notepad.py

import tkinter
import os
from tkinter import *

from tkinter.messagebox import *

from tkinter.filedialog import *


class Notepad:
    __root = Tk()

    # default window width and height

    __thisWidth = 300
    __thisHeight = 300
    __thisTextArea = Text(__root)
    __thisMenuBar = Menu(__root)
    __thisFileMenu = Menu(__thisMenuBar, tearoff=0)
    __thisEditMenu = Menu(__thisMenuBar, tearoff=0)
    __thisHelpMenu = Menu(__thisMenuBar, tearoff=0)

    __thisScrollBar = Scrollbar(__thisTextArea)
    __file = None

    def __init__(self, **kwargs):
        try:
            self.__root.wm_iconbitmap("Notepad.ico")
        except:
            pass

        try:
            self.__thisWidth = kwargs["width"]
        except KeyError:
            pass
        try:
            self.__thisHeight = kwargs["height"]
        except KeyError:
            pass

        # set window text
        self.__root.title("Untitled -Notepad")

        # center window
        screenWidth = self.__root.winfo_screenwidth()
        screenHeight = self.__root.winfo_screenheight()

        # for left align
        left = (screenWidth / 2) - (self.__thisWidth / 2)

        # for top align
        top = (screenHeight / 2) - (self.__thisHeight / 2)

        # for top and bottom
        self.__root.geometry('%dx%d+%d+%d' %
                             (self.__thisWidth, self.__thisHeight, left, top))

        # to make text area resizable
        self.__root.grid_rowconfigure(0, weight=1)
        self.__root.grid_columnconfigure(0, weight=1)

        # add control (widgets)
        self.__thisTextArea.grid(sticky=N + E + S + W)

        # to open a new file
        self.__thisFileMenu.add_command(label="New", command=self.__newFile)

        # to open a existing file
        self.__thisFileMenu.add_command(label="Open", command=self.__openFile)

        # to  save a file
        self.__thisFileMenu.add_command(label="Save", command=self.__saveFile)

        # to create a line in the  dialog
        self.__thisFileMenu.add_separator()
        self.__thisFileMenu.add_command(
            label="Exit", command=self.__quitApplication)
        self.__thisMenuBar.add_cascade(label='File', menu=self.__thisFileMenu)

        # to give a feature cut
        self.__thisEditMenu.add_command(label="Cut", command=self.__cut)

        # to give a feature copy
        self.__thisEditMenu.add_command(label="Copy", command=self.__copy)

        # to give a feature paste
        self.__thisEditMenu.add_command(label="Paste", command=self.__paste)

        # to give feautres to editing menu
        self.__thisMenuBar.add_cascade(label="Edit", menu=self.__thisEditMenu)

        # to create feature description of notepad
        self.__thisHelpMenu.add_command(
            label="About Notepad", command=self.__showAbout)

        self.__thisMenuBar.add_cascade(label="Help", menu=self.__thisHelpMenu)

        self.__root.config(menu=self.__thisMenuBar)

        self.__thisScrollBar.pack(side=RIGHT, fill=Y)

        # scrollbar will adjysct automatically to content
        self.__thisScrollBar.config(command=self.__thisTextArea.yview)
        self.__thisTextArea.config(yscrollcommand=self.__thisScrollBar.set)

    def __quitApplication(self):
        self.__root.destroy()

        # exit

    def __showAbout(self):
        showinfo("Notepad ", "SSS")

    def __openFile(self):
        self.__file = askopenfilename(defaultextension=".txt ", filetypes=[
                                      ("All Files", "*.*"), ("Text Documents", "*.txt")])

        if self.__file == "":
            # no file present
            self.__file = None

        else:
            self.__root.title(os.path.basename(self.__file) + " - Notepad")
            self.__thisTextArea.delete(1.0, END)

            file = open(self.__file, "r")

            self.__thisTextArea.insert(1.0, file.read())

            file.close()

    def __newFile(self):
        self.__root.title("Untitled , Notepad")
        self.__file = None
        self.__thisTextArea.delete(1.0, END)

    def __saveFile(self):
        if self.__file == None:
            self.__file = asksaveasfilename(initialfile='Untitled.txt', defaultextension=".txt ", filetypes=[
                ("All Files", " *.*"), ("Text Documents", "*.txt")])

            if self.__file == "":
                self.__file = None

            else:
                file = open(self.__file, "w")
                file.write(self.__thisTextArea.get(1.0, END))
                file.close()
                # change the window title
                self.__root.title(os.path.basename(self.__file) + " - Notepad")
        else:
            file = open(self.__file, "w")
            file.write(self.__thisTextArea.get(1.0, END))
            file.close()

    def __cut(self):
        self.__thisTextArea.event_generate("<<Cut>>")

    def __copy(self):
        self.__thisTextArea.event_generate("<<Copy>>")

    def __paste(self):
        self.__thisTextArea.event_generate("<<Paste>>")

    def run(self):

        # run main application
        self.__root.mainloop()


notepad = Notepad(width=600, height=400)
notepad.run()