Coding a Simple Python Timer with Tkinter

When I talked to my friend, a professional Python developer, about different ways of coding apps with a GUI and mentioned tkinter, he laughed at me, saying that this framework is too primitive. Sure, for specialists building Django, Flask, and APIs, apps made with tkinter might seem like a school project. However, this is a great solution if you are not a full-stack snob but need a quick yet scalable way to code any GUI app in minutes.

As a Python lover, I enjoy experimenting with coding different things, from statistical analytics to OCR programs that capture text from images.
Recently, I encountered the concept of time tracking in my work and decided to build my own Python timer.

The prototype employee time tracker I drew inspiration from is a powerful solution with servers, databases, multi-layer security, and, of course, a strong development team. So, let’s see what tkinter can do about it.

How to make a timer in Python

First, let's take a look at what the original app timeline looks like:

Now, see what Python timer I created:

There's no advanced functionality, but literally three options:

• Launching time tracking
• Pausing
• Stop timer with log

import time
import tkinter as tk
from tkinter import messagebox

class SimpleTimeTracker:
    def __init__(self, root):
        self.start_time = None
        self.paused_time = 0
        self.running = False
        self.paused = False
        self.update_interval = 1000  # Update every 1000 ms (1 second)
        self.root = root

        # Create GUI components
        self.root.title("Simple Time Tracker")

        self.start_button = tk.Button(self.root, text="Start", command=self.start)
        self.start_button.pack(pady=10)

        self.pause_button = tk.Button(self.root, text="Pause", command=self.pause)
        self.pause_button.pack(pady=10)

        self.stop_button = tk.Button(self.root, text="Stop", command=self.stop)
        self.stop_button.pack(pady=10)

        self.time_label = tk.Label(self.root, text="Elapsed Time: 0.00 seconds")
        self.time_label.pack(pady=10)

        self.timeline_label = tk.Label(self.root, text="Tracked Times:")
        self.timeline_label.pack(pady=10)

        self.timeline_listbox = tk.Listbox(self.root)
        self.timeline_listbox.pack(pady=10, fill=tk.BOTH, expand=True)

    def start(self):
        if not self.running:
            self.start_time = time.time() - self.paused_time
            self.running = True
            self.paused = False
            self.update_timer()
            self.time_label.config(text="Elapsed Time: 0.00 seconds")

    def pause(self):
        if not self.running:
            return

        if self.paused:
            self.start_time = time.time() - self.paused_time
            self.paused = False
            self.update_timer()
        else:
            self.paused_time = time.time() - self.start_time
            self.paused = True

    def stop(self):
        if not self.running:
            messagebox.showerror("Error", "Time tracking has not been started.")
            return

        if self.paused:
            elapsed_time = self.paused_time
        else:
            self.end_time = time.time()
            elapsed_time = self.end_time - self.start_time

        formatted_time = f"Start: {time.ctime(self.start_time)}, End: {time.ctime(time.time())}, Elapsed: {elapsed_time:.2f} seconds"
        self.timeline_listbox.insert(tk.END, formatted_time)

        self.running = False
        self.paused = False

        self.time_label.config(text=f"Elapsed Time: {elapsed_time:.2f} seconds")
        self.paused_time = 0
        self.reset()

    def update_timer(self):
        if self.running and not self.paused:
            elapsed_time = time.time() - self.start_time
            self.time_label.config(text=f"Elapsed Time: {elapsed_time:.2f} seconds")
            self.root.after(self.update_interval, self.update_timer)

    def reset(self):
        self.start_time = None
        self.paused_time = 0

if __name__ == "__main__":
    root = tk.Tk()
    root.geometry("400x400")
    tracker = SimpleTimeTracker(root)
    root.mainloop()

Try this out for yourself. I launched the tracker only in my Jupyter Lab to experiment with it. And yes, the timer I coded was built with the help of ChatGPT. It took me just four prompts to refine it to its current state.

When I started coding about five years ago, I used to spend hours creating anything in tkinter. I have built dozens of simple apps, and now I know how to interact with ChatGPT to get the results I want.

Keep it easy, and never be afraid of experimenting - because Python has no limits!