#

# An Introduction to Tkinter

#

# Copyright (c) 1997 by Fredrik Lundh

#

# This copyright applies to Dialog, askinteger, askfloat and asktring

#

# fredrik@pythonware.com

# http://www.pythonware.com

#

"""This modules handles dialog boxes.

It contains the following public symbols:

SimpleDialog -- A simple but flexible modal dialog box

Dialog -- a base class for dialogs

askinteger -- get an integer from the user

askfloat -- get a float from the user

askstring -- get a string from the user

"""

from tkinter import *

from tkinter import _get_temp_root, _destroy_temp_root

from tkinter import messagebox

class SimpleDialog:

def __init__(self, master,

text='', buttons=[], default=None, cancel=None,

title=None, class_=None):

if class_:

self.root = Toplevel(master, class_=class_)

else:

self.root = Toplevel(master)

if title:

self.root.title(title)

self.root.iconname(title)

_setup_dialog(self.root)

self.message = Message(self.root, text=text, aspect=400)

self.message.pack(expand=1, fill=BOTH)

self.frame = Frame(self.root)

self.frame.pack()

self.num = default

self.cancel = cancel

self.default = default

self.root.bind('<Return>', self.return_event)

for num in range(len(buttons)):

s = buttons[num]

b = Button(self.frame, text=s,

command=(lambda self=self, num=num: self.done(num)))

if num == default:

b.config(relief=RIDGE, borderwidth=8)

b.pack(side=LEFT, fill=BOTH, expand=1)

self.root.protocol('WM_DELETE_WINDOW', self.wm_delete_window)

self.root.transient(master)

_place_window(self.root, master)

def go(self):

self.root.wait_visibility()

self.root.grab_set()

self.root.mainloop()

self.root.destroy()

return self.num

def return_event(self, event):

if self.default is None:

self.root.bell()

else:

self.done(self.default)

def wm_delete_window(self):

if self.cancel is None:

self.root.bell()

else:

self.done(self.cancel)

def done(self, num):

self.num = num

self.root.quit()

class Dialog(Toplevel):

'''Class to open dialogs.

This class is intended as a base class for custom dialogs

'''

def __init__(self, parent, title = None):

'''Initialize a dialog.

Arguments:

parent -- a parent window (the application window)

title -- the dialog title

'''

master = parent

if master is None:

master = _get_temp_root()

Toplevel.__init__(self, master)

self.withdraw() # remain invisible for now

# If the parent is not viewable, don't

# make the child transient, or else it

# would be opened withdrawn

if parent is not None and parent.winfo_viewable():

self.transient(parent)

if title:

self.title(title)

_setup_dialog(self)

self.parent = parent

self.result = None

body = Frame(self)

self.initial_focus = self.body(body)

body.pack(padx=5, pady=5)

self.buttonbox()

if self.initial_focus is None:

self.initial_focus = self

self.protocol("WM_DELETE_WINDOW", self.cancel)

_place_window(self, parent)

self.initial_focus.focus_set()

# wait for window to appear on screen before calling grab_set

self.wait_visibility()

self.grab_set()

self.wait_window(self)

def destroy(self):

'''Destroy the window'''

self.initial_focus = None

Toplevel.destroy(self)

_destroy_temp_root(self.master)

#

# construction hooks

def body(self, master):

'''create dialog body.

return widget that should have initial focus.

This method should be overridden, and is called

by the __init__ method.

'''

pass

def buttonbox(self):

'''add standard button box.

override if you do not want the standard buttons

'''

box = Frame(self)

w = Button(box, text="OK", width=10, command=self.ok, default=ACTIVE)

w.pack(side=LEFT, padx=5, pady=5)

w = Button(box, text="Cancel", width=10, command=self.cancel)

w.pack(side=LEFT, padx=5, pady=5)

self.bind("<Return>", self.ok)

self.bind("<Escape>", self.cancel)

box.pack()

#

# standard button semantics

def ok(self, event=None):

if not self.validate():

self.initial_focus.focus_set() # put focus back

return

self.withdraw()

self.update_idletasks()

try:

self.apply()

finally:

self.cancel()

def cancel(self, event=None):

# put focus back to the parent window

if self.parent is not None:

self.parent.focus_set()

self.destroy()

#

# command hooks

def validate(self):

'''validate the data

This method is called automatically to validate the data before the

dialog is destroyed. By default, it always validates OK.

'''

return 1 # override

def apply(self):

'''process the data

This method is called automatically to process the data, *after*

the dialog is destroyed. By default, it does nothing.

