Lib/lib-tk/tkSimpleDialog.py

   1 #
   2 # An Introduction to Tkinter
   3 # tkSimpleDialog.py
   4 #
   5 # Copyright (c) 1997 by Fredrik Lundh
   6 #
   7 # fredrik@pythonware.com
   8 # http://www.pythonware.com
   9 #
  10
  11 # --------------------------------------------------------------------
  12 # dialog base class
  13
  14 '''Dialog boxes
  15
  16 This module handles dialog boxes. It contains the following
  17 public symbols:
  18
  19 Dialog -- a base class for dialogs
  20
  21 askinteger -- get an integer from the user
  22
  23 askfloat -- get a float from the user
  24
  25 askstring -- get a string from the user
  26 '''
  27
  28 from Tkinter import *
  29 import os
  30
  31 class Dialog(Toplevel):
  32
  33     '''Class to open dialogs.
  34
  35     This class is intended as a base class for custom dialogs
  36     '''
  37
  38     def __init__(self, parent, title = None):
  39
  40         '''Initialize a dialog.
  41
  42         Arguments:
  43
  44             parent -- a parent window (the application window)
  45
  46             title -- the dialog title
  47         '''
  48         Toplevel.__init__(self, parent)
  49         self.transient(parent)
  50
  51         if title:
  52             self.title(title)
  53
  54         self.parent = parent
  55
  56         self.result = None
  57
  58         body = Frame(self)
  59         self.initial_focus = self.body(body)
  60         body.pack(padx=5, pady=5)
  61
  62         self.buttonbox()
  63
  64         self.grab_set()
  65
  66         if not self.initial_focus:
  67             self.initial_focus = self
  68
  69         self.protocol("WM_DELETE_WINDOW", self.cancel)
  70
  71         self.geometry("+%d+%d" % (parent.winfo_rootx()+50,
  72                                   parent.winfo_rooty()+50))
  73
  74         self.initial_focus.focus_set()
  75
  76         self.wait_window(self)
  77
  78     def destroy(self):
  79         '''Destroy the window'''
  80         self.initial_focus = None
  81         Toplevel.destroy(self)
  82
  83     #
  84     # construction hooks
  85
  86     def body(self, master):
  87         '''create dialog body.
  88
  89         return widget that should have initial focus.
  90         This method should be overridden, and is called
  91         by the __init__ method.
  92         '''
  93         pass
  94
  95     def buttonbox(self):
  96         '''add standard button box.
  97
  98         override if you don't want the standard buttons
  99         '''
 100
 101         box = Frame(self)
 102
 103         w = Button(box, text="OK", width=10, command=self.ok, default=ACTIVE)
 104         w.pack(side=LEFT, padx=5, pady=5)
 105         w = Button(box, text="Cancel", width=10, command=self.cancel)
 106         w.pack(side=LEFT, padx=5, pady=5)
 107
 108         self.bind("<Return>", self.ok)
 109         self.bind("<Escape>", self.cancel)
 110
 111         box.pack()
 112
 113     #
 114     # standard button semantics
 115
 116     def ok(self, event=None):
 117
 118         if not self.validate():
 119             self.initial_focus.focus_set() # put focus back
 120             return
 121
 122         self.withdraw()
 123         self.update_idletasks()
 124
 125         self.apply()
 126
 127         self.cancel()
 128
 129     def cancel(self, event=None):
 130
 131         # put focus back to the parent window
 132         self.parent.focus_set()
 133         self.destroy()
 134
 135     #
 136     # command hooks
 137
 138     def validate(self):
 139         '''validate the data
 140
 141         This method is called automatically to validate the data before the
 142         dialog is destroyed. By default, it always validates OK.
 143         '''
 144
 145         return 1 # override
 146
 147     def apply(self):
 148         '''process the data
 149
 150         This method is called automatically to process the data, *after*
 151         the dialog is destroyed. By default, it does nothing.
