Python - Project - Pomodoro (Day 28)

This is a 100 Days challenge to learn a new language (Python). 100 Days of Code - The Complete Python Pro Bootcamp 

I will post some notes to motivate myself to finish this challenge.

Goal

Use Tkinter to build a Pomodoro GUI program.

How to add images to Tkinter?

We can use canvas as a wrapper to wrap the components such as image, line, or text.

Ex: 

import tkinter as tk

# Init

root = tk.Tk()

root.title("Exp")

# Init Canvas

canvas = tk.Canvas(width=200, height=224)

tomato_img = tk.PhotoImage(file="tomato.png")

# Create an image to canvas

canvas.create_image(

    100,

    112,

    image=tomato_img,

)

canvas.pack()

# Start the Event Loop

root.mainloop()

How to schedule/cancel a task on Tkinter? 

Reference

after()

* It calls the callback function once after a delay milliseconds.

after_cancel()

* It can stop the particular scheduled task.

Ex:

import tkinter as tk

# Global Variables

scheduled_job_identifier = None

def update_label():

    """Update Lable"""

    label.config(text="Label has been updated!!", fg="blue")

def schedule():

    """Start a scheduled job with 5 seconds delay"""

    global scheduled_job_identifier

    # Update label after 5 seconds delay

    scheduled_job_identifier = root.after(5000, update_label)

def cancel():

    """Cancel the scheduled job"""

    # Terminate the scheduled job

    root.after_cancel(scheduled_job_identifier)

# Init

root = tk.Tk()

root.title("Exp")

root.minsize(width=300, height=100)

# Init Label

label = tk.Label(text="Hello World", fg="red")

label.pack()

# Init Buttons

btn_schedule = tk.Button(

    text="Schedule a task to change label text after 5 seconds",

command=schedule

)

btn_schedule.pack()

btn_cancel = tk.Button(text="cancel", command=cancel)

btn_cancel.pack()

# Start the Event Loop

root.mainloop()

Dynamic Typing

Reference

Dynamic typing means that the type of the variable is determined only during runtime.

Ex: 

value = 1

print(type(value))

value = "Hello World"

print(type(value))

Result:

<class 'int'> <class 'str'>

Project - Pomodoro

Ex:

import tkinter as tk

import math

# Constants

PINK = "#e2979c"

RED = "#e7305b"

GREEN = "#9bdeac"

YELLOW = "#f7f5dd"

FONT_NAME = "Courier"

WORK_MIN = 25

SHORT_BREAK_MIN = 5

LONG_BREAK_MIN = 20

# Global Variables

timer = None

# step 1: Work

# step 2: Short Break

# step 3: Work

# step 4: Short Break

# step 5: Work

# step 6: Short Break

# step 7: Work

# step 8: Long Break

step = 0

def reset_timer():

    """Reset App"""

    ## Cancel timer

    root.after_cancel(timer)

    ## Reset Title

    title_label.config(text="Timer")

    ## Reset countdown text

    canvas.itemconfig(count_down_text, text="00:00")

    ## Reset Marks

    marks_label.config(text="")

    ## Reset steps

    global step

    step = 0

def start_timer():

    """Trigger Count Down function"""

    global step

    step += 1

    if step % 8 == 0:

        # Long Break

        count_down(LONG_BREAK_MIN * 60)

        title_label.config(text="Break", fg=RED)

    elif step % 2 == 0:

        # Short Break

        count_down(SHORT_BREAK_MIN * 60)

        title_label.config(text="Break", fg=PINK)

    else:

        # Work

        count_down(WORK_MIN * 60)

        title_label.config(text="Work", fg=GREEN)

def get_count_down_text(counter):

    """Format count down secongs to readable text"""

    counter_min = math.floor(counter / 60)

    counter_second = counter % 60

    # Dynamic Typing

    if counter_second < 10:

        counter_second = "0" + str(counter_second)

    return f"{counter_min}:{counter_second}"

def count_down(counter):

    """Trigger root after function"""

    canvas.itemconfig(count_down_text, text=get_count_down_text(counter))

    if counter > 0:

        global timer

        timer = root.after(1000, count_down, counter - 1)

    else:

        # Go to next step

        start_timer()

        # Update marks label

        marks = ""

        for _ in range(math.floor(step / 2)):

            marks = marks + "✓"

        marks_label.config(text=marks)

# Init

root = tk.Tk()

root.title("Pomodoro")

root.configure(padx=100, pady=50, bg=YELLOW)

# Init Title Lable

title_label = tk.Label(

    text="Timer", background=YELLOW, foreground=GREEN,

font=(FONT_NAME, 30, "bold")

)

title_label.grid(column=1, row=0)

# Init Canvas

canvas = tk.Canvas(width=200, height=224, background=YELLOW,

highlightthickness=0)

tomato_img = tk.PhotoImage(file="tomato.png")

canvas.create_image(

    100,

    112,

    image=tomato_img,

)

count_down_text = canvas.create_text(

    100, 130, text="00:00", fill="white", font=(FONT_NAME, 35, "bold")

)

canvas.grid(column=1, row=1)

# Init Buttons

start_btn = tk.Button(text="Start", command=start_timer)

start_btn.grid(column=0, row=2)

reset_btn = tk.Button(text="Reset", command=reset_timer)

reset_btn.grid(column=2, row=2)

# Init Marks Label

marks_label = tk.Label(

    text="", background=YELLOW, foreground=GREEN,

font=(FONT_NAME, 10, "bold")

)

marks_label.grid(column=1, row=3)

# Start the Event Loop

root.mainloop()