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         if self.parent is not None:
  72             self.geometry("+%d+%d" % (parent.winfo_rootx()+50,
  73                                       parent.winfo_rooty()+50))
  74
  75         self.initial_focus.focus_set()
  76
  77         self.wait_window(self)
  78
  79     def destroy(self):
  80         '''Destroy the window'''
  81         self.initial_focus = None
  82         Toplevel.destroy(self)
  83
  84     #
  85     # construction hooks
  86
  87     def body(self, master):
  88         '''create dialog body.
  89
  90         return widget that should have initial focus.
  91         This method should be overridden, and is called
  92         by the __init__ method.
  93         '''
  94         pass
  95
  96     def buttonbox(self):
  97         '''add standard button box.
  98
  99         override if you do not want the standard buttons
 100         '''
 101
 102         box = Frame(self)
 103
 104         w = Button(box, text="OK", width=10, command=self.ok, default=ACTIVE)
 105         w.pack(side=LEFT, padx=5, pady=5)
 106         w = Button(box, text="Cancel", width=10, command=self.cancel)
 107         w.pack(side=LEFT, padx=5, pady=5)
 108
 109         self.bind("<Return>", self.ok)
 110         self.bind("<Escape>", self.cancel)
 111
 112         box.pack()
 113
 114     #
 115     # standard button semantics
 116
 117     def ok(self, event=None):
 118
 119         if not self.validate():
 120             self.initial_focus.focus_set() # put focus back
 121             return
 122
 123         self.withdraw()
 124         self.update_idletasks()
 125
 126         self.apply()
 127
 128         self.cancel()
 129
 130     def cancel(self, event=None):
 131
 132         # put focus back to the parent window
 133         if self.parent is not None:
 134             self.parent.focus_set()
 135         self.destroy()
 136
 137     #
 138     # command hooks
 139
 140     def validate(self):
 141         '''validate the data
 142
 143         This method is called automatically to validate the data before the
 144         dialog is destroyed. By default, it always validates OK.
 145         '''
 146
 147         return 1 # override
 148
 149     def apply(self):
 150         '''process the data
 151
 152         This method is called automatically to process the data, *after*
 153         the dialog is destroyed. By default, it does nothing.
 154         '''
 155
 156         pass # override
 157
 158
 159 # --------------------------------------------------------------------
 160 # convenience dialogues
 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 int(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 float(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 __init__(self, *args, **kw):
 276         if kw.has_key("show"):
 277             self.__show = kw["show"]
 278             del kw["show"]
 279         else:
 280             self.__show = None
 281         _QueryDialog.__init__(self, *args, **kw)
 282
 283     def body(self, master):
 284         entry = _QueryDialog.body(self, master)
 285         if self.__show is not None:
 286             entry.configure(show=self.__show)
 287         return entry
 288
 289     def getresult(self):
 290         return self.entry.get()
 291
 292 def askstring(title, prompt, **kw):
 293     '''get a string from the user
 294
 295     Arguments:
 296
 297         title -- the dialog title
 298         prompt -- the label text
 299         **kw -- see SimpleDialog class
 300
 301     Return value is a string
 302     '''
 303     d = apply(_QueryString, (title, prompt), kw)
 304     return d.result
 305
 306 if __name__ == "__main__":
 307
 308     root = Tk()
 309     root.update()
 310
 311     print askinteger("Spam", "Egg count", initialvalue=12*12)
 312     print askfloat("Spam", "Egg weight\n(in tons)", minvalue=1, maxvalue=100)
 313     print askstring("Spam", "Egg label")