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1. Summary

First Beta, guarantted to be loaded with bugs!

This demo creates a widget with full "styled text editing" capabilities; sort of a mini-word processor. It runs "as is" on my WinXP machine with Python 2.5. The demo allows styling of any selected text via toolbars; just select the text, then select the styling. (Currently, it's not possible to select insertion styling). Also included are buttons to save and retrieve all content and styling information (works for the small tests I've tried myself, however, expect bugs!).

There are actualy three widgets created: StyledText (which contains my desired API), ?TextWriter (A StyledText object with toolbars all thrown into a Frame, and ?StyleEditor (A dialog box for allowing the user to create custom styles). StyledText widget subclasses the Text widget to give greater freedom in the assignment of any single styling attribute to any region. This differs from the Text widget in that the Text widget does not allow you to assign a family, size, weight or slant with tag_config(). That is, for example, you can't simply apply 'bold' to some region of text.

This demo was written quite quickly (I pounded it out over the weekend) so I'm sure it's full of bugs and may not be entirely tk-like. Future versions will strive to increase functionality, reduce bugs and make the widget more tk-like. Suggestions for imporvements are more than welcome.

2. API Notes

applyStyleAttribute( index1, index2, attributeName, attributeValue )

This method is the frontend to the business. attributeName and attributeValue may be any option accpeted by tag_config() of the Text widget along with appropriate value. There are also some new options:

Several previously existing options have some new values:

3. Implementation Details

--- These notes assume you understand the basics of using the text widget. --

To make the widget react more naturally when changing the value of 'offset' across a region, I found it convenient to make 'offset' A sub-option of the font object rather than a full option. In this way if we have some text which has (Ariel, 12, bold, superscript), the original size is preserved in the font. The actual tag in the text widget gets configured with  {font:('Ariel',5,bold), offset='10p'} . Now if the user decides to remove the superscript styling, the information of the original size (12) is still available in the font object so it's easily restored. To implement this I defined my own class Font to use with the StyledText in place of tkFont. This class includes the very useful method tagOptions() which returns a dictionary of options suitable for passing to Text's tag_config() to produce the desired appearance. class Font manages the options: family, size, weight, slant and offset. Underline and Overstrike can be set independently via tag_config(), so they are not managed by Font.

The primary attribute styling class is class Style. This class is a subclass of dict which is intended to hold values for all the style options not part of ?StylerFont. class Style also contains a _font member and like, ?StylerFont, has the very useful tagOptions() method. This tagOptions will combine its own values with any it gets from calling tagOptions() on _font to form a complete set of values suitable for tag_config().

To simplify the seeming chaos of layered tags and overlapping tagged regions, I decided to first define some restrictions on how tags can be used.

  1. The widget has a default styling (which assignes a value to every style attribute).
  2. A non-?StylerFont tag may configure exactly one styling attribute.
  3. For any index in the underlying text widget, there may be at most one tag for any given non-?StylerFont attribute.
  4. For any index in the underlying text widget, there may be at most one tag handling a ?StylerFont.
  5. For any unique attribute configuration in use there should exist exactly one tag.

These restrictions eliminate "Infinite depth tag stack" (criteria 2, 3 & 4) and "tagName redundancy" (criteria 5). Conceptually we now have just two styling layers: default styling on the bottom, custom styling on top. So, for example if I call applyStyleAttribute( begin, end, 'underline', Tkinter.TRUE ), any existing tags in the region (begin,end) which assign to 'underline', are first deleted if the new styling is something other than the default for the attribute being set, the new styling is applied.

