B4J Question Update textfield, textarea or label in a loop

Sub SendData
    dim lines() as string = regex.split("/n", ta.text)
    for each line in Lines
        CallSubDelay2(Me, "ExecuteLine", line)
    next
End Sub

Sub ExecuteLine(Line as string)
    'send your line to the serial port
    tfProgress.text = "your progress here"
End Sub

public Sub upload_file(nom_fichier As String,edit As TextArea)
     upload_timer.Initialize("upload_timer_loop", Main.upload_delay)   
     serial.write_com_port_cr("load "&nom_fichier)
    ' init upload list
    upload_list.Initialize
    upload_list.AddAll(Regex.Split(CRLF, edit.text))
    upload_ptr = 0
    Main.upload_progress.Visible = True
    Main.upload_progress.Progress = 0
    upload_timer.Enabled = True
     Log("start upload")

End Sub
' Example:   setProgressBarValue(progressbarMain, 0.90)

Sub upload_timer_loop_tick
    upload_ptr = upload_ptr +1
    If upload_ptr = upload_list.Size Then
          upload_timer.Enabled = False
        serial.write_com_port_cr(Chr(3))
        Main.upload_progress.Visible = False
        Log ("end of upload")       
    Else
        Dim ch As String
        ch = upload_list.Get(upload_ptr)
        serial.write_com_port_cr(ch)       
    End If
   
    Main.t_progress_1.Text =upload_ptr& "/"& upload_list.Size
    Main.upload_progress.Progress = upload_ptr/upload_list.Size
End Sub