Python Tkinter GUI - Search Files In Directory For Instances Of A String

Question

This script opens a basic form which allows one to search all files in a directory for instances of a string, before outputting results to a textbox and CSV (found in the script location). Each line outputted is of the format:

Word {string} in {file} on line {line number}: {full line}

Steps:

1. Specify Directory
2. Input string you would like to search for
3. Toggle ignore case on or off
4. Click Go.

Notes:

This is not completely finished yet. Script will only search basic TXT files. I'm also a beginner with Tkinter/GUIs, so haven't moved buttons around, etc. I've just added the buttons & labels one after the other. This will eventually be rectified. There's also an issue where if I'm searching a large directory of files, the form will look like it's frozen until it's finished searching. Finally, I may have went overboard on some of the error handling. I'm newish to this as well.

I'm trying to be a better programmer, particularly with structuring and readability, so any constructive criticism would be much appreciated.

from tkinter import filedialog

from tkinter.scrolledtext import ScrolledText

import pandas as pd

import tkinter as tk

import os

import re

import sys

################ FUNCTIONS ################

def save_to_file(wordlist):
    """Save list to CSV format and save CSV to script directory"""
    script_directory = os.path.dirname(sys.argv[0]) # Path where script is being run from
    df = pd.DataFrame(data={"Results": wordlist})
    df.to_csv(script_directory+"/mycsv.csv", sep=",", index=False, line_terminator='\n')
    
def print_to_textbox(wordlist):
    """Print all lines in wordlist to textbox"""
    for lines in wordlist:
        text_box.insert("end", "\n"+lines)
    if len(wordlist) == 0:
        text_box.insert("1.0", "\nNothing To Display")

def browse_button():
    """Button will open a window for directory selection"""
    global folder_path
    selected_directory = filedialog.askdirectory()
    folder_path.set(selected_directory)
    
def search_files():
    """Search all files in specified directory"""
    folderPath = folder_path.get()
    searchString = string_entry.get()
    text_box.delete("1.0", tk.END)
    
    # Set word case option on/off.
    if var1.get() == 1:
        IGNOREWORDCASE = True
    else:
        IGNOREWORDCASE = False
        
    # List to store all lines where string is found.
    wordlist = []  
    
    # Loop through all files and search for string, line by line.
    for (path, directories, files) in os.walk(folderPath, topdown=True):
        for file in files:
            filepath = os.path.join(path, file)
            
            try: 
                
                with open(filepath, 'r') as currentfile:          
                        for lineNum, line in enumerate(currentfile, 1):  
                            line = line.strip()
                            match = re.search(searchString, line, re.IGNORECASE) if IGNOREWORDCASE else re.search(searchString, line)
                            if match:
                                word = f"Word '{searchString}' in '{file}' on line {lineNum}: {line}"
                                wordlist.append(word)
                                
            except IOError as ex:
                words = f"Error; {file}; {ex}"
                wordlist.insert(0, words)
                
            except EnvironmentError as ex:
                words = f"Error; {file}; {ex}"
                wordlist.insert(0, words)
                
            except OSError as ex:
                words = f"Error; {file}; {ex}"
                wordlist.insert(0, words)
                
            except UnicodeDecodeError as ex:
                words = f"Error; {file}; {ex}"
                wordlist.insert(0, words)
                
            except:
                words = f"Error; {file}"
                wordlist.insert(0, words)

    # Print all lines to text box.
    print_to_textbox(wordlist)
    
    # Save to file.
    save_to_file(wordlist)
                
################ TKINTER SCRIPT ################

# Setup Window.
window = tk.Tk()
window.geometry("900x500")
window.title("String Search")

# Button to select directory.
select_directory = tk.Button(window, text = "Select Directory", command=browse_button)
select_directory.pack()

# Label to store chosen directory.
folder_path = tk.StringVar()
directory_label = tk.Label(window, textvariable = folder_path, bg="#D3D3D3", width=70)
directory_label.pack()

# Entry to type search string.
string_entry = tk.Entry(window, bg="#D3D3D3")
string_entry.pack()

# Check button to turn ignore case on/off.
var1 = tk.IntVar()
stringCase_select = tk.Checkbutton(window, text='Ignore Case',variable=var1, onvalue=1, offvalue=0)
stringCase_select.pack()

# Button to run main script.
go_button = tk.Button(window, text="Go", command=search_files)
go_button.pack()

# Button to quit the app.
quit_button = tk.Button(window, text = "Quit", command=window.quit)
quit_button.pack()

# Text box to display output of main text.
text_box = ScrolledText(width=110, borderwidth=2, relief="sunken", padx=20)
text_box.pack()

# Button to clear the text box display.
clear_button = tk.Button(window, text = "Clear", command = lambda: text_box.delete("1.0", tk.END))
clear_button.pack()

# Run an event loop.
window.mainloop()

Answer 1

PEP-8

To maintain consistency while writing code, Python code follows the PEP-8 naming convention. For example

Source

Function names should be lowercase, with words separated by underscores as necessary to improve readability.

Variable names follow the same convention as function names.

The library that you are currently using, which is tkinter also follows the same naming convention. You can see that classes like Button,Canvas, and StringVar(). All follow the CamelCase since they are classes.

Positioning widgets in your application

Although .pack() works, you will soon see its limits when you start trying to position the widgets in specific places, like an exit button typically stays in the corner, A title usually is placed at the top. In these scenarios .pack() is just very limited.

A common way is to use .place() to position widgets in your application. It has many arguments like bordermode and anchor to customize your task, the two main are x and y which are basically just the horizontal and vertical points at which your widget will be placed.

Here is a simple Tkinter window of geometry("500x500") I have created to show the usage of place(). It also has a Label as a simple widget.

Example: widget.place(x = 300,y = 50)

You get to decide where you want to place your widgets accurately.

Structuring a Tk application

@Reinderien suggested your TKINTER_SCRIPT into a function. This makes sense because you already have good functions like search_files(), why would you have your Tkinter application in the main scope?

While some might disagree, my suggestion is that you opt for an Object-oriented approach, which will help keep your code clean. In your situation, it makes sense to have a single MainApplication() class. Here is a simple example of what that would look like

class MainApplication:
    def __init__(self,window,size = "500x500"):
        self.window = window
        window.geometry(size)
        self.entry_box = # Entry box widget
        self.title = # Title label 
        # More widgets that are relevant to MainApplication

    def close_application():
        # print any messages on window like "Thank you for using..."
        self.window.close()

root = tk.Tk()
window = MainApplication(root)

root.mainloop()

Structuring a Tkinter application

Small suggestions

• Use root.iconbitmap( #icon image ) to set a 16x16 icon for your tkinter application, this will appear instead of the little feather that comes
• Tkinter has a huge variety of widgets, it is possible that you might find a new one from this list of main widgets that might be perfect for your application.
• message boxes in tkinter will be suitable for when a user might do something wrong, or maybe you want to get a confirmation.

Example of a message box

Answer 2

Consider using PEP-484 type hints for your function signatures.

Use a linter like pyflakes, flake8 or black that will give you a number of suggestions about your code format.

Move your TKINTER SCRIPT into one or more functions, instead of in global scope.

Use pathlib, so that this:

script_directory+"/mycsv.csv

can be

Path(script_directory) / 'mycsv.csv'

If var1.get() returns 0/1, then you can simply write

IGNORE_WORD_CASE = bool(var1.get())

though you should give var1 a more meaningful name.