With the tag chaos of the Text widget under control, it's now possible to design an algorithm which provides applyStyleAttribute() with a "map" of the current styling of the region in question. This map actually splits the region at every point that any tag in the region begins or ends (as well as the endpoints of the region itself). Here's an example to illustrate:

Sample Text:        Sample text to illustrate a styling map of a region of text.
Indecies:                     1         2         3         4         5         6
                    0123456789012345678901234567890123456789012345678901234567890

tag1:                    |<---------------->|          |<--------------->|
tag2:                              |<----------->|

Region to map:       |<-------------------------------------->|
Resulting map:       |<->|<------->|<------>|<-->|<--->|<---->|

So here we have some Sample Text. tag1 spans regions 1.5 - 1.24 and 1.35 - 1.53, and tag2 spans 1.15 - 1.29. mapRegion() slices at any tag begin or tag end and at its endpoints this results in a map with six segments. For each segment in the map, the list of active tags is also given. So mapRegion() in the above example returns the following list:
[
   ( '1.1',  '1.5',  [ ] ),                 # No tags in this region
   ( '1.5',  '1.15', [ 'tag1' ] ),          # tag1-bold in this region
   ( '1.15', '1.24', [ 'tag1', 'tag2' ] ),  # etc.
   ( '1.24', '1.29', [ 'tag2' ] ),
   ( '1.29', '1.35', [ ] ),
   ( '1.35', '1.42', [ 'tag1' ] )
]

Next is to determine which attributes and values are set in each subregion. The obvious way is to have a dict mapping tagName, to Style object, but it's not the only way. We need to avoid tag-name redundancy, criterion 5 (E.g. We don't want to define a new tag for underline every time the user selects a bit of text and applies the underline style. We should use the same underline tag for all cases of underline). To handle this I use a standard naming convention for tags such that the name of the tag encodes the tag's configuration - this is reasonable because of criterion 2 (the names won't get too long). This also eliminates the need for a dictionary since the name of each tag can be decoded to get its configuration. Any tag which sets a ?StylerFont attribute (family, size, weight, slant or offset) has the tag named ast: "-font-%(family)s-%(size)d-%(weight)s-%(slant)s-%(offset)". The remaining attributes have tags named as: "-attribute-%(attributeName)s-%(attributeValue)s".

Now if applyStyleAttribute() gets an assignment to any ?StylerFont attribute, it iterates throught the subregions returned by mapRegion() if it there's a tag that begins "-font-..." (and there can be only one per criterion 3), then it asks ?StylerFont to decode the tag name and create a new ?StylerFont instance, then it deletes the tag from the text widget. Next it call's ?StylerFont's deriveFont(attributeName,newAttributeValue) which returns a new ?StylerFont instance. It calls tagOptions() and fontName() on the new font object to get what's needed to define and configure a new "-font-..." tag for the subregion.

Similarly, if applyStyleAttribute() gets an assignment to any other attribute, it iterates through the subregions returned by mapRegion(), if there's a tag that begins "-attribute-%(attributeName)s-" (and there can be only one per criterion 4), then it decodes the tag name the tag is deleted from the subregion in the underlying text widget, a new tag name and Style instance is creatd which are used to define and configure the new tag in the underlying text widget.

In that cases where applyStyleAttribute() is iterating over the subregions returned by mapRegion, and the subregion is empty or does not contain any styling on attributeName, then applyStyleAttribute assumes the default styling (criterion 1).

The code follows:

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import Tix as Tk
import tkFont as Font

DIALOG_FONT       = 'Times 8'
DEFAULT_TEXT_FONT = ('Lucida Sans Unicode', 12)

class ImageFactory( object ):
   _images = { }

   @staticmethod
   def makeImage( filename ):
      if filename not in ImageFactory._images:
         ImageFactory._images[ filename ] = Tk.PhotoImage( file=filename )

      return ImageFactory._images[ filename ]


class StylerFont( object ):
   FIELD_NAMES          = [ 'family', 'size', 'weight', 'slant', 'offset', 'bold', 'italic' ]
   FONT_TAG_FORMAT      = '-font-%(family)s-%(size)d-%(weight)s-%(slant)s-%(offset)s'
   FONT_TAG_PREFIX      = '-font-'
   FONT_LIBRARY         = { }
   DEFAULT_FONT         = None

   def __init__( self, fontOpts ):
      self._fontOpts = fontOpts

   def __setitem__( self, key, value ):
      if key == 'bold':
         self._fontOpts[ 'weight' ] = 'bold' if value else 'normal'
      elif key == 'italic':
         self._fontOpts[ 'slant'  ] = 'italic' if value else 'roman'
      else:
         self._fontOpts[ key ] = value

