Python Tkinter JSON viewer

Python Tkinter File Operations and Integration: Exercise-4 with Solution

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.

Output:

Flowchart:

Python Code Editor:

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