 152         '''
 153
 154         pass # override
 155
 156
 157 # --------------------------------------------------------------------
 158 # convenience dialogues
 159
 160 import string
 161
 162 class _QueryDialog(Dialog):
 163
 164     def __init__(self, title, prompt,
 165                  initialvalue=None,
 166                  minvalue = None, maxvalue = None,
 167                  parent = None):
 168
 169         if not parent:
 170             import Tkinter
 171             parent = Tkinter._default_root
 172
 173         self.prompt   = prompt
 174         self.minvalue = minvalue
 175         self.maxvalue = maxvalue
 176
 177         self.initialvalue = initialvalue
 178
 179         Dialog.__init__(self, parent, title)
 180
 181     def destroy(self):
 182         self.entry = None
 183         Dialog.destroy(self)
 184
 185     def body(self, master):
 186
 187         w = Label(master, text=self.prompt, justify=LEFT)
 188         w.grid(row=0, padx=5, sticky=W)
 189
 190         self.entry = Entry(master, name="entry")
 191         self.entry.grid(row=1, padx=5, sticky=W+E)
 192
 193         if self.initialvalue:
 194             self.entry.insert(0, self.initialvalue)
 195             self.entry.select_range(0, END)
 196
 197         return self.entry
 198
 199     def validate(self):
 200
 201         import tkMessageBox
 202
 203         try:
 204             result = self.getresult()
 205         except ValueError:
 206             tkMessageBox.showwarning(
 207                 "Illegal value",
 208                 self.errormessage + "\nPlease try again",
 209                 parent = self
 210             )
 211             return 0
 212
 213         if self.minvalue is not None and result < self.minvalue:
 214             tkMessageBox.showwarning(
 215                 "Too small",
 216                 "The allowed minimum value is %s. "
 217                 "Please try again." % self.minvalue,
 218                 parent = self
 219             )
 220             return 0
 221
 222         if self.maxvalue is not None and result > self.maxvalue:
 223             tkMessageBox.showwarning(
 224                 "Too large",
 225                 "The allowed maximum value is %s. "
 226                 "Please try again." % self.maxvalue,
 227                 parent = self
 228             )
 229             return 0
 230
 231         self.result = result
 232
 233         return 1
 234
 235
 236 class _QueryInteger(_QueryDialog):
 237     errormessage = "Not an integer."
 238     def getresult(self):
 239         return string.atoi(self.entry.get())
 240
 241 def askinteger(title, prompt, **kw):
 242     '''get an integer from the user
 243
 244     Arguments:
 245
 246         title -- the dialog title
 247         prompt -- the label text
 248         **kw -- see SimpleDialog class
 249
 250     Return value is an integer
 251     '''
 252     d = apply(_QueryInteger, (title, prompt), kw)
 253     return d.result
 254
 255 class _QueryFloat(_QueryDialog):
 256     errormessage = "Not a floating point value."
 257     def getresult(self):
 258         return string.atof(self.entry.get())
 259
 260 def askfloat(title, prompt, **kw):
 261     '''get a float from the user
 262
 263     Arguments:
 264
 265         title -- the dialog title
 266         prompt -- the label text
 267         **kw -- see SimpleDialog class
 268
 269     Return value is a float
 270     '''
 271     d = apply(_QueryFloat, (title, prompt), kw)
 272     return d.result
 273
 274 class _QueryString(_QueryDialog):
 275     def getresult(self):
 276         return self.entry.get()
 277
 278 def askstring(title, prompt, **kw):
 279     '''get a string from the user
 280
 281     Arguments:
 282
 283         title -- the dialog title
 284         prompt -- the label text
 285         **kw -- see SimpleDialog class
 286
 287     Return value is a string
 288     '''
 289     d = apply(_QueryString, (title, prompt), kw)
 290     return d.result
 291
 292 if __name__ == "__main__":
 293
 294     root = Tk()
 295     root.update()
 296
 297     print askinteger("Spam", "Egg count", initialvalue=12*12)
 298     print askfloat("Spam", "Egg weight\n(in tons)", minvalue=1, maxvalue=100)
 299     print askstring("Spam", "Egg label")
 300