Create a Text Editor in Python

By Sameer Saxena

In this tutorial, we will learn how to create a text editor like notepad in Python.

Text Editor is the first most and essential need of a software developer those are willing to write code or simply edit the existing one, working becomes easier due to the different functionality provided to the user, they are customizable according to the user needs. As though the ultimate work of a text editor is to edit files then too, choosing the best editor for programming is a trending topic of all-time in the tech industry, depending upon you can predict the power and importance of text editor in developer’s life.

So in this tutorial, we will be learning how to create a simple text editor using Python Programming Language. In this, we will be using the Tkinter library and two additional modules supported by Tkinter, ‘MessageBox’ and ‘FileDialog’ for providing some additional functionality to our editor.

Introduction to the libraries and modules used

  • Tkinter – This is one of the most Powerful, Widely Used and Platform Independent library available in Python for creating seamless and nice-looking GUI applications, it is very easy to use and understand different widgets provided by Tkinter.
  • MessageBox – This module provides the template classes and a variety of inbuilt functions for alerting the user, these message boxes can be an info message, an error message or ask yes/no message.
  • FileDialog – This module provides the classes and inbuilt functions for creating file or directory selection windows.

Creating Text Editor Using Python

Before getting started with code we need to install required libraries:

Installation:

$ sudo apt-get install python3-tk

Now, comes our Actual Code:

Source Code:

# Importing Required libraries & Modules
from tkinter import *
from tkinter import messagebox
from tkinter import filedialog

# Defining TextEditor Class
class TextEditor:

  # Defining Constructor
  def __init__(self,root):
    # Assigning root
    self.root = root
    # Title of the window
    self.root.title("TEXT EDITOR")
    # Window Geometry
    self.root.geometry("1200x700+200+150")
    # Initializing filename
    self.filename = None
    # Declaring Title variable
    self.title = StringVar()
    # Declaring Status variable
    self.status = StringVar()

    # Creating Titlebar
    self.titlebar = Label(self.root,textvariable=self.title,font=("times new roman",15,"bold"),bd=2,relief=GROOVE)
    # Packing Titlebar to root window
    self.titlebar.pack(side=TOP,fill=BOTH)
    # Calling Settitle Function
    self.settitle()

    # Creating Statusbar
    self.statusbar = Label(self.root,textvariable=self.status,font=("times new roman",15,"bold"),bd=2,relief=GROOVE)
    # Packing status bar to root window
    self.statusbar.pack(side=BOTTOM,fill=BOTH)
    # Initializing Status
    self.status.set("Welcome To Text Editor")

    # Creating Menubar
    self.menubar = Menu(self.root,font=("times new roman",15,"bold"),activebackground="skyblue")
    # Configuring menubar on root window
    self.root.config(menu=self.menubar)

    # Creating File Menu
    self.filemenu = Menu(self.menubar,font=("times new roman",12,"bold"),activebackground="skyblue",tearoff=0)
    # Adding New file Command
    self.filemenu.add_command(label="New",accelerator="Ctrl+N",command=self.newfile)
    # Adding Open file Command
    self.filemenu.add_command(label="Open",accelerator="Ctrl+O",command=self.openfile)
    # Adding Save File Command
    self.filemenu.add_command(label="Save",accelerator="Ctrl+S",command=self.savefile)
    # Adding Save As file Command
    self.filemenu.add_command(label="Save As",accelerator="Ctrl+A",command=self.saveasfile)
    # Adding Seprator
    self.filemenu.add_separator()
    # Adding Exit window Command
    self.filemenu.add_command(label="Exit",accelerator="Ctrl+E",command=self.exit)
    # Cascading filemenu to menubar
    self.menubar.add_cascade(label="File", menu=self.filemenu)

