Pmw/Pmw_1_2/lib/PmwComboBox.py

   1 # Based on iwidgets2.2.0/combobox.itk code.
   2
   3 import os
   4 import string
   5 import types
   6 import Tkinter
   7 import Pmw
   8
   9 class ComboBox(Pmw.MegaWidget):
  10     def __init__(self, parent = None, **kw):
  11
  12         # Define the megawidget options.
  13         INITOPT = Pmw.INITOPT
  14         optiondefs = (
  15             ('autoclear',          0,          INITOPT),
  16             ('buttonaspect',       1.0,        INITOPT),
  17             ('dropdown',           1,          INITOPT),
  18             ('fliparrow',          0,          INITOPT),
  19             ('history',            1,          INITOPT),
  20             ('labelmargin',        0,          INITOPT),
  21             ('labelpos',           None,       INITOPT),
  22             ('listheight',         200,        INITOPT),
  23             ('selectioncommand',   None,       None),
  24             ('sticky',            'ew',        INITOPT),
  25             ('unique',             1,          INITOPT),
  26         )
  27         self.defineoptions(kw, optiondefs)
  28
  29         # Initialise the base class (after defining the options).
  30         Pmw.MegaWidget.__init__(self, parent)
  31
  32         # Create the components.
  33         interior = self.interior()
  34
  35         self._entryfield = self.createcomponent('entryfield',
  36                 (('entry', 'entryfield_entry'),), None,
  37                 Pmw.EntryField, (interior,))
  38         self._entryfield.grid(column=2, row=2, sticky=self['sticky'])
  39         interior.grid_columnconfigure(2, weight = 1)
  40         self._entryWidget = self._entryfield.component('entry')
  41
  42         if self['dropdown']:
  43             self._isPosted = 0
  44             interior.grid_rowconfigure(2, weight = 1)
  45
  46             # Create the arrow button.
  47             self._arrowBtn = self.createcomponent('arrowbutton',
  48                     (), None,
  49                     Tkinter.Canvas, (interior,), borderwidth = 2,
  50                     relief = 'raised',
  51                     width = 16, height = 16)
  52             if 'n' in self['sticky']:
  53                 sticky = 'n'
  54             else:
  55                 sticky = ''
  56             if 's' in self['sticky']:
  57                 sticky = sticky + 's'
  58             self._arrowBtn.grid(column=3, row=2, sticky = sticky)
  59             self._arrowRelief = self._arrowBtn.cget('relief')
  60
  61             # Create the label.
  62             self.createlabel(interior, childCols=2)
  63
  64             # Create the dropdown window.
  65             self._popup = self.createcomponent('popup',
  66                     (), None,
  67                     Tkinter.Toplevel, (interior,))
  68             self._popup.withdraw()
  69             self._popup.overrideredirect(1)
  70
  71             # Create the scrolled listbox inside the dropdown window.
  72             self._list = self.createcomponent('scrolledlist',
  73                     (('listbox', 'scrolledlist_listbox'),), None,
  74                     Pmw.ScrolledListBox, (self._popup,),
  75                     hull_borderwidth = 2,
  76                     hull_relief = 'raised',
  77                     hull_height = self['listheight'],
  78                     usehullsize = 1,
  79                     listbox_exportselection = 0)
  80             self._list.pack(expand=1, fill='both')
  81             self.__listbox = self._list.component('listbox')
  82
  83             # Bind events to the arrow button.
  84             self._arrowBtn.bind('<1>', self._postList)
  85             self._arrowBtn.bind('<Configure>', self._drawArrow)
  86             self._arrowBtn.bind('<3>', self._next)
  87             self._arrowBtn.bind('<Shift-3>', self._previous)
  88             self._arrowBtn.bind('<Down>', self._next)
  89             self._arrowBtn.bind('<Up>', self._previous)
  90             self._arrowBtn.bind('<Control-n>', self._next)
  91             self._arrowBtn.bind('<Control-p>', self._previous)
  92             self._arrowBtn.bind('<Shift-Down>', self._postList)
  93             self._arrowBtn.bind('<Shift-Up>', self._postList)
  94             self._arrowBtn.bind('<F34>', self._postList)
  95             self._arrowBtn.bind('<F28>', self._postList)
  96             self._arrowBtn.bind('<space>', self._postList)
  97
  98             # Bind events to the dropdown window.
  99             self._popup.bind('<Escape>', self._unpostList)
 100             self._popup.bind('<space>', self._selectUnpost)
 101             self._popup.bind('<Return>', self._selectUnpost)
 102             self._popup.bind('<ButtonRelease-1>', self._dropdownBtnRelease)
 103             self._popup.bind('<ButtonPress-1>', self._unpostOnNextRelease)
 104
 105             # Bind events to the Tk listbox.
