Read a text file using Python Tkinter

Graphical User Interfaces (GUIs) are an essential aspect of modern software development, providing users with interactive and visually appealing applications. Python’s Tkinter library is a robust tool for creating GUIs, and in this article, we will delve into the process of building a Tkinter application that reads and displays the content of a text file.

Read a Text File Using Python Tkinter

Below is the step-by-step procedure by which we can read a text file using Python Tkinter in Python:

Step 1: Installation

We will install the following modules before starting with the program.

• Install Python
• Install Tkinter

Step 2: Import Tkinter

Start by importing the Tkinter module and the `filedialog` submodule.

Python3

import tkinter as tk
from tkinter import filedialog

Step 3: Create the main window

Create the main Tkinter window using the `Tk` class.

Python3

root = tk.Tk()
root.title("Text File Reader")

Step 4: Create a Text widget

Add a `Text` widget to the window. This widget will serve as the area to display the content of the text file.

Python3

text_widget = tk.Text(root, wrap="word", width=40, height=10)
text_widget.pack(pady=10)

Step 5: Create a button to open the file

Include a button that users can click to open a text file.

Python3

open_button = tk.Button(root, text="Open File", command=open_file)
open_button.pack(pady=10)

Step 6: Define the `open_file` function

Create a function that prompts the user to select a text file and displays its content in the `Text` widget.

Python3

def open_file():
    file_path = filedialog.askopenfilename(
        title="Select a Text File", filetypes=[("Text files", "*.txt")])
    if file_path:
        with open(file_path, 'r') as file:
            content = file.read()
            text_widget.delete(1.0, tk.END)  # Clear previous content
            text_widget.insert(tk.END, content)

Step 7: Run the Tkinter event loop

Start the Tkinter event loop to run the GUI application.

Python3

root.mainloop()

Full Code Implementation

In this code, a simple Tkinter GUI application is created to open and display the content of a text file. The program utilizes the `tkinter` library, implements a function (`open_file`) to open a text file through a file dialog, and displays the file’s content in a Tkinter Text widget within the main window.

Python3

import tkinter as tk
from tkinter import filedialog

def open_file():
    file_path = filedialog.askopenfilename(
        title="Select a Text File", filetypes=[("Text files", "*.txt")])
    if file_path:
        with open(file_path, 'r') as file:
            content = file.read()
            text_widget.delete(1.0, tk.END)  # Clear previous content
            text_widget.insert(tk.END, content)


# Create the main window
root = tk.Tk()
root.title("Text File Reader")

# Create a Text widget to display the content
text_widget = tk.Text(root, wrap="word", width=40, height=10)
text_widget.pack(pady=10)

# Create a button to open the file
open_button = tk.Button(root, text="Open File", command=open_file)
open_button.pack(pady=10)

# Run the Tkinter event loop
root.mainloop()

Output:

Tkinter window

Conclusion

This article provided a comprehensive guide on using Tkinter to build a text file reader GUI application in Python. By understanding the concepts of Tkinter widgets and file handling, developers can create powerful applications that enhance user interaction and experience. The example and step-by-step guide serve as a foundation for more complex projects involving file interactions within a graphical interface.