How to Create a GUI in Python using Tkinter

Looking to create a Graphical User Interface (GUI) in Python using tkinter?

If so, in this tutorial, I’ll show you how to create a tkinter GUI with the following components:

  • Canvas screen, where you can place items, such as labels and buttons
  • Labels to display text on top of the Canvas
  • Entry Boxes to allow users type values
  • Functions to display Bar and Pie charts
  • Buttons to trigger the functions and exit the application

By the end of this tutorial, you’ll be able to create the following GUI:

How to Create a GUI in Python using Tkinter

Create a GUI in Python using tkinter

To start, I’ll share the complete code that you can paste into Python in order to create the above tkinter GUI. I’ll then explain the main parts of the code.

You’ll need to make sure that the matplotlib package is installed in python. This package is used to display the charts (i.e., bar and pie charts).

import tkinter as tk
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from matplotlib.figure import Figure
 
root= tk.Tk()
  
canvas1 = tk.Canvas(root, width = 800, height = 300)
canvas1.pack()

label1 = tk.Label(root, text='Graphical User Interface')
label1.config(font=('Arial', 20))
canvas1.create_window(400, 50, window=label1)
   
entry1 = tk.Entry (root)
canvas1.create_window(400, 100, window=entry1) 
  
entry2 = tk.Entry (root)
canvas1.create_window(400, 120, window=entry2) 
          
entry3 = tk.Entry (root)
canvas1.create_window(400, 140, window=entry3) 
  
def create_charts():
    global x1
    global x2
    global x3
    global bar1
    global pie2
    x1 = float(entry1.get())
    x2 = float(entry2.get())
    x3 = float(entry3.get())

    figure1 = Figure(figsize=(4,3), dpi=100) 
    subplot1 = figure1.add_subplot(111) 
    xAxis = [float(x1),float(x2),float(x3)] 
    yAxis = [float(x1),float(x2),float(x3)] 
    subplot1.bar(xAxis,yAxis, color = 'lightsteelblue') 
    bar1 = FigureCanvasTkAgg(figure1, root) 
    bar1.get_tk_widget().pack(side=tk.LEFT, fill=tk.BOTH, expand=0)
      
    figure2 = Figure(figsize=(4,3), dpi=100) 
    subplot2 = figure2.add_subplot(111) 
    labels2 = 'Label1', 'Label2', 'Label3' 
    pieSizes = [float(x1),float(x2),float(x3)]
    my_colors2 = ['lightblue','lightsteelblue','silver']
    explode2 = (0, 0.1, 0)  
    subplot2.pie(pieSizes, colors=my_colors2, explode=explode2, labels=labels2, autopct='%1.1f%%', shadow=True, startangle=90) 
    subplot2.axis('equal')  
    pie2 = FigureCanvasTkAgg(figure2, root)
    pie2.get_tk_widget().pack()

def clear_charts():
    bar1.get_tk_widget().pack_forget()
    pie2.get_tk_widget().pack_forget()
            
button1 = tk.Button (root, text=' Create Charts ',command=create_charts, bg='palegreen2', font=('Arial', 11, 'bold')) 
canvas1.create_window(400, 180, window=button1)

button2 = tk.Button (root, text='  Clear Charts  ', command=clear_charts, bg='lightskyblue2', font=('Arial', 11, 'bold'))
canvas1.create_window(400, 220, window=button2)

button3 = tk.Button (root, text='Exit Application', command=root.destroy, bg='lightsteelblue2', font=('Arial', 11, 'bold'))
canvas1.create_window(400, 260, window=button3)
 
root.mainloop()

Let’s now dive into the main components of the Python code:

The Canvas

The Canvas is your GUI screen in which you can place items, such as buttons, labels, entry boxes and more. You can control the dimensions of the Canvas by changing the width and height values.

canvas1 = tk.Canvas(root, width = 800, height = 300)
canvas1.pack()

The Label

Labels can be used to print text on top of the Canvas. Here, a label was added to display the following text:

‘Graphical User Interface’

You may specify a different font-family and font-size for your label. In our case, the font family is ‘Arial’ and the font size is ’20.’