   def __getitem__( self, key ):
      if key == 'bold':
         return self._fontOpts[ 'weight' ] == 'bold'
      elif key == 'italic':
         return self._fontOpts[ 'slant' ] == 'italic'
      else:
         return self._fontOpts[ key ]

   def fontName( self ):
      return StylerFont.FONT_TAG_FORMAT % self._fontOpts

   def fontOptions( self ):
      return self._fontOpts

   def tagOptions( self ):
      options = { }

      styleList = [ ]
      if self._fontOpts['weight'] == 'bold':
         styleList.append( 'bold' )
      if self._fontOpts['slant'] == 'italic':
         styleList.append( 'italic' )

      if self._fontOpts['offset'] != 'normal':
         # If the region includes an offset, we need to reestablish that
         baseSize = self._fontOpts['size']
         size = int(baseSize * (3.0 / 5.0) + 0.5)

         if self._fontOpts['offset'] == 'superscript':
            options[ 'offset' ] = '%dp'  % int(baseSize / 2.0 + 0.5)
         else:
            options[ 'offset' ] = '-%dp' % int(baseSize / 5.0 + 0.5)
      else:
         size = self._fontOpts['size']

      options[ 'font' ] = ( self._fontOpts['family'], size, ' '.join(styleList) )

      return options

   def deriveFont( self, **newOpts ):
      newFont = copy.deepcopy( self )
      for key,val in newOpts.iteritems():
         newFont[ key ] = val

      fontName = newFont.fontName( )

      if fontName not in StylerFont.FONT_LIBRARY:
         StylerFont.FONT_LIBRARY[ fontName ] = newFont
      return StylerFont.FONT_LIBRARY[ fontName ]

   def tkFont( self ):
      return Font.Font( family=self._fontOpts['family'], size=self._fontOpts['size'], weight=self._fontOpts['weight'], slant=self._fontOpts['slant'] )

   @staticmethod
   def setup( aTextWidget ):
      StylerFont.DEFAULT_FONT = StylerFont.getFont( aTextWidget['font'] )
      StylerFont.FONT_LIBRARY[ 'default' ] = StylerFont.DEFAULT_FONT

   @staticmethod
   def getFont( aFontSpec=None, **options ):
      fontOpts = { }
      fontStyling = ''

      if aFontSpec:
         if isinstance( aFontSpec, (str,unicode) ):
            if aFontSpec == 'default':
               return StylerFont.FONT_LIBRARY[ 'default' ]
            elif aFontSpec.startswith( StylerFont.FONT_TAG_PREFIX ):
               # We have a font name
               try:
                  return StylerFont.FONT_LIBRARY[ aFontSpec ]
               except:
                  for key,val in zip( ['family','size','weight','slant','offset'], aFontSpec.split( '-' )[2:] ):
                     fontOpts[ key ] = val
                  fontOpts['size'] = int(fontOpts['size'])
                  StylerFont.FONT_LIBRARY[ aFontSpec ] = StylerFont( fontOpts )
                  return StylerFont.FONT_LIBRARY[ aFontSpec ]
            else:
               # We need to try to decode a tkinter font string
               if aFontSpec[0] == '{':
                  fontFamilyStringBegin = 1
                  fontFamilyStringEnd    = aFontSpec.find( '}' )
                  fontSize, sep, fontStyling = aFontSpec[ fontFamilyStringEnd + 2 : ].lower().partition( ' ' )
               else:
                  fontFamilyStringBegin = 0
                  fontFamilyStringEnd   = aFontSpec.find( ' ' )
                  fontSize, sep, fontStyling = aFontSpec[ fontFamilyStringEnd + 1 : ].lower().partition( ' ' )

               fontOpts['family'    ] = aFontSpec[ fontFamilyStringBegin : fontFamilyStringEnd ]
               fontOpts['size'      ] = int(fontSize)