'''

pass # override

# Place a toplevel window at the center of parent or screen

# It is a Python implementation of ::tk::PlaceWindow.

def _place_window(w, parent=None):

w.wm_withdraw() # Remain invisible while we figure out the geometry

w.update_idletasks() # Actualize geometry information

minwidth = w.winfo_reqwidth()

minheight = w.winfo_reqheight()

maxwidth = w.winfo_vrootwidth()

maxheight = w.winfo_vrootheight()

if parent is not None and parent.winfo_ismapped():

x = parent.winfo_rootx() + (parent.winfo_width() - minwidth) // 2

y = parent.winfo_rooty() + (parent.winfo_height() - minheight) // 2

vrootx = w.winfo_vrootx()

vrooty = w.winfo_vrooty()

x = min(x, vrootx + maxwidth - minwidth)

x = max(x, vrootx)

y = min(y, vrooty + maxheight - minheight)

y = max(y, vrooty)

if w._windowingsystem == 'aqua':

# Avoid the native menu bar which sits on top of everything.

y = max(y, 22)

else:

x = (w.winfo_screenwidth() - minwidth) // 2

y = (w.winfo_screenheight() - minheight) // 2

w.wm_maxsize(maxwidth, maxheight)

w.wm_geometry('+%d+%d' % (x, y))

w.wm_deiconify() # Become visible at the desired location

def _setup_dialog(w):

if w._windowingsystem == "aqua":

w.tk.call("::tk::unsupported::MacWindowStyle", "style",

w, "moveableModal", "")

elif w._windowingsystem == "x11":

w.wm_attributes("-type", "dialog")

# --------------------------------------------------------------------

# convenience dialogues

class _QueryDialog(Dialog):

def __init__(self, title, prompt,

initialvalue=None,

minvalue = None, maxvalue = None,

parent = None):

self.prompt = prompt

self.minvalue = minvalue

self.maxvalue = maxvalue

self.initialvalue = initialvalue

Dialog.__init__(self, parent, title)

def destroy(self):

self.entry = None

Dialog.destroy(self)

def body(self, master):

w = Label(master, text=self.prompt, justify=LEFT)

w.grid(row=0, padx=5, sticky=W)

self.entry = Entry(master, name="entry")

self.entry.grid(row=1, padx=5, sticky=W+E)

if self.initialvalue is not None:

self.entry.insert(0, self.initialvalue)

self.entry.select_range(0, END)

return self.entry

def validate(self):

try:

result = self.getresult()

except ValueError:

messagebox.showwarning(

"Illegal value",

self.errormessage + "\nPlease try again",

parent = self

)

return 0

if self.minvalue is not None and result < self.minvalue:

messagebox.showwarning(

"Too small",

"The allowed minimum value is %s. "

"Please try again." % self.minvalue,

parent = self

)

return 0

if self.maxvalue is not None and result > self.maxvalue:

messagebox.showwarning(

"Too large",

"The allowed maximum value is %s. "

"Please try again." % self.maxvalue,

parent = self

)

return 0

self.result = result

return 1

class _QueryInteger(_QueryDialog):

errormessage = "Not an integer."

def getresult(self):

return self.getint(self.entry.get())

def askinteger(title, prompt, **kw):

'''get an integer from the user

Arguments:

title -- the dialog title

prompt -- the label text

**kw -- see SimpleDialog class

Return value is an integer

'''

d = _QueryInteger(title, prompt, **kw)

return d.result

class _QueryFloat(_QueryDialog):

errormessage = "Not a floating point value."

def getresult(self):

return self.getdouble(self.entry.get())

def askfloat(title, prompt, **kw):

'''get a float from the user

Arguments:

title -- the dialog title

prompt -- the label text

**kw -- see SimpleDialog class

Return value is a float

'''

d = _QueryFloat(title, prompt, **kw)

return d.result

class _QueryString(_QueryDialog):

def __init__(self, *args, **kw):

if "show" in kw:

self.__show = kw["show"]

del kw["show"]

else:

self.__show = None

_QueryDialog.__init__(self, *args, **kw)

def body(self, master):

entry = _QueryDialog.body(self, master)

if self.__show is not None:

entry.configure(show=self.__show)

return entry

def getresult(self):

return self.entry.get()

def askstring(title, prompt, **kw):

'''get a string from the user

Arguments:

title -- the dialog title

prompt -- the label text

**kw -- see SimpleDialog class

Return value is a string

'''

d = _QueryString(title, prompt, **kw)

return d.result

if __name__ == '__main__':

def test():

root = Tk()

def doit(root=root):

d = SimpleDialog(root,

text="This is a test dialog. "

"Would this have been an actual dialog, "

"the buttons below would have been glowing "

"in soft pink light.\n"

"Do you believe this?",

buttons=["Yes", "No", "Cancel"],

default=0,

cancel=2,

title="Test Dialog")

print(d.go())

print(askinteger("Spam", "Egg count", initialvalue=12*12))

print(askfloat("Spam", "Egg weight\n(in tons)", minvalue=1,

maxvalue=100))

print(askstring("Spam", "Egg label"))

t = Button(root, text='Test', command=doit)

t.pack()

q = Button(root, text='Quit', command=t.quit)

q.pack()

t.mainloop()

test()