Python Tkinter Call event after every 30 seconds or certain time interval

Question

I am writing a program in which I want to send data to socket after every 30 seconds.

import socket
from Tkinter import *
import tkMessageBox
#from threading import *
import thread

_connect = False
u_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

def conn(IP,PORT):
    try:
        print 'start'

        u_sock.connect((IP, PORT))
        print 'success'
        _connect = True
    except socket.error, (value,message):
        if u_sock:
            print 'fail'
            u_sock.close()
            return
def connFunction():
    IP = IP_entry.get()
    if len(IP) < 7:
        tkMessageBox.showinfo("Error", "Invalid IP Address")
        return
    PORT = int(PORT_entry.get())
    print IP , PORT
    thread.start_new_thread(conn,(IP, PORT, ))
def SEND():
    print 'Send'
    if(_connect == True):
        print 'sending...'
        Inv = 'DATA'
        u_sock.send(Inv.decode('hex'))
        data = u_sock.recv(4096)
        d = data.encode('hex').upper()
        print 'Received', repr(d)


GUI = Tk()
GUI.title('RFID')
#GUI.geometry("365x280")
GUI.wm_iconbitmap('RFID.ico')
GUI.columnconfigure(8, pad=3)


GUI.rowconfigure(8, pad=3)

IP_label = Label(GUI,text = "IP Address: ",borderwidth=5)
IP_label.grid(column=0, row=1, sticky=W)
IP_entry = Entry(GUI,width=15,borderwidth=3)
IP_entry.grid(column=3,row=1,sticky=E)
PORT_label = Label(GUI,text = "Port: ",borderwidth=5)
PORT_label.grid(column=8, row=1, sticky=E)
PORT_entry = Entry(GUI,width=6,borderwidth=3)
PORT_entry.grid(column=9,row=1,sticky=E)

Conn_button= Button(GUI,text="Connect",command=connFunction,borderwidth=1,height=1,width=12)
Conn_button.grid(column=16,row=1,padx=10,pady=5,sticky=(W,E))
#GUI.after(1000,SEND)
GUI.mainloop()

I need to call send function after every 30 seconds or how to create the event which is automatically called after every 30 seconds . I try to do this GUI.after(1000,SEND) but it does not works for me. it calls the SEND function only first time... Kindly Help me out with an example. Thanks

Answer 1

Assuming that SEND takes less than a few hundred milliseconds, remove the threading code and use after. The key is to call after inside the SEND function so that it auto-repeats.

def SEND():
    print 'Send'
    ...
    GUI.after(30000, SEND)

...
GUI = Tk()
...
SEND()
GUI.mainloop()