         elif isinstance( aFontSpec, (list,tuple) ):
            # We need to decode a tkinter font tuple
            fontStyling = aFontSpec[2] if len(aFontSpec)==3 else ''
            fontOpts['family'    ] = aFontSpec[0]
            fontOpts['size'      ] = aFontSpec[1]

      elif options:
         if 'family' in options:
            if 'bold' in options:
               options[ 'weight' ] = 'bold' if options['bold'] else 'normal'
               del options[ 'bold' ]

            if 'italic' in options:
               options[ 'slant' ] = 'italic' if options['italic'] else 'roman'
               del options[ 'italic' ]

            fontName = StylerFont.FONT_TAG_FORMAT % options

            try:
               return StylerFont.FONT_LIBRARY[ fontName ]
            except:
               StylerFont.FONT_LIBRARY[ fontName ] = StylerFont( options )
               return StylerFont.FONT_LIBRARY[ fontName ]

         else:
            fontTuple = options[ 'font' ]

            fontStyling = aFontSpec[2] if len(aFontSpec)==3 else ''
            fontOpts['family'    ] = fontTuple[0]
            fontOpts['size'      ] = fontTuple[1]

      else:
         return StylerFont.getFont( 'default' )

      fontOpts['weight'    ] = 'bold' if 'bold' in fontStyling else 'normal'
      fontOpts['slant'     ] = 'italic' if 'italic' in fontStyling else 'roman'
      fontOpts['underline' ] = False
      fontOpts['overstrike'] = False
      fontOpts['offset'    ] = 'normal'

      fontName = StylerFont.FONT_TAG_FORMAT % fontOpts

      try:
         return StylerFont.FONT_LIBRARY[ fontName ]
      except:
         theFontObj = StylerFont( fontOpts )
         StylerFont.FONT_LIBRARY[ fontName ] = theFontObj
         return theFontObj


class Style( dict ):
   FIELD_NAMES      = [ 'font', 'underline', 'overstrike', 'foreground', 'background' 'fgstipple', 'bgstipple', 'borderwidth', 'relief',
                        'justify', 'wrap', 'lmargin1', 'lmargin2', 'rmargin', 'spacing1', 'spacing2', 'spacing3', 'tabs' ]
   ATTRIBUTE_TAG_FORMAT  = '-attribute-%(name)s-%(value)s'
   ATTRIBUTE_TAG_PREFIX  = '-attribute-'
   DEFAULT_STYLE    =  None
   OFF_VALUES       =  { }

   '''Most fields have the exact same set of possible values as the related option for the text widget.
   'font' is a legitimate Style field.  While any subfield of 'font' is not a style field of Style,
   they are accepted by __init__, __setitem__ and __getitem__ but will simply be passed to the
   StylerFont subobject.  (e.g. family, may be requested of a style instance and will be passed to the
   StylerFont object).
   
   The 'offset' and the three 'spacing' options can take any of the usual values available to the text
   widget. However, several new values are also possible for these fields.
   
   font:          StylerFont
      family:     string.    A font family name
      size:       int.       A font size in points
      weight:     string.    One of:  'normal', 'bold'
      bold:       boolean.   An alternate for weight
      slant:      string.    One of:  'roman', 'italic'
      italic:     boolean.   An alternate for slant
      underline:  boolean.
      overstrike: boolean.
      offset:     Dimension or string.  One of: 'normal', 'subscript', 'superscript'
   
   foreground:    Color.
   background:    Color.
   fgstipple:     bitmap.
   bgstipple:     bitmap.
   borderwidth:   Dimension.
   relief:        string.    One of: 'flat', 'sunken', 'raised', 'groove', 'ridge', 'solid', ''
   
   justify:       string.    One of: 'left', 'right', 'center', ''
   wrap:          string.    One of: 'none', 'char', 'word', ''
   lmargin1:      Dimension.
   lmargin2:      Dimension.
   rmargin:       Dimension.
   spacing1:      Dimension or string.  One of: 'None', 'Half Line', 'One Line', 'Two Lines'
   spacing2:      Dimension or string.  One of: 'None', 'Half Line', 'One Line', 'Two Lines'
   spacing3:      Dimension or string.  One of: 'None', 'Half Line', 'One Line', 'Two Lines'
   tabs:          string of Dimension.
   '''
   def __init__( self, **options ):
      dict.__init__( self )
      self._font = None

