Python Tkinter JSON viewer

Last update on August 19 2025 11:25:22 (UTC/GMT +8 hours)

Write a Python program that reads and displays data from a JSON file in a user-friendly format using Tkinter labels and frames.

Sample Solution:

Python Code:

import tkinter as tk
from tkinter import ttk
import json

class JSONViewerApp:
    def __init__(self, root):
        self.root = root
        self.root.title("JSON Viewer")

        # Create a Frame for displaying JSON data
        self.frame = ttk.Frame(root)
        self.frame.pack(padx=20, pady=20, fill=tk.BOTH, expand=True)

        # Create a Text widget for displaying JSON content
        self.text_widget = tk.Text(self.frame, wrap=tk.WORD)
        self.text_widget.pack(side=tk.LEFT, fill=tk.BOTH, expand=True)

        # Create a Scrollbar for the Text widget
        self.scrollbar = ttk.Scrollbar(self.frame, command=self.text_widget.yview)
        self.scrollbar.pack(side=tk.RIGHT, fill=tk.Y)
        self.text_widget.config(yscrollcommand=self.scrollbar.set)

        # Load and display JSON data
        self.load_json_data("sample.json")  # Replace with your JSON file path

    def load_json_data(self, json_file):
        try:
            # Load JSON data from the file
            with open(json_file, "r") as file:
                data = json.load(file)

            # Format JSON data as a string and display it in the Text widget
            formatted_json = json.dumps(data, indent=4)
            self.text_widget.insert(tk.END, formatted_json)

            # Make the Text widget read-only
            self.text_widget.config(state=tk.DISABLED)

        except FileNotFoundError:
            self.text_widget.insert(tk.END, "File not found.")
            self.text_widget.config(state=tk.DISABLED)

if __name__ == "__main__":
    root = tk.Tk()
    app = JSONViewerApp(root)
    root.mainloop()

Explanation:

In the exercise above -

Import the necessary libraries:

tkinter and ttk for creating the graphical user interface.
json for handling JSON data.

Define a class named JSONViewerApp that encapsulates the application's functionality.
Inside the class constructor (__init__), the following components are created:

The main application window is created (root) and given the title "JSON Viewer."
A frame (frame) is created to hold the JSON data display area.
A "Text" widget (text_widget) is created to display JSON content. It's placed on the left side of the frame and configured to wrap text and expand to fill available space.
A vertical scrollbar (scrollbar) is added to the frame, allowing users to scroll through the JSON content in the Text widget.

The "load_json_data()" method loads and displays JSON data from a file. It takes the JSON file path as an argument.

The method attempts to open the specified JSON file using with open(). If the file is found and opened successfully, it reads and loads the JSON data.
The loaded JSON data is formatted using "json.dumps()" method with an indentation of 4 spaces to make it more readable.
The formatted JSON data is inserted into the "Text" widget (text_widget) at the end of the widget's content.
The "Text" widget is set to a read-only state (tk.DISABLED) to prevent users from editing the displayed JSON.
If the specified JSON file is not found, a message "File not found" is inserted into the "Text" widget.

In the main section (if name == "__main__":), the Tkinter root window is created, an instance of JSONViewerApp is created, and the Tkinter main event loop (root.mainloop()) is started to run the application.