    # Creating Edit Menu
    self.editmenu = Menu(self.menubar,font=("times new roman",12,"bold"),activebackground="skyblue",tearoff=0)
    # Adding Cut text Command
    self.editmenu.add_command(label="Cut",accelerator="Ctrl+X",command=self.cut)
    # Adding Copy text Command
    self.editmenu.add_command(label="Copy",accelerator="Ctrl+C",command=self.copy)
    # Adding Paste text command
    self.editmenu.add_command(label="Paste",accelerator="Ctrl+V",command=self.paste)
    # Adding Seprator
    self.editmenu.add_separator()
    # Adding Undo text Command
    self.editmenu.add_command(label="Undo",accelerator="Ctrl+U",command=self.undo)
    # Cascading editmenu to menubar
    self.menubar.add_cascade(label="Edit", menu=self.editmenu)

    # Creating Help Menu
    self.helpmenu = Menu(self.menubar,font=("times new roman",12,"bold"),activebackground="skyblue",tearoff=0)
    # Adding About Command
    self.helpmenu.add_command(label="About",command=self.infoabout)
    # Cascading helpmenu to menubar
    self.menubar.add_cascade(label="Help", menu=self.helpmenu)

    # Creating Scrollbar
    scrol_y = Scrollbar(self.root,orient=VERTICAL)
    # Creating Text Area
    self.txtarea = Text(self.root,yscrollcommand=scrol_y.set,font=("times new roman",15,"bold"),state="normal",relief=GROOVE)
    # Packing scrollbar to root window
    scrol_y.pack(side=RIGHT,fill=Y)
    # Adding Scrollbar to text area
    scrol_y.config(command=self.txtarea.yview)
    # Packing Text Area to root window
    self.txtarea.pack(fill=BOTH,expand=1)

    # Calling shortcuts funtion
    self.shortcuts()

  # Defining settitle function
  def settitle(self):
    # Checking if Filename is not None
    if self.filename:
      # Updating Title as filename
      self.title.set(self.filename)
    else:
      # Updating Title as Untitled
      self.title.set("Untitled")

  # Defining New file Function
  def newfile(self,*args):
    # Clearing the Text Area
    self.txtarea.delete("1.0",END)
    # Updating filename as None
    self.filename = None
    # Calling settitle funtion
    self.settitle()
    # updating status
    self.status.set("New File Created")

  # Defining Open File Funtion
  def openfile(self,*args):
    # Exception handling
    try:
      # Asking for file to open
      self.filename = filedialog.askopenfilename(title = "Select file",filetypes = (("All Files","*.*"),("Text Files","*.txt"),("Python Files","*.py")))
      # checking if filename not none
      if self.filename:
        # opening file in readmode
        infile = open(self.filename,"r")
        # Clearing text area
        self.txtarea.delete("1.0",END)
        # Inserting data Line by line into text area
        for line in infile:
          self.txtarea.insert(END,line)
        # Closing the file	
        infile.close()
        # Calling Set title
        self.settitle()
        # Updating Status
        self.status.set("Opened Successfully")
    except Exception as e:
      messagebox.showerror("Exception",e)

  # Defining Save File Funtion
  def savefile(self,*args):
    # Exception handling
    try:
      # checking if filename not none
      if self.filename:
        # Reading the data from text area
        data = self.txtarea.get("1.0",END)
        # opening File in write mode
        outfile = open(self.filename,"w")
        # Writing Data into file
        outfile.write(data)
        # Closing File
        outfile.close()
        # Calling Set title
        self.settitle()
        # Updating Status
        self.status.set("Saved Successfully")
      else:
        self.saveasfile()
    except Exception as e:
      messagebox.showerror("Exception",e)