      for key,value in options.iteritems( ):
         if key == 'font':
            if isinstance( value, StylerFont ):
               self._font = value
            else:
               self._font = StylerFont( value )
         else:
            dict.__setitem__( self, key, value )

   def __setitem__( self, key, value ):
      if key in StylerFont.FIELD_NAMES:
         if key == 'bold':
            key = 'weight'
            value = 'bold' if value else 'normal'
         elif key == 'italic':
            key = 'slant'
            value = 'italic' if value else 'roman'

         self._font[ key ] = value

      else:
         if (value in Style.OFF_VALUES[key]) or (value == Style.DEFAULT_STYLE[key]):
            if key in self:
               self.__delitem__( key )
         else:
            if key == 'font':
               if isinstance( value, StylerFont ):
                  self._font = value
               else:
                  self._font = StylerFont.getFont( value )
            else:
               dict.__setitem__( self, key, value )

   def __getitem__( self, key ):
      if key in StylerFont.FIELD_NAMES:
         return self._font[ key ]
      elif key in self:
         return dict.__getitem__( self, key )
      elif key == 'font':
         return self._font

   def tagOptions( self ):
      options  = { }
      options.update( self )
      try:
         options.update( self._font.tagOptions( ) )
         lineHeight = self._font.tkFont().metrics('linespace')
      except:
         lineHeight = Style.DEFAULT_STYLE._font.tkFont().metrics('linespace')

      # Adjust fields with non-tk options
      for spacingKind in [ 'spacing1', 'spacing2', 'spacing3' ]:
         try:
            selectedSpacing = options[ spacingKind ]
            if selectedSpacing == 'None':
               options[ spacingKind ] = '0'
            elif selectedSpacing == 'Half Line':
               options[ spacingKind ] = '%dp' % int(float(lineHeight * 0.5 + 0.5))
            elif selectedSpacing == 'One Line':
               options[ spacingKind ] = '%dp' % int(lineHeight)
            elif selectedSpacing == 'Two Lines':
               options[ spacingKind ] = '%dp' % int(lineHeight * 2)
            else:
               options[ spacingKind ] = selectedSpacing
         except:
            pass

      return options

   @staticmethod
   def setup( aTextWidget ):
      StylerFont.setup( aTextWidget )
      Style.DEFAULT_STYLE = Style( font        = StylerFont.DEFAULT_FONT,
                                   foreground  = aTextWidget[ 'foreground' ],
                                   background  = aTextWidget[ 'background' ],
                                   fgstipple   = '',
                                   bgstipple   = '',
                                   borderwidth = 0,
                                   relief      = Tk.FLAT,
                                   justify     = Tk.LEFT,
                                   wrap        = Tk.CHAR,
                                   lmargin1    = 0,
                                   lmargin2    = 0,
                                   rmargin     = 0,
                                   spacing1    = 0,
                                   spacing2    = 0,
                                   spacing3    = 0,
                                   tabs        = ''
                                 )

      Style.OFF_VALUES = {
                          # Font Attributes
                          'family':     [ StylerFont.DEFAULT_FONT['family'] ],
                          'size':       [ StylerFont.DEFAULT_FONT['size'  ] ],
                          'weight':     [ Font.NORMAL, None          ],
                          'slant':      [ Font.ROMAN,  None          ],
                          'offset':     [ 'normal', '0', '0p', '0i', '0c', '0m', '', None          ],

                          # Paragraph Attributes
                          'justify':    [ Tk.LEFT, '', None ],
                          'wrap':       [ Tk.CHAR, '', None ],
                          'lmargin1':   [ '0', '0p', '0i', '0c', '0m', '', None ],
                          'lmargin2':   [ '0', '0p', '0i', '0c', '0m', '', None ],
                          'rmargin':    [ '0', '0p', '0i', '0c', '0m', '', None ],
                          'spacing1':   [ '0', '0p', '0i', '0c', '0m', 'None', '', None ],
                          'spacing2':   [ '0', '0p', '0i', '0c', '0m', 'None', '', None ],
                          'spacing3':   [ '0', '0p', '0i', '0c', '0m', 'None', '', None ],
                          'tabs':       [ '', None ],

