I Want To Run And Kill A Thread On A Button Press

I have a program that is supposed to send a few data points over a serial connection to an arduino which will control some motors to move. I can send the control signals individual

Solution 1:

Question: run and kill a thread on a button press

There is no such a thing called .kill(.... Start making your def send_file(... a Thread object which is waiting your commands.

Note: As it stands, your inner while isready == 1: will not stop by using m.set_state('stop'). It's mandatory to start the Thread object inside:

if __name__ == '__main__':
    m = MotorControl()

import threading, time

classMotorControl(threading.Thread):
    def__init__(self):
        super().__init__()
        self.state = {'is_alive'}
        self.start()

    defset_state(self, state):
        if state == 'stop':
            state = 'idle'

        self.state.add(state)

    defterminate(self):
        self.state = {}

    # main function in a Thread objectdefrun(self):
        # Here goes your initalisation# ...while'is_alive'in self.state:

            if'start'in self.state:
                isready = 1while isready == 1:
                    # Here goes your activity# Simulate activityprint('running')
                    time.sleep(2)
                    isready = 0

                self.state = self.state - {'start'}
                self.state.add('idle')

            elif'idle'in self.state:
                print('idle')
                time.sleep(1)

if __name__ == '__main__':
    m = MotorControl()

    time.sleep(2)
    m.set_state('start')
    time.sleep(3)
    m.set_state('stop')
    time.sleep(3)
    m.set_state('start')

    time.sleep(4)
    m.terminate()
    print('EXIT __main__')

---

Your tk.Button should look like:

tk.Button(text = "Run File", command = lambda:m.set_state('start'))
tk.Button(text = "Stop File", command = lambda:m.set_state('stop'))
tk.Button(text = "Terminate", command = m.terminate)

Solution 2:

The answer I have gone with is simple due to my simple understanding of threading and unique circumstances with which I am using the threading. Instead of terminating the thread in a way I was hoping, I added another conditional statement to the sending line of the send_file function.

while isready == 1:
        for i inrange(len(pos1)):
            if motorstop == False:
                print("Step: " + str(i+1))
                #data = struct.pack('!llllhhhhhhhh', pos1[i], pos2[i], pos3[i], pos4[i], speed1[i], speed2[i], speed3[i], speed[4], accel1[i], accel2[i], accel3[i], accel4[i])
                data = struct.pack("!llhhhh", pos1[i], pos2[i], speed1[i], speed2[i], accel1[i], accel2[i])
                ser.write(data)
            else:
                isready = 0break

and I have updated my stop() func to the following:

defstop():
    try:
        global motorstop
        global t
        motorstop = True
        t.join()
    except:
        print("Error: thread wasn't killed")

I'm not exactly sure how it works but it is much simpler than what was mentioned by @stovefl.

With this code, since the function is mostly just sleeping, it can run but it won't send any new information and then will .join() after the next iteration.