  # Defining Save As File Funtion
  def saveasfile(self,*args):
    # Exception handling
    try:
      # Asking for file name and type to save
      untitledfile = filedialog.asksaveasfilename(title = "Save file As",defaultextension=".txt",initialfile = "Untitled.txt",filetypes = (("All Files","*.*"),("Text Files","*.txt"),("Python Files","*.py")))
      # Reading the data from text area
      data = self.txtarea.get("1.0",END)
      # opening File in write mode
      outfile = open(untitledfile,"w")
      # Writing Data into file
      outfile.write(data)
      # Closing File
      outfile.close()
      # Updating filename as Untitled
      self.filename = untitledfile
      # Calling Set title
      self.settitle()
      # Updating Status
      self.status.set("Saved Successfully")
    except Exception as e:
      messagebox.showerror("Exception",e)

  # Defining Exit Funtion
  def exit(self,*args):
    op = messagebox.askyesno("WARNING","Your Unsaved Data May be Lost!!")
    if op>0:
      self.root.destroy()
    else:
      return

  # Defining Cut Funtion
  def cut(self,*args):
    self.txtarea.event_generate("<<Cut>>")

  # Defining Copy Funtion
  def copy(self,*args):
      		self.txtarea.event_generate("<<Copy>>")

  # Defining Paste Funtion
  def paste(self,*args):
    self.txtarea.event_generate("<<Paste>>")

  # Defining Undo Funtion
  def undo(self,*args):
    # Exception handling
    try:
      # checking if filename not none
      if self.filename:
        # Clearing Text Area
        self.txtarea.delete("1.0",END)
        # opening File in read mode
        infile = open(self.filename,"r")
        # Inserting data Line by line into text area
        for line in infile:
          self.txtarea.insert(END,line)
        # Closing File
        infile.close()
        # Calling Set title
        self.settitle()
        # Updating Status
        self.status.set("Undone Successfully")
      else:
        # Clearing Text Area
        self.txtarea.delete("1.0",END)
        # Updating filename as None
        self.filename = None
        # Calling Set title
        self.settitle()
        # Updating Status
        self.status.set("Undone Successfully")
    except Exception as e:
      messagebox.showerror("Exception",e)

  # Defining About Funtion
  def infoabout(self):
    messagebox.showinfo("About Text Editor","A Simple Text Editor\nCreated using Python.")

  # Defining shortcuts Funtion
  def shortcuts(self):
    # Binding Ctrl+n to newfile funtion
    self.txtarea.bind("<Control-n>",self.newfile)
    # Binding Ctrl+o to openfile funtion
    self.txtarea.bind("<Control-o>",self.openfile)
    # Binding Ctrl+s to savefile funtion
    self.txtarea.bind("<Control-s>",self.savefile)
    # Binding Ctrl+a to saveasfile funtion
    self.txtarea.bind("<Control-a>",self.saveasfile)
    # Binding Ctrl+e to exit funtion
    self.txtarea.bind("<Control-e>",self.exit)
    # Binding Ctrl+x to cut funtion
    self.txtarea.bind("<Control-x>",self.cut)
    # Binding Ctrl+c to copy funtion
    self.txtarea.bind("<Control-c>",self.copy)
    # Binding Ctrl+v to paste funtion
    self.txtarea.bind("<Control-v>",self.paste)
    # Binding Ctrl+u to undo funtion
    self.txtarea.bind("<Control-u>",self.undo)

# Creating TK Container
root = Tk()
# Passing Root to TextEditor Class
TextEditor(root)
# Root Window Looping
root.mainloop()

I would suggest you, read the code thoroughly because it is very easy to understand and I have added comments for almost every single line for your better understanding.

Output:

Run the text editor file:

Create a Text Editor in Python

Click on the file menu and select open command:

Click on the file menu and select open command

Select the file you want to open:

Select the file you want to open

Click on open Button:

Python text editor

Now you can enjoy editing your file:

Click on open Button - edit text file in Python

So In this way, you can create a simple text editor using Python and Tkinter library. I hope this tutorial was helpful to you, thank you ‘Keep Learning Keep Coding’.

One response to “Create a Text Editor in Python”

  1. david says:
    October 6, 2020 at 12:33 am

    Hey, I love the tutorial but you used read mode in askopenfilename that is only meant to read not edit or write to the file content.

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