                          # Other Attributes
                          'underline':  [ Tk.FALSE, '0', 'false', 'False', False, '', None ],
                          'overstrike': [ Tk.FALSE, '0', 'false', 'False', False, '', None ],
                          'foreground': [ aTextWidget[ 'foreground' ], '', None ],
                          'background': [ aTextWidget[ 'background' ], '', None ],
                          'fgstipple':  [ '', 'none', None ],
                          'bgstipple':  [ '', 'none', None ],
                          'borderwidth':[ '0', '0p', '0i', '0c', '0m', '', None ],
                          'relief':     [ Tk.FLAT, '', None ]
                          }

   @staticmethod
   def getStyle( aSpec=None, **options ):
      if aSpec:
         if isinstance( aSpec, str ):
            if aSpec.startswith(StylerFont.FONT_TAG_PREFIX):
               return StylerFont.getFont( aSpec )
            elif aSpec.startswith(Style.ATTRIBUTE_TAG_PREFIX):
               key,value = aSpec.replace( '_',' ' ).split('-')[2:]
               theStyle = Style( )
               theStyle[ key ] = value
               return theStyle
      if options:
         return Style( **options)


class Styler( object ):
   ATTRIBUTE_TAG_FORMAT = '-attribute-%s-%s'  # name, value
   ATTRIBUTE_TAG_PREFIX = '-attribute-'

   def __init__( self, aTextWidget ):
      self.text       = aTextWidget

      Style.setup( self.text )
      self.reinitizlize( )

   def reinitizlize( self, styles=None ):
      self.text.delete( '1.0', Tk.END )

      if styles:
         self._styles = styles
      else:
         self._styles = { }

   def applyStyleAttribute( self, index1, index2, attributeName, attributeValue ):
      '''Applies an attribute name:value pair to a given region indicated by
      index1, index2.  Index1 is part of the region, index2 is not.  Valid
      values for name and value are the same as those accepted by Style.__setitem__().
      '''
      try:
         index1 = self.text.index( index1 )
         index2 = self.text.index( index2 )
      except:
         return

      # Manipulate the styles and tags in the region
      if attributeName in ( 'family', 'size', 'weight', 'slant', 'offset', 'bold', 'italic' ):
         for beg, end, tagNameList in self.mapRegion( index1, index2 ):
            # Get the old font info (oldFontOpts) and delete the styling tag
            for oldTagName in tagNameList:
               if oldTagName.startswith( StylerFont.FONT_TAG_PREFIX ):
                  currentFont = StylerFont.getFont( oldTagName )
                  self.text.tag_remove( oldTagName, beg, end )
                  break

            else:
               currentFont = StylerFont.getFont( )

            # Calculating & Install new values
            newFont = currentFont.deriveFont( **{ attributeName:attributeValue } )
            newTagName = newFont.fontName( )

            self.text.tag_add( newTagName, beg, end )
            self.text.tag_config( newTagName, **newFont.tagOptions() )

      else:
         for beg, end, tagNameList in self.mapRegion( index1, index2 ):
            # If the attribute already exists, remove it.
            for oldTagName in tagNameList:
               if oldTagName.startswith( Styler.ATTRIBUTE_TAG_PREFIX + attributeName + '-' ):
                  self.text.tag_remove( oldTagName, beg, end )
                  break

            # If we're just deactivating, then we're done
            if attributeValue in Style.OFF_VALUES[ attributeName ]:
               continue

            # Calculate the new values
            newTagName = Styler.ATTRIBUTE_TAG_FORMAT % ( attributeName, str(attributeValue) )

            # Install the new values
            self.text.tag_add( newTagName, beg, end )
            self.text.tag_config( newTagName, **{ attributeName : attributeValue } )

   def tagNames( self, index1, index2=None ):
      tagNames = list(self.text.tag_names( index ))
      if 'sel' in styles:
         tagNames.remove( 'sel' )

      if not index2:
         return tagNames

      for action, tagName, index in self.text.dump( '1.0', Tk.END, tag=True ):
         if action == 'tagon':
            tagNames.append( tagName )

