We are now stepping into making applications with graphical elements, we will learn how to make cool apps and focus more on its GUI(Graphical User Interface) using Tkinter.

Use Cases of Tkinter

• Creating Windows & Dialogs: Easily make windows with labels, buttons, and input boxes using Tk(), Label, Button, Entry, etc.
• Desktop GUI Applications: Build full desktop apps with menus, checkboxes, radio buttons, and use pack() or grid() to arrange them.
• GUI for Command-Line Programs: Add buttons and input fields to replace command-line inputs using Entry, Button, and event handlers.
• Creating Custom Widgets: Inherit from Tkinter's widget classes to define your own widgets with custom behavior and design.
• Quick GUI Prototyping: Quickly test design ideas by creating simple layouts and interactions using basic Tkinter functions.

To understand Tkinter better, we will create a simple GUI. 

Getting Started with Tkinter

1. Import tkinter package and all of its modules.

2. Create a root window. Give the root window a title(using title()) and dimension(using geometry()).  All other widgets will be inside the root window. 

3. Use mainloop() to call the endless loop of the window. If you forget to call this nothing will appear to the user. The window will wait for any user interaction till we close it.

# Import Module
from tkinter import *

# create root window
root = Tk()

# root window title and dimension
root.title("Welcome to GeekForGeeks")
# Set geometry (widthxheight)
root.geometry('350x200')

# all widgets will be here
# Execute Tkinter
root.mainloop()

 Output
 

4. We'll add a label using the Label Class and change its text configuration as desired.  The grid() function is a geometry manager which keeps the label in the desired location inside the window. If no parameters are mentioned by default it will place it in the empty cell; that is 0,0 as that is the first location.  

# Import Module
from tkinter import *

# create root window
root = Tk()

# root window title and dimension
root.title("Welcome to GeekForGeeks")
# Set geometry(widthxheight)
root.geometry('350x200')

#adding a label to the root window
lbl = Label(root, text = "Are you a Geek?")
lbl.grid()

# Execute Tkinter
root.mainloop()

Output
 

5. Now add a button to the root window. Changing the button configurations gives us a lot of options.  In this example we will make the button display a text once it is clicked and also change the color of the text inside the button. 

from tkinter import *

# create root window
root = Tk()

# root window title and dimension
root.title("Welcome to GeekForGeeks")
# Set geometry(widthxheight)
root.geometry('350x200')

# adding a label to the root window
lbl = Label(root, text = "Are you a Geek?")
lbl.grid()

# function to display text when
# button is clicked
def clicked():
    lbl.configure(text = "I just got clicked")

# button widget with red color text
# inside
btn = Button(root, text = "Click me" ,
             fg = "red", command=clicked)
# set Button grid
btn.grid(column=1, row=0)

# Execute Tkinter
root.mainloop()

Output:  
 

6. Using the Entry() class we will create a text box for user input. To display the user input text, we'll make changes to the function clicked(). We can get the user entered text using the get() function. When the Button after entering of the text, a default text concatenated with the user text. Also change button grid location to column 2 as Entry() will be column 1.

# Import Module
from tkinter import *

# create root window
root = Tk()

# root window title and dimension
root.title("Welcome to GeekForGeeks")
# Set geometry(widthxheight)
root.geometry('350x200')

# adding a label to the root window
lbl = Label(root, text = "Are you a Geek?")
lbl.grid()

# adding Entry Field
txt = Entry(root, width=10)
txt.grid(column =1, row =0)


# function to display user text when 
# button is clicked
def clicked():

    res = "You wrote" + txt.get()
    lbl.configure(text = res)

# button widget with red color text inside
btn = Button(root, text = "Click me" ,
             fg = "red", command=clicked)
# Set Button Grid
btn.grid(column=2, row=0)

# Execute Tkinter
root.mainloop()

Output: 

7. To add a menu bar, you can use Menu class. First, we create a menu, then we add our first label, and finally, we assign the menu to our window. We can add menu items under any menu by using add_cascade().

# Import Module
from tkinter import *

# create root window
root = Tk()

# root window title and dimension
root.title("Welcome to GeekForGeeks")
# Set geometry(widthxheight)
root.geometry('350x200')

# adding menu bar in root window
# new item in menu bar labelled as 'New'
# adding more items in the menu bar 
menu = Menu(root)
item = Menu(menu)
item.add_command(label='New')
menu.add_cascade(label='File', menu=item)
root.config(menu=menu)

# adding a label to the root window
lbl = Label(root, text = "Are you a Geek?")
lbl.grid()

# adding Entry Field
txt = Entry(root, width=10)
txt.grid(column =1, row =0)


# function to display user text when
# button is clicked
def clicked():

    res = "You wrote" + txt.get()
    lbl.configure(text = res)

# button widget with red color text inside
btn = Button(root, text = "Click me" ,
             fg = "red", command=clicked)
# Set Button Grid
btn.grid(column=2, row=0)

# Execute Tkinter
root.mainloop()

Output
This simple GUI covers the basics of Tkinter package. Similarly, you can add more widgets and change their configurations as desired.  

Tkinter Widgets 

Tkinter is the GUI library of Python, it provides various controls, such as buttons, labels and text boxes used in a GUI application. These controls are commonly called Widgets.  The list of commonly used Widgets are mentioned below - 

Geometry Management 

All Tkinter widgets have access to specific geometry management methods, which have the purpose of organizing widgets throughout the parent widget area. Tkinter exposes the following geometry manager classes: pack, grid, and place. Their description is mentioned below - 

In this article, we have learned about GUI programming in Python and how to make GUI in Python. GUI is a very demanded skill so you must know how to develop GUI using Python. Hope this article helped you in creating GUI using Python.

Tkinter Alternatives

There are several libraries that are similar to Tkinter and can be used for creating graphical user interfaces (GUIs) in Python. Some examples include:

1. PyQt: PyQt is a GUI library that allows you to create GUI applications using the Qt framework. It is a comprehensive library with a large number of widgets and features.
2. wxPython: wxPython is a library that allows you to create GUI applications using the wxWidgets framework. It includes a wide range of widgets in it's GUI toolkit and is cross-platform, meaning it can run on multiple operating systems.
3. PyGTK: PyGTK is a GUI library that allows you to create GUI applications using the GTK+ framework. It is a cross-platform library with a wide range of widgets and features.
4. Kivy: Kivy is a library that allows you to create GUI applications using a modern, responsive design. It is particularly well-suited for building mobile apps and games.
5. PyForms: PyForms is a library that allows you to create GUI applications using a simple, declarative syntax. It is designed to be easy to use and has a small footprint.
6. Pygame: PyForms is a library that is popular because you can develop video games using it. It is a free, open source, and cross-platform wrapper for the Simple DirectMedia Library (SDL). You can check Pygame Tutorial if you are interested in video game development.

Check Sample Code: Simple GUI calculator using Tkinter

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• Python | Simple GUI calculator using Tkinter