dialog_window.py

import tkinter as tk
from tkinter import ttk
import os

class Dialog(tk.Toplevel):

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

        tk.Toplevel.__init__(self, parent)
        self.transient(parent)
        self.resizable(height=False, width=False)

        if title:
            self.title(title)

        self.parent = parent

        self.result = None

        body = ttk.Frame(self)
        self.initial_focus = self.body(body)
        body.pack(padx=5, pady=5)

        self.buttonbox()

        self.grab_set()

        if not self.initial_focus:
            self.initial_focus = self

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

        self.geometry("+%d+%d" % (parent.winfo_rootx()+50,
                                  parent.winfo_rooty()+50))

        self.initial_focus.focus_set()

        self.wait_window(self)

    #
    # construction hooks


    def body(self, master):
        # create dialog body.  return widget that should have
        # initial focus.  this method should be overridden

        pass

    def buttonbox(self):
        # add standard button box. override if you don't want the
        # standard buttons

        box = ttk.Frame(self)

        w = ttk.Button(box, text="OK", width=10, command=self.ok, default=tk.ACTIVE)
        w.pack(side=tk.LEFT, padx=5, pady=5)
        w = ttk.Button(box, text="Cancel", width=10, command=self.cancel)
        w.pack(side=tk.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()

        self.apply()

        self.cancel()

    def cancel(self, event=None):

        # put focus back to the parent window
        self.parent.focus_set()
        self.destroy()

    #
    # command hooks

    def validate(self):

        return 1 # override

    def apply(self):

        pass # override
    def _calc_cb_length(self):
        upper = 40
        lower = 20
        if self.node_list:
            return max(min(max([ len(''.join(x)) + 1
                for x in self.node_list ]), upper), lower)
        else:
            return lower