 106             self.__listbox.bind('<Enter>', self._unpostOnNextRelease)
 107
 108             # Bind events to the Tk entry widget.
 109             self._entryWidget.bind('<Configure>', self._resizeArrow)
 110             self._entryWidget.bind('<Shift-Down>', self._postList)
 111             self._entryWidget.bind('<Shift-Up>', self._postList)
 112             self._entryWidget.bind('<F34>', self._postList)
 113             self._entryWidget.bind('<F28>', self._postList)
 114
 115             # Need to unpost the popup if the entryfield is unmapped (eg:
 116             # its toplevel window is withdrawn) while the popup list is
 117             # displayed.
 118             self._entryWidget.bind('<Unmap>', self._unpostList)
 119
 120         else:
 121             # Create the scrolled listbox below the entry field.
 122             self._list = self.createcomponent('scrolledlist',
 123                     (('listbox', 'scrolledlist_listbox'),), None,
 124                     Pmw.ScrolledListBox, (interior,),
 125                     selectioncommand = self._selectCmd)
 126             self._list.grid(column=2, row=3, sticky='nsew')
 127             self.__listbox = self._list.component('listbox')
 128
 129             # The scrolled listbox should expand vertically.
 130             interior.grid_rowconfigure(3, weight = 1)
 131
 132             # Create the label.
 133             self.createlabel(interior, childRows=2)
 134
 135         self._entryWidget.bind('<Down>', self._next)
 136         self._entryWidget.bind('<Up>', self._previous)
 137         self._entryWidget.bind('<Control-n>', self._next)
 138         self._entryWidget.bind('<Control-p>', self._previous)
 139         self.__listbox.bind('<Control-n>', self._next)
 140         self.__listbox.bind('<Control-p>', self._previous)
 141
 142         if self['history']:
 143             self._entryfield.configure(command=self._addHistory)
 144
 145         # Check keywords and initialise options.
 146         self.initialiseoptions()
 147
 148     def destroy(self):
 149         if self['dropdown'] and self._isPosted:
 150             Pmw.popgrab(self._popup)
 151         Pmw.MegaWidget.destroy(self)
 152
 153     #======================================================================
 154
 155     # Public methods
 156
 157     def get(self, first = None, last=None):
 158         if first is None:
 159             return self._entryWidget.get()
 160         else:
 161             return self._list.get(first, last)
 162
 163     def invoke(self):
 164         if self['dropdown']:
 165             self._postList()
 166         else:
 167             return self._selectCmd()
 168
 169     def selectitem(self, index, setentry=1):
 170         if type(index) == types.StringType:
 171             text = index
 172             items = self._list.get(0, 'end')
 173             if text in items:
 174                 index = list(items).index(text)
 175             else:
 176                 raise IndexError, 'index "%s" not found' % text
 177         elif setentry:
 178             text = self._list.get(0, 'end')[index]
 179
 180         self._list.select_clear(0, 'end')
 181         self._list.select_set(index, index)
 182         self._list.activate(index)
 183         self.see(index)
 184         if setentry:
 185             self._entryfield.setentry(text)
 186
 187     # Need to explicitly forward this to override the stupid
 188     # (grid_)size method inherited from Tkinter.Frame.Grid.
 189     def size(self):
 190         return self._list.size()
 191
 192     # Need to explicitly forward this to override the stupid
 193     # (grid_)bbox method inherited from Tkinter.Frame.Grid.
 194     def bbox(self, index):
 195         return self._list.bbox(index)
 196
 197     def clear(self):
 198         self._entryfield.clear()
 199         self._list.clear()
 200
 201     #======================================================================
 202
 203     # Private methods for both dropdown and simple comboboxes.
 204
 205     def _addHistory(self):
 206         input = self._entryWidget.get()
 207
 208         if input != '':
 209             index = None
 210             if self['unique']:
 211                 # If item is already in list, select it and return.
 212                 items = self._list.get(0, 'end')
 213                 if input in items:
 214                     index = list(items).index(input)
 215
 216             if index is None:
 217                 index = self._list.index('end')
 218                 self._list.insert('end', input)
 219
 220             self.selectitem(index)
 221             if self['autoclear']:
 222                 self._entryWidget.delete(0, 'end')
 223
 224             # Execute the selectioncommand on the new entry.
