How can I display the current time left in a timer in a label?

Question

I made a timer for part of a project I am making. I have the timer made, but I would like for the time left in the timer to be printed on to a label. ALso, if this wasn't expected, I would like for the time to be on the label then after a second it deletes itself and places the new time remaining(I do not want it to keep printing the time on a new line one after another).

One post I found that was pretty much what I wanted to do, but it did not work for me and I had to change some functions and add some new ones. I am not sure why this didn't work, but I would prefer it to be different because it has a preset time of 10 seconds and I would like for it to be the users choice. The link: Making a countdown timer with Python and Tkinter?

class Application(Frame):
    def createWidgets(self):

        # More code here    

        self.timeLeftLabel = Label(root, text='Time Left: ')
        self.timeLeftLabel.pack()

def timeLeft(t):
    time.sleep(1)
    print(t)

def countdownInGUI():
    countdown = Label(root, text=entryInt)
    countdown.pack()

entryInt = IntVar()
t = Entry(root, textvariable=entryInt)
t.bind('<Return>', get)
t.pack(pady=5)

I am hoping that the time left will show in the label called countdown, but instead nothing shows up until the timer ends then it says "PY_VAR0" on a new line for each second (So its on 3 lines for 3 seconds, 4 lines for seconds, etc..)

Answer 1

In your func countdownInGUI, you created your Label widget by Label(root, text=entryInt), so tkinter will try to convert what you passed to a string. What you should do is to set entryInt as a textvariable instead.

On the other hand, you don't really need to set a textvariable for your Entry widget - you can retrieve the content directly by calling Entry.get().

Here is how everything could work base on your code:

import tkinter as tk

class Application(tk.Frame):
    def __init__(self,master=None,**kwargs):
        super().__init__(master,**kwargs)
        self.master = master
        self.timeLeftLabel = tk.Label(master, text='Time Left: ')
        self.timeLeftLabel.pack()
        self.entryInt = tk.StringVar()
        self.countdown = tk.Label(master, textvariable=self.entryInt)
        self.countdown.pack()
        self.t = tk.Entry(master)
        self.t.bind('<Return>', self.start_countdown)
        self.t.pack(pady=5)

    def start_countdown(self,event=None):
        if self.t.get().isdigit():
            self.time_left(int(self.t.get()))

    def time_left(self, t):
        self.entryInt.set(t)
        t-=1
        if t>=0:
            self.master.after(1000,self.time_left, t)
        else:
            self.entryInt.set("Boom!")

root = tk.Tk()

frame = Application(root)
frame.pack()

root.mainloop()