      # Rearrange the names into tag stack order
      result = [ ]
      for name in self.text.tag_names( ):
         if name in tagNames:
            result.append( name )

      return result

   def attributesAtIndex( self, index ):
      index = self.text.index( index )

      styles = self.tagNames( index )

      tagOpts  = { }
      fontOpts = { }

      for styleName in styles:
         if styleName.startswith( StylerFont.FONT_TAG_PREFIX ):
            font = StylerFont.getFont( styleName )
            tagOpts.update( **font.tagOptions() )
            fontOpts = font.fontOptions( )
         else:
            attribStyleName  = styleName.replace( '_', ' ' )
            attribName, attribValue = attribStyleName.split( '-' )[ 2: ]

            tagOpts[ attribName ] = attribValue

      return tagOpts, fontOpts

   def mapRegion( self, index1, index2 ):
      '''This method returns a map of the styles for a given region.  The result
      is a list of 'subregion' style descriptions of the form:
         ( beginIndex, endIndex, [ activeStyleNames ] )
      The list is guaranteed complete.  beginIndex of the first subregion
      description will always equal index1, and endIndex of the last subregion
      will always equal index2.  Further, for any two adjacent subregion
      descriptions endIndex of the first will always equal beginIndex of the
      second.  Thus no gaps occur in the map.
      '''
      # Build a complete dump of the region
      index1 = self.text.index( index1 )
      index2 = self.text.index( index2 )
      theDump = self.text.dump( index1, index2, tag=True )

      if len(theDump) == 0:
         return theDump

      # Consolidate the Dump
      finalReport  = [ ]

      activeTags   = list( self.text.tag_names( index1 ) )
      if 'sel' in activeTags:
         activeTags.remove( 'sel' )

      currentIndex = index1
      for action, tag, index in theDump:
         if tag == 'sel':
            continue

         if index != currentIndex:
            finalReport.append( ( currentIndex, index, copy.copy(activeTags) ) )
            currentIndex = index

         if action == 'tagon':
            if tag not in activeTags:
               activeTags.append( tag )
         elif action == 'tagoff':
            activeTags.remove( tag )

      if len(finalReport) == 0:
         finalReport = [ ( index1, index2, activeTags ) ]

      else:
         if finalReport[-1][1] != index2:
            finalReport.append( ( finalReport[-1][1], index2, copy.copy(activeTags) ) )

      return finalReport


class Edit( Tk.Frame ):
   NAME_COUNTER = 1

   def __init__( self, parent, **options ):
      Tk.Frame.__init__( self, parent )
      self.text               = None
      self.styler             = None

      self._images            = { }
      self._windows           = { }

      self._fgColorBtn        = None
      self._bgColorBtn        = None
      self._styleCombo        = None

      self._currentFontName   = Tk.StringVar( )
      self._currentFontSize   = Tk.StringVar( )
      self._currentFontOffset = Tk.StringVar( )
      self._currentFGStipple  = Tk.StringVar( )
      self._currentBGStipple  = Tk.StringVar( )
      self._currentBorder     = Tk.StringVar( )
      self._currentRelief     = Tk.StringVar( )
      self._currentJustify    = Tk.StringVar( )
      self._currentWrap       = Tk.StringVar( )
      self._currentLMargin1   = Tk.StringVar( )
      self._currentLMargin2   = Tk.StringVar( )
      self._currentRMargin    = Tk.StringVar( )
      self._currentSpacing1   = Tk.StringVar( )
      self._currentSpacing2   = Tk.StringVar( )
      self._currentSpacing3   = Tk.StringVar( )
      self._currentTabs       = Tk.StringVar( )
      self._currentStyle      = Tk.StringVar( )

      self.buildGUI( **options )

   def reinitialize( self, styles=None ):
      self