 225             self._selectCmd()
 226
 227     def _next(self, event):
 228         size = self.size()
 229         if size <= 1:
 230             return
 231
 232         cursels = self.curselection()
 233
 234         if len(cursels) == 0:
 235             index = 0
 236         else:
 237             index = string.atoi(cursels[0])
 238             if index == size - 1:
 239                 index = 0
 240             else:
 241                 index = index + 1
 242
 243         self.selectitem(index)
 244
 245     def _previous(self, event):
 246         size = self.size()
 247         if size <= 1:
 248             return
 249
 250         cursels = self.curselection()
 251
 252         if len(cursels) == 0:
 253             index = size - 1
 254         else:
 255             index = string.atoi(cursels[0])
 256             if index == 0:
 257                 index = size - 1
 258             else:
 259                 index = index - 1
 260
 261         self.selectitem(index)
 262
 263     def _selectCmd(self, event=None):
 264
 265         sels = self.getcurselection()
 266         if len(sels) == 0:
 267             item = None
 268         else:
 269             item = sels[0]
 270             self._entryfield.setentry(item)
 271
 272         cmd = self['selectioncommand']
 273         if callable(cmd):
 274             if event is None:
 275                 # Return result of selectioncommand for invoke() method.
 276                 return cmd(item)
 277             else:
 278                 cmd(item)
 279
 280     #======================================================================
 281
 282     # Private methods for dropdown combobox.
 283
 284     def _drawArrow(self, event=None, sunken=0):
 285         arrow = self._arrowBtn
 286         if sunken:
 287             self._arrowRelief = arrow.cget('relief')
 288             arrow.configure(relief = 'sunken')
 289         else:
 290             arrow.configure(relief = self._arrowRelief)
 291
 292         if self._isPosted and self['fliparrow']:
 293             direction = 'up'
 294         else:
 295             direction = 'down'
 296         Pmw.drawarrow(arrow, self['entry_foreground'], direction, 'arrow')
 297
 298     def _postList(self, event = None):
 299         self._isPosted = 1
 300         self._drawArrow(sunken=1)
 301
 302         # Make sure that the arrow is displayed sunken.
 303         self.update_idletasks()
 304
 305         x = self._entryfield.winfo_rootx()
 306         y = self._entryfield.winfo_rooty() + \
 307             self._entryfield.winfo_height()
 308         w = self._entryfield.winfo_width() + self._arrowBtn.winfo_width()
 309         h =  self.__listbox.winfo_height()
 310         sh = self.winfo_screenheight()
 311
 312         if y + h > sh and y > sh / 2:
 313             y = self._entryfield.winfo_rooty() - h
 314
 315         self._list.configure(hull_width=w)
 316
 317         Pmw.setgeometryanddeiconify(self._popup, '+%d+%d' % (x, y))
 318
 319         # Grab the popup, so that all events are delivered to it, and
 320         # set focus to the listbox, to make keyboard navigation
 321         # easier.
 322         Pmw.pushgrab(self._popup, 1, self._unpostList)
 323         self.__listbox.focus_set()
 324
 325         self._drawArrow()
 326
 327         # Ignore the first release of the mouse button after posting the
 328         # dropdown list, unless the mouse enters the dropdown list.
 329         self._ignoreRelease = 1
 330
 331     def _dropdownBtnRelease(self, event):
 332         if (event.widget == self._list.component('vertscrollbar') or
 333                 event.widget == self._list.component('horizscrollbar')):
 334             return
 335
 336         if self._ignoreRelease:
 337             self._unpostOnNextRelease()
 338             return
 339
 340         self._unpostList()
 341
 342         if (event.x >= 0 and event.x < self.__listbox.winfo_width() and
 343                 event.y >= 0 and event.y < self.__listbox.winfo_height()):
 344             self._selectCmd()
 345
 346     def _unpostOnNextRelease(self, event = None):
 347         self._ignoreRelease = 0
 348
 349     def _resizeArrow(self, event):
 350         bw = (string.atoi(self._arrowBtn['borderwidth']) +
 351                 string.atoi(self._arrowBtn['highlightthickness']))
 352         newHeight = self._entryfield.winfo_reqheight() - 2 * bw
 353         newWidth = int(newHeight * self['buttonaspect'])
 354         self._arrowBtn.configure(width=newWidth, height=newHeight)
 355         self._drawArrow()
 356
 357     def _unpostList(self, event=None):
 358         if not self._isPosted:
 359             # It is possible to get events on an unposted popup.  For
 360             # example, by repeatedly pressing the space key to post
 361             # and unpost the popup.  The <space> event may be
 362             # delivered to the popup window even though
 363             # Pmw.popgrab() has set the focus away from the
 364             # popup window.  (Bug in Tk?)
 365             return
 366
 367         # Restore the focus before withdrawing the window, since
 368         # otherwise the window manager may take the focus away so we
 369         # can't redirect it.  Also, return the grab to the next active
 370         # window in the stack, if any.
 371         Pmw.popgrab(self._popup)
 372         self._popup.withdraw()
 373
 374         self._isPosted = 0
 375         self._drawArrow()
 376
 377     def _selectUnpost(self, event):
 378         self._unpostList()
 379         self._selectCmd()
 380
 381 Pmw.forwardmethods(ComboBox, Pmw.ScrolledListBox, '_list')
 382 Pmw.forwardmethods(ComboBox, Pmw.EntryField, '_entryfield')