Automatically change values of on a canvas tkinter every second-CodePudding

I am building a simple program that gets date and time. I am able to get the values alright, but i am unable to update the values in the canvas. Here is my function that gets the temperature.

from time import strftime
def my_time():
    time_string = strftime('%H:%M:%S %p') # time format
    return time_string

time = my_time()

canvas.create_text(
    1068.0,
    744.0,
    anchor="nw",
    text=time,
    fill="#FFFFFF",
    font=("Poppins Bold", 120 * -1)
)

window.resizable(False, False)
window.mainloop()

I followed this tutorial, but i am not using the labels they used. I want to use the canvas.create_text. https://www.plus2net.com/python/tkinter-clock.php

How do i make sure the time automatically updates every second? I have tried threading, i have tried .after(1000, functionName) but still. I am new to python so kindly be lenient with the answer.

In my code, i have a separate function for getting the temperature from a sensor, I am able to get the temperature, but i need to update that every second too. But i believe if i am able to do it for the time, i can get it for the temperature too.

Here is the code for getting the temperature.

def read_temp_raw():
    with open(device_path  '/w1_slave','r') as f:
        valid, temp = f.readlines()
    return valid, temp

def read_temp():
    global c
    valid, temp = read_temp_raw()

    while 'YES' not in valid:
        time.sleep(0.2)
        valid, temp = read_temp_raw()

    pos = temp.index('t=')
    if pos != -1:
        #read the temperature .
        temp_string = temp[pos 2:]
        temp_c = float(temp_string)/1000.0
        temp_c = round(temp_c, 2)
        temp_f = temp_c * (9.0 / 5.0)   32.0
        temp_f = round(temp_f, 2)
        return temp_c, temp_f

c, f = read_temp()


canvas.create_text(
    696.0,
    127.0,
    anchor="nw",
    text=c,
    fill="#FFFFFF",
    font=("Poppins Bold", 309 * -1)
)

CodePudding user response：

The ID of the text object is returned by create_text. Save it and use it to change the text with canvas.itemconfig:

def update_temp():
    c, _ = read_temp()
    canvas.itemconfig(temp_text_id, text=str(c))
    canvas.after(1000, update_time)

c, f = read_temp()

temp_text_id = canvas.create_text(
    1068.0,
    744.0,
    anchor="nw",
    text=str(c),
    fill="#FFFFFF",
    font=("Poppins Bold", 120 * -1)
)
canvas.after(1000, update_temp)
window.mainloop()