Finally, you can control the position of the label by modifying the coordinates on the last row below (for our example, the coordinates are 400 and 50):

label1 = tk.Label(root, text='Graphical User Interface')
label1.config(font=('Arial', 20))
canvas1.create_window(400, 50, window=label1)

The Entry Boxes

The 3 entry boxes are used to collect information from the user. That information will then be used to create the matplotlib charts.

As before, you can control the position of the entry boxes by specifying the coordinates.

entry1 = tk.Entry (root)
canvas1.create_window(400, 100, window=entry1) 
  
entry2 = tk.Entry (root)
canvas1.create_window(400, 120, window=entry2) 
          
entry3 = tk.Entry (root)
canvas1.create_window(400, 140, window=entry3)

The Functions

The ‘create_charts‘ function will be called when the user clicks on the first button (i.e., ‘button1’) to draw the charts.

The information collected in the entry boxes, will then be used to depict the bar and pie charts. Here is a full guide that explains how to place charts on a tkinter GUI.

def create_charts():
    global x1
    global x2
    global x3
    global bar1
    global pie2
    x1 = float(entry1.get())
    x2 = float(entry2.get())
    x3 = float(entry3.get())

    figure1 = Figure(figsize=(4,3), dpi=100) 
    subplot1 = figure1.add_subplot(111) 
    xAxis = [float(x1),float(x2),float(x3)] 
    yAxis = [float(x1),float(x2),float(x3)] 
    subplot1.bar(xAxis,yAxis, color = 'lightsteelblue') 
    bar1 = FigureCanvasTkAgg(figure1, root) 
    bar1.get_tk_widget().pack(side=tk.LEFT, fill=tk.BOTH, expand=0)
      
    figure2 = Figure(figsize=(4,3), dpi=100) 
    subplot2 = figure2.add_subplot(111) 
    labels2 = 'Label1', 'Label2', 'Label3' 
    pieSizes = [float(x1),float(x2),float(x3)]
    my_colors2 = ['lightblue','lightsteelblue','silver']
    explode2 = (0, 0.1, 0)  
    subplot2.pie(pieSizes, colors=my_colors2, explode=explode2, labels=labels2, autopct='%1.1f%%', shadow=True, startangle=90) 
    subplot2.axis('equal')  
    pie2 = FigureCanvasTkAgg(figure2, root)
    pie2.get_tk_widget().pack()

The ‘clear_charts‘ function will be called when the user clicks on the second button (i.e., ‘button2’) to clear the charts from the GUI:

def clear_charts():
    bar1.get_tk_widget().pack_forget()
    pie2.get_tk_widget().pack_forget()

The Buttons

The first button (i.e., ‘button1’) can be used to trigger the ‘create_charts‘ function in order to draw the charts.

You can position the button on the Canvas by specifying the coordinates (in our case, the coordinates are 400 and 180):

button1 = tk.Button (root, text=' Create Charts ',command=create_charts, bg='palegreen2', font=('Arial', 11, 'bold')) 
canvas1.create_window(400, 180, window=button1)

The second button (i.e., ‘button2’) triggers the ‘clear_charts‘ function to remove the previous charts from the GUI:

button2 = tk.Button (root, text='  Clear Charts  ', command=clear_charts, bg='lightskyblue2', font=('Arial', 11, 'bold'))
canvas1.create_window(400, 220, window=button2)

The exit application button (i.e., ‘button3’) triggers the ‘destroy’ command to close the tkinter GUI upon a click:

button3 = tk.Button (root, text='Exit Application', command=root.destroy, bg='lightsteelblue2', font=('Arial', 11, 'bold'))
canvas1.create_window(400, 260, window=button3)

Launch the tkinter GUI

Once you’re ready, run the complete code in Python, and you’ll see this initial screen:

How to Create a GUI in Python using Tkinter

Type a value within each of the input boxes. For example, type the values of 4, 5 and 6 in the input boxes:

Then, click on the “Create Charts” button:

Buttons on an interface

You’ll now see the two charts at the bottom section of your screen (based on the 3 values that you typed):

  • On the left side, you’ll see the bar chart
  • On the right side, you’ll observe the pie chart (representing your values in % terms)

GUI in Python using Tkinter

Additional Sources