    public class CheckBoxCell : DataGridViewTextBoxCell
    {

        public CheckBoxCell()
            : base()
        {
        }

        public override void InitializeEditingControl(int rowIndex, object
            initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
        {
            base.InitializeEditingControl(rowIndex, initialFormattedValue,
                dataGridViewCellStyle);
            CheckBoxEditingControl ctl =
                DataGridView.EditingControl as CheckBoxEditingControl;
            ctl.Value = this.Value.ToString();
        }

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

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

        public override object DefaultNewRowValue
        {
            get
            {
                return "Init";
            }
        }
    }

    class CheckBoxEditingControl : CheckBoxUserControl, IDataGridViewEditingControl
    {
        DataGridView dataGridView;
        private bool valueChanged = false;
        int rowIndex;

        public CheckBoxEditingControl()
        {
        }

        public object EditingControlFormattedValue
        {
            get
            {
                return this.Value;
            }
            set
            {
                String newValue = value as String;
                if (newValue != null)
                {
                    this.Value = newValue;
                }
            }
        }

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

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

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

        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 false;
            }
        }

        public void PrepareEditingControlForEdit(bool selectAll)
        {
            // No preparation needs to be done.
        }

        public bool RepositionEditingControlOnValueChange
        {
            get
            {
                return false;
            }
        }

        public DataGridView EditingControlDataGridView
        {
            get
            {
                return dataGridView;
            }
            set
            {
                dataGridView = value;
            }
        }

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

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

        protected override void checkedListBox1_SelectedValueChanged(object sender, EventArgs e)
        {
            // Notify the DataGridView that the contents of the cell
            // have changed.
            valueChanged = true;
            this.EditingControlDataGridView.NotifyCurrentCellDirty(true);
            base.checkedListBox1_SelectedValueChanged(sender, e);
        }
    }

}