CellValuePushed event for Datagridview not fired in C#

Question

I am having DataGridView in a winforms application with a number of ComboBox control. I converted the ComboBox to make it editable.

However, since then, the changes in the column are not being updated in the underlying class object.

When I debug the code, I noticed that the CellValuePushed() event handler was not called when the changes are made in the ComboBox cell.

Any idea what I am missing ?

Thanks

I noticed, when I enter the value in the ComboBox, the CellValueNeeded() eventhandler is being called.

Notice in the screenshot, when I try to enter the data in the combox cell, CellValueNeeded() eventhandler is called

Update :

private void UserDataTable_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
    if ((UserDataTable.CurrentCell.ColumnIndex == 4) ||
                (UserDataTable.CurrentCell.ColumnIndex == 6) ||
                (UserDataTable.CurrentCell.ColumnIndex == 8) ||
                (UserDataTable.CurrentCell.ColumnIndex == 11))
    {
        ComboBox combo = e.Control as ComboBox;    
        combo.DropDownStyle = ComboBoxStyle.DropDown;    
        if (combo == null)
            return;    
    }
}

private void UserDataTable_CellValuePushed(object sender, DataGridViewCellValueEventArgs e)
{
    IntVector temp1 = this.UserData[e.RowIndex];
    switch (e.ColumnIndex)
    {
        case 0: temp1.DeleteMember = (bool)e.Value;
            break;
        case 1:
            temp1.Date1  = Convert.ToDateTime(e.Value).ToString("dd-MM-yy");
            break;
        case 2:
            temp1.CaseNo = Convert.ToString(e.Value);
            break;
        case 3:
            break;
    }
}