Introduction to Tkinter

Graphical User Interface(GUI) is a form of user interface which allows users to interact with computers through visual indicators using items such as icons, menus, windows, etc. It has advantages over the Command Line Interface(CLI) where users interact with computers by writing commands using keyboard only and whose usage is more difficult than GUI.

What is Tkinter?

Tkinter is the inbuilt python module that is used to create GUI applications. It is one of the most commonly used modules for creating GUI applications in Python as it is simple and easy to work with. You don’t need to worry about the installation of the Tkinter module separately as it comes with Python already. It gives an object-oriented interface to the Tk GUI toolkit.
Some other Python Libraries available for creating our own GUI applications are

Kivy
Python Qt
wxPython

Among all Tkinter is most widely used

Here are some common use cases for Tkinter:

Creating windows and dialog boxes: Tkinter can be used to create windows and dialog boxes that allow users to interact with your program. These can be used to display information, gather input, or present options to the user.
Building a GUI for a desktop application: Tkinter can be used to create the interface for a desktop application, including buttons, menus, and other interactive elements.
Adding a GUI to a command-line program: Tkinter can be used to add a GUI to a command-line program, making it easier for users to interact with the program and input arguments.
Creating custom widgets: Tkinter includes a variety of built-in widgets, such as buttons, labels, and text boxes, but it also allows you to create your own custom widgets.
Prototyping a GUI: Tkinter can be used to quickly prototype a GUI, allowing you to test and iterate on different design ideas before committing to a final implementation.

In summary, Tkinter is a useful tool for creating a wide variety of graphical user interfaces, including windows, dialog boxes, and custom widgets. It is particularly well-suited for building desktop applications and adding a GUI to command-line programs.

What are Widgets?

Widgets in Tkinter are the elements of GUI application which provides various controls (such as Labels, Buttons, ComboBoxes, CheckBoxes, MenuBars, RadioButtons and many more) to users to interact with the application. Fundamental structure of tkinter program

Basic Tkinter Widgets:

Widgets	Description
Label	It is used to display text or image on the screen
Button	It is used to add buttons to your application
Canvas	It is used to draw pictures and others layouts like texts, graphics etc.
ComboBox	It contains a down arrow to select from list of available options
CheckButton	It displays a number of options to the user as toggle buttons from which user can select any number of options.
RadioButton	It is used to implement one-of-many selection as it allows only one option to be selected
Entry	It is used to input single line text entry from user
Frame	It is used as container to hold and organize the widgets
Message	It works same as that of label and refers to multi-line and non-editable text
Scale	It is used to provide a graphical slider which allows to select any value from that scale
Scrollbar	It is used to scroll down the contents. It provides a slide controller.
SpinBox	It is allows user to select from given set of values
Text	It allows user to edit multiline text and format the way it has to be displayed
Menu	It is used to create all kinds of menu used by an application

Example

PYTHON

from tkinter import *
from tkinter.ttk import *
   
# writing code needs to
# create the main window of
# the application creating
# main window object named root
root = Tk()
 
# giving title to the main window
root.title("First_Program")
 
# Label is what output will be
# show on the window
label = Label(root, text ="Hello World !").pack()
 
# calling mainloop method which is used
# when your application is ready to run
# and it tells the code to keep displaying
root.mainloop()