"""This program demonstrates tkinter menus.
Input:
None
Output:
Window with menus
References:
https://www.geeksforgeeks.org/right-click-menu-using-tkinter/
http://effbot.org/tkinterbook/tkinter-events-and-bindings.htm
https://www.tutorialspoint.com/python/python_gui_programming.htm
https://www.python-course.eu/python_tkinter.php
"""
import tkinter
class Root(tkinter.Tk):
"""Creates root window."""
_main_menu = None
_label = None
def __init__(self, *args, **kwargs):
tkinter.Tk.__init__(self, *args, **kwargs)
self.title("tkinter Menu Example")
self.geometry("%dx%d+0+0" % self.maxsize())
self._main_menu = MainMenu(self)
self._label = Label(self)
self._label.pack()
class MainMenu(tkinter.Menu):
"""Creates Main menu."""
@property
def root(self):
return self._root
def __init__(self, root, *args, **kwargs):
tkinter.Menu.__init__(self, root, *args, **kwargs)
self._root = root
file_menu = FileMenu(self, tearoff=0)
self.add_cascade(label="File", menu=file_menu)
root.config(menu=self)
class FileMenu(tkinter.Menu):
"""Creates File menu."""
def __init__(self, *args, **kwargs):
tkinter.Menu.__init__(self, *args, **kwargs)
self.add_command(label="Exit", command=self.master.quit)
class Label(tkinter.Label):
"""Creates label with popup menu."""
_menu = None
def __init__(self, *args, **kwargs):
tkinter.Label.__init__(self, *args, **kwargs,
text="Right-click to display menu",
width=320,
height=240)
self._menu = PopupMenu(self)
# Some systems use button 2, some use button 3.
# Binding to both.
self.bind("<Button-2>", self._menu.popup)
self.bind("<Button-3>", self._menu.popup)
class PopupMenu(tkinter.Menu):
"""Creates popup menu."""
def __init__(self, *args, **kwargs):
tkinter.Menu.__init__(self, *args, **kwargs,
tearoff=0)
self.add_command(label="Item 1", command=None)
self.add_command(label="Exit", command=exit)
def popup(self, event):
try:
self.tk_popup(event.x_root, event.y_root)
finally:
self.grab_release()
if __name__ == "__main__":
root = Root()
root.mainloop()
