用于将数据加载到ListView C＃的启动画面

Question

我创建了一个应用程序，它通过执行存储在SQL Server中的过程将数据加载到ListView中。该过程需要一些时间来执行，当我单击应用程序上的按钮执行该过程时，我的应用程序只是冻结，直到数据加载到ListView中。

当我按下按钮直到数据在列表视图中填充时，如何创建一个加载的启动画面？

我感谢任何反馈。

public async Task<ListView> GetDataAsync()
        {
             var dt = new ListView();
             //var cn = @"Your Connection String";
             //var cmd = @"SELECT * FROM Category";
             //var da = new SqlDataAdapter(cmd, cn);
             SqlConnection conn = new SqlConnection();
             conn.Open();

             SqlCommand cmd = new SqlCommand("[Loyalty_Swipe]", conn);
             cmd.CommandType = CommandType.StoredProcedure;
             cmd.CommandTimeout = 0;
             SqlDataReader reader;

             cmd.Parameters.AddWithValue("@StartDate", txtStartDate.Text);
             cmd.Parameters.AddWithValue("@EndDate", txtEndDate.Text);
             cmd.Parameters.AddWithValue("@CustomerID", txtCustID.Text);
             reader = cmd.ExecuteReader();
             metroListView1.Items.Clear();

             await Task.Run(() =>
             {
                 while (reader.Read())
                 {

                     metroListView1.Columns[0].Text = "Date";
                     metroListView1.Columns[1].Text = "Store Code";
     ListViewItem listview = new   ListViewItem(reader["Date"].ToString());
                     listview.SubItems.Add(reader["StoreCode"].ToString());
                     listview.SubItems.Add(reader["StoreName"].ToString());
                     listview.SubItems.Add(reader["TillNumber"].ToString());
                     listview.SubItems.Add(reader["TranNumber"].ToString());
                     listview.SubItems.Add(reader["Amount"].ToString());
                     listview.SubItems.Add(reader["Discount"].ToString());
                  listview.SubItems.Add(reader["ProcessedFlag"].ToString());
                 listview.SubItems.Add(reader["Processed Date"].ToString());
                 metroListView1.Items.Add(listview);




                 };
             });
             conn.Close();
             pbLoad.Hide();
             btnExport.Enabled = true;
             return dt;
        }