CanvasDemo.py

from tkinter import * # Import tkinter
    
class CanvasDemo:
    def __init__(self):
        window = Tk() # Create a window
        window.title("Canvas Demo") # Set title
        
        # Place self.canvas in the window
        self.canvas = Canvas(window, width = 200, height = 100, 
            bg = "white")
        self.canvas.pack()
        
        # Place buttons in frame
        frame = Frame(window)
        frame.pack()
        btRectangle = Button(frame, text = "Rectangle", 
            command = self.displayRect)
        btOval = Button(frame, text = "Oval", 
            command = self.displayOval)
        btArc = Button(frame, text = "Arc", 
            command = self.displayArc)
        btPolygon = Button(frame, text = "Polygon", 
            command = self.displayPolygon)
        btLine = Button(frame, text = "Line", 
            command = self.displayLine)
        btString = Button(frame, text = "String", 
            command = self.displayString)
        btClear = Button(frame, text = "Clear", 
            command = self.clearCanvas)
        btRectangle.grid(row = 1, column = 1)
        btOval.grid(row = 1, column = 2)
        btArc.grid(row = 1, column = 3)
        btPolygon.grid(row = 1, column = 4)
        btLine.grid(row = 1, column = 5)
        btString.grid(row = 1, column = 6)
        btClear.grid(row = 1, column = 7)
        
        window.mainloop() # Create an event loop

    # Display a rectangle
    def displayRect(self):
        self.canvas.create_rectangle(10, 10, 190, 90, tags = "rect")
        
    # Display an oval
    def displayOval(self):
        self.canvas.create_oval(10, 10, 190, 90, fill = "red", 
            tags = "oval")
    
    # Display an arc
    def displayArc(self):
        self.canvas.create_arc(10, 10, 190, 90, start = 0, 
            extent = 90, width = 8, fill = "red", tags = "arc")
    
    # Display a polygon
    def displayPolygon(self):
        self.canvas.create_polygon(10, 10, 190, 90, 30, 50, 
            tags = "polygon")
    
    # Display a line
    def displayLine(self):
        self.canvas.create_line(10, 10, 190, 90, fill = "red", 
            tags = "line")
        self.canvas.create_line(10, 90, 190, 10, width = 9, 
            arrow = "last", activefill = "blue", tags = "line")
    
    # Display a string
    def displayString(self):
        self.canvas.create_text(60, 40, text = "Hi, I am a string", 
           font = "Times 10 bold underline", tags = "string")
    
    # Clear drawings
    def clearCanvas(self):
        self.canvas.delete("rect", "oval", "arc", "polygon", 
            "line", "string")

CanvasDemo() # Create GUI