鼠标点击datagridview上的checkbox 没反应。请问是怎么回事呢？
我的代码如下：

public void DtToView(DataTable calldt)
{
dataGridViewX1.Rows.Clear();
dataGridViewX1.Columns.Clear();
dataGridViewX1.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.DisplayedCellsExceptHeaders;
dataGridViewX1.ReadOnly = true;
dataGridViewX1.ColumnCount = 5;
dataGridViewX1.ColumnHeadersVisible = true;

        // Set the column header style.
        DataGridViewCellStyle columnHeaderStyle = new DataGridViewCellStyle();

        columnHeaderStyle.BackColor = Color.DarkSlateGray;
        columnHeaderStyle.Font = new Font("Verdana", 10, FontStyle.Regular);
        dataGridViewX1.ColumnHeadersDefaultCellStyle = columnHeaderStyle;

        //datagridview上新建添加的checkbox控件
        DataGridViewCheckBoxColumn ck = new DataGridViewCheckBoxColumn();
        //ck.TrueValue = true;
        //ck.FalseValue = false;
        dataGridViewX1.Columns.Insert(0, ck);
        // Set the column header names.
        dataGridViewX1.Columns[0].Name = "选择";
        dataGridViewX1.Columns[1].Name = "id";
        dataGridViewX1.Columns[2].Name = "callid";
        dataGridViewX1.Columns[3].Name = "姓名";
        dataGridViewX1.Columns[4].Name = "电话";
        dataGridViewX1.Columns[5].Name = "状态";

        dataGridViewX1.Columns[0].Width = 45;
        dataGridViewX1.Columns[1].Visible = false;
        dataGridViewX1.Columns[2].Visible = false;
        dataGridViewX1.Columns[3].Width = 75;
        dataGridViewX1.Columns[4].Width = 100;
        dataGridViewX1.Columns[5].Width = 65;
        dataGridViewX1.RowsDefaultCellStyle.Font = new Font("宋体", 10, FontStyle.Regular);
        for (int i = 0; i < calldt.Rows.Count; i++)
        {
            int index = this.dataGridViewX1.Rows.Add();
            this.dataGridViewX1.Rows[index].Cells[1].Value = calldt.Rows[i][0].ToString();
            this.dataGridViewX1.Rows[index].Cells[2].Value = calldt.Rows[i][1].ToString();
            this.dataGridViewX1.Rows[index].Cells[3].Value = calldt.Rows[i][2].ToString();
            this.dataGridViewX1.Rows[index].Cells[4].Value = calldt.Rows[i][3].ToString();
            string status = calldt.Rows[i][4].ToString();
            if (int.Parse(status) == 1)
            {
                //dataGridViewX1.Columns[0].ReadOnly = false; 
                this.dataGridViewX1.Rows[index].Cells[5].Value = "已分发";
            }
            else if (int.Parse(status) == 0)
            {
                //dataGridViewX1.Columns[0].ReadOnly = false;
                this.dataGridViewX1.Rows[index].Cells[5].Value = "未分发";
            }
        }
    }