gui_2.py

import tkinter as tk
from tkinter import messagebox

class Mygui:
    def __init__ (self):

        self.root=tk.Tk()

        self.menubar=tk.Menu(self.root)

        self.root.title("Hello World!!")
        self.root.geometry("700x700")

        self.filemenu=tk.Menu(self.menubar,tearoff=0)
        self.filemenu.add_command(label="close",command=self.on_closing)
        self.filemenu.add_separator()
        self.filemenu.add_command(label="close without question",command=exit)

        self.actionmenu=tk.Menu(self.menubar,tearoff=0)
        self.actionmenu.add_command(label="Show Message",command=self.show_message)

        self.menubar.add_cascade(menu=self.filemenu,label="File")
        self.menubar.add_cascade(menu=self.actionmenu,label="Action")

        self.root.config(menu=self.menubar)
        self.label=tk.Label(self.root,text="Your message",font=("Arial",18))
        self.label.pack(padx=10,pady=10)

        self.textbox=tk.Text(self.root,height=5,font=("Arial",16))
        self.textbox.bind("<KeyPress>",self.shortcut)
        self.textbox.pack(padx=10,pady=10)

        self.check_state=tk.IntVar()

        self.check=tk.Checkbutton(self.root,text="show message box",font=("Arial",16),variable=self.check_state)
        self.check.pack(padx=10,pady=10)

        self.button=tk.Button(self.root,text="show message",font=("Arial",18),command=self.show_message)
        self.button.pack(padx=10,pady=10)

        self.clearbtn=tk.Button(self.root,text="clear",font=("Arial",18),command=self.clear)
        self.clearbtn.pack(padx=10,pady=10)
        self.root.protocol("WM_DELETE_WINDOW",self.on_closing)
        self.root.mainloop()

    def show_message(self):
        if self.check_state.get()==0:
            print(self.textbox.get('1.0',tk.END))
        else:
            messagebox.showinfo(title="Message",message=self.textbox.get('1.0',tk.END))

    def shortcut(self,event):
        if event.state== 12 and event.keysym ==  "Return":
                self.show_message()

    def on_closing(self):
        if messagebox.askyesno(title="Quit?",message="do you really want to quit? "):
            self.root.destroy()
    
    def clear(self):
        self.textbox.delete('1.0',tk.END)
Mygui()