How to Show Multiple Canvases at the Same Time in Tkinter
Tkinter is a powerful Python GUI module that provides a variety of widgets for creating graphical user interfaces. One of the most popular Tkinter widgets is canvas. The canvas is a powerful and versatile widget that allows you to draw complex graphics and create interactive user interfaces.
However, one limitation of canvas is that it allows you to display only one canvas at a time. This is problematic if you want to display multiple canvases in the same window. Fortunately, there is a relatively simple solution that involves creating multiple canvas objects and using the grid layout manager to display them.
In this article, we will walk through the steps necessary to show multiple canvases at the same time in Tkinter. We will use Python 3.x and assume that you have a basic understanding of Python programming and the Tkinter GUI toolkit.
Creating Multiple Canvas Objects
The first step in displaying multiple canvases is to create multiple canvas objects. This can be done using the Canvas widget constructor. Here is an example of how to create two canvas objects:
from tkinter import *
root = Tk()
canvas1 = Canvas(root, width=200, height=200, bg='white')
canvas2 = Canvas(root, width=200, height=200, bg='white')
canvas1.grid(row=0, column=0)
canvas2.grid(row=0, column=1)
root.mainloop()
In this example, we first import the Tkinter module and create a root window. We then create two canvas objects, canvas1 and canvas2, with a width and height of 200 pixels, and a background color of white. Finally, we use the grid layout manager to display the canvases side by side in the same window.
Adding Graphics to the Canvases
Once you have created multiple canvas objects, you can add graphics to them just like you would with a single canvas. Here is an example of how to add a rectangle to each canvas:
from tkinter import *
root = Tk()
canvas1 = Canvas(root, width=200, height=200, bg='white')
canvas2 = Canvas(root, width=200, height=200, bg='white')
canvas1.grid(row=0, column=0)
canvas2.grid(row=0, column=1)
canvas1.create_rectangle(50, 50, 150, 150, fill='red')
canvas2.create_rectangle(50, 50, 150, 150, fill='blue')
root.mainloop()
In this example, we use the create_rectangle method to add a rectangle to each canvas. We specify the coordinates of the rectangle (50, 50, 150, 150), as well as the fill color (red for canvas1 and blue for canvas2). The result is two rectangles displayed side by side in the same window.
Using a Loop to Create Multiple Canvases
If you need to create a large number of canvases, it is more efficient to use a loop to create canvas objects. Here is an example of how to create ten canvases using a loop:
from tkinter import *
root = Tk()
canvas_list = []
for i in range(10):
canvas = Canvas(root, width=200, height=200, bg='white')
canvas.grid(row=0, column=i)
canvas_list.append(canvas)
root.mainloop()
In this example, we first create an empty list called canvas_list to store the canvas objects. We then use a for loop to create ten canvas objects. Each time through the loop, we create a new canvas object, use the grid layout manager to display it in a new column, and append it to the canvas_list. The result is ten canvases displayed side by side in the same window.
Conclusion
In conclusion, displaying multiple canvases in Tkinter is relatively straightforward once you understand how to create canvas objects and use the grid layout manager. By creating multiple canvas objects and using the grid layout manager to display them side by side, you can create complex graphics and interactive user interfaces that would be difficult to achieve with a single canvas. With the techniques presented in this article, you should be well on your way to creating powerful and versatile GUI applications with Tkinter.