Creating a colorful canvas drawing program with Python and Tkinter

Python Tkinter Canvas and Graphics: Exercise-8 with Solution

Write a Python program that allows the user to select a color and draw on the Canvas with that color using Tkinter.

Sample Solution:

Python Code:

import tkinter as tk
from tkinter import colorchooser

def choose_color():
    color = colorchooser.askcolor()[1]
    if color:
        current_color.set(color)

def start_drawing(event):
    global last_x, last_y, drawing
    last_x, last_y = event.x, event.y
    drawing = True

def draw(event):
    global last_x, last_y
    if drawing:
        x, y = event.x, event.y
        canvas.create_line(last_x, last_y, x, y, fill=current_color.get(), width=2)
        last_x, last_y = x, y

def stop_drawing(event):
    global drawing
    drawing = False

root = tk.Tk()
root.title("Colorful Canvas")

canvas = tk.Canvas(root, bg="white")
canvas.pack(fill=tk.BOTH, expand=True)

current_color = tk.StringVar()
current_color.set("black")

color_button = tk.Button(root, text="Choose Color", command=choose_color)
color_button.pack()

drawing = False  # Initialize the drawing state variable

canvas.bind("<Button-1>", start_drawing)
canvas.bind("<B1-Motion>", draw)
canvas.bind("<ButtonRelease-1>", stop_drawing)

root.mainloop()

Explanation:

In the exercise above -

• First we create a "Canvas" widget where the user can draw.
• There is a "Choose Color" button that opens a color chooser dialog when clicked. The chosen color is stored in the 'current_color' variable.
• We use the "bind()" method to capture mouse events for starting, drawing, and stopping the drawing process. When the user clicks and drags the mouse, it draws lines on the canvas using the selected color.
• The color is set dynamically as per the user's choice from the color chooser dialog.
• Now using the selected color, the user can draw on the canvas.

Output:

Flowchart:

Python Code Editor:

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