Braille

20 ''' 21 Defines the basic style attributes for all L{AEOutput.Braille} devices. 22 23 DisplayColumns (integer) Number of cells in each display row. 24 25 DisplayRows (integer) Number of row in display. 26 27 TotalCells (integer) Total cells in display. 28 29 CaretStyle (enum): Current caret style 30 31 EllipsisRight (bool): Does user want right ellipsis shown? 32 33 EllipsisLeft (bool): Does user want left ellipsis shown? 34 35 EllipsisStyle (enum): Current ellipsis style 36 37 CellMask (string): Missing cell string. 0=bad cell; 1=good cell. 38 39 @cvar missingcellcnt: Count of missing cells in CellMask. Initialized as a 40 class variable for convienced, but used as an instance variable. 41 @type missingcellcnt: integer 42 ''' 43 missingcellcnt = 0 44

45 - def _initDefault(self):

46 ''' 47 Called automatically by the L{Style} base class when this style is a 48 default. Initializes all default braille options. If you want these 49 settings created, be sure to call this base class implementation if you 50 override in a subclass. 51 ''' 52 # braille display properties 53 self.newNumeric('DisplayColumns', 40, _('Columns in display'), 0, 80, 0) 54 self.newNumeric('DisplayRows', 1, _('Rows in display'), 0, 10, 0) 55 self.newNumeric('TotalCells', 40, _('Total cells in display'), 0, 800, 0) 56 self.newEnum('CaretStyle', CARET_TWO_BOTTOM, _('Caret Display Style'), 57 {_('No Caret') : CARET_NONE, 58 _('Two Bottom Pins') : CARET_TWO_BOTTOM, 59 _('Bottom Right Pins') : CARET_BOTTOM_RIGHT, 60 _('All Pins') : CARET_ALL}, 61 _('Defines the caret representation.')) 62 63 self.newBool('EllipsisRight', False, _('Ellipsis right?'), 64 _('When set, ellipsis will appear when additional text is to ' 65 'the right of the viewport.')) 66 self.newBool('EllipsisLeft', False, _('Ellipsis left?'), 67 _('When set, ellipsis will appear when additional text is to ' 68 'the left of the viewport.')) 69 self.newEnum('EllipsisStyle', ELLIPSIS_ELLIPSIS, 70 _('Ellipsis Display Style'), 71 {_('Pin 3 in 3 cells') : ELLIPSIS_ELLIPSIS, 72 _('Continuation symbol') : ELLIPSIS_CONTINUATION}, 73 _('Defines the ellipsis representation.')) 74 75 cm = self.newString('CellMask', '', _('Broken Cell String'), 76 _('String of zeros and ones indicating the functionality of ' 77 'each cell')) 78 # add observer to count missing cells on cell mask 79 cm.addObserver(self._setMissingCells)

80

81 - def _setMissingCells(self, style, setting):

82 ''' 83 Updates the missing cell count instance variable whenever the CellMask 84 setting changes value. 85 86 @param style: This style object 87 @type style: L{BrailleStyle} 88 @param setting: Setting that change value, namely CellMask 89 @type setting: L{AEState.Setting} 90 ''' 91 self.missingcellcnt = self.CellMask.count('0')

92

93 - def _newBrailleGroup(self, root):

94 ''' 95 Builds groups of standard Braille settings that should be available for all 96 Braille devices. The groups are added directly to the root group provided. 97 98 @param root: Parent group for the word settings group 99 @type root: L{AEState.Setting.Group} 100 @return: The root group again 101 @rtype: L{AEState.Setting.Group} 102 ''' 103 c = root.newGroup(_('Caret')) 104 c.append('CaretStyle') 105 d = root.newGroup(_('Ellipsis')) 106 d.append('EllipsisRight') 107 d.append('EllipsisLeft') 108 d.append('EllipsisStyle') 109 e = root.newGroup(_('Broken Cells')) 110 e.append('CellMask') 111 return root

114 ''' 115 Defines the base class for all Braille output devices. Provides default 116 implementation of L{parseString} specific to Braille devices. 117 '''

118 - def getCapabilities(self):

119 ''' 120 @return: 'braille' as the only capability of this device. 121 @rtype: list of string 122 ''' 123 return ['braille']

124

125 - def getProxy(self):

126 ''' 127 Looks at the L{AEOutput.USE_THREAD 128 <AccessEngine.AEDevice.AEOutput.Base.AEOutput.USE_THREAD>} flag to see if 129 the device implementing this interface wants a thread proxy or not. 130 131 @return: self 132 @rtype: L{AEOutput} 133 @raise NotImplementedError: When the interface wants a thread proxy. 134 ''' 135 if self.USE_THREAD == True: 136 raise NotImplementedError 137 elif self.USE_THREAD == False: 138 return self 139 else: 140 raise NotImplementedError('USE_THREAD not specified')

141

142 - def parseString(self, text, style, por, sem):

143 ''' 144 Dummy implementation returns the text as-is. 145 146 @param text: Text to be parsed 147 @type text: string 148 @param style: Style object defining how the text should be parsed 149 @type style: L{AEOutput.Style} 150 @param por: Point of regard for the first character in the text, or None if 151 the text is not associated with a POR 152 @type por: L{AEPor} 153 @param sem: Semantic tag for the text 154 @type sem: integer 155 @return: Parsed words 156 @rtype: 3-tuple of lists of string, L{AEPor}, L{AEOutput.Style} 157 ''' 158 return [(text, por, style)]

159

160 - def send(self, name, value, style=None):

161 ''' 162 Dispatches known commands to their appropriate handlers. 163 164 @param name: Descriptor of the data value sent 165 @type name: object 166 @param value: Content value 167 @type value: object 168 @param style: Style with which this value should be output 169 @type style: L{AEOutput.Style} 170 @return: Return value specific to the given command 171 @rtype: object 172 @raise NotImplementedError: When the handler for a common command is not 173 implemented by a subclass 174 ''' 175 if name == AEConstants.CMD_STOP: 176 self.sendStop(style) 177 elif name == AEConstants.CMD_TALK: 178 self.sendTalk(style) 179 elif name in (AEConstants.CMD_STRING, AEConstants.CMD_STRING_SYNC): 180 self.sendString(value, style) 181 elif name == AEConstants.CMD_FILENAME: 182 # may not be implemented 183 self.sendFilename(value, style) 184 elif name == AEConstants.CMD_CARET: 185 self.sendCaret(value, style) 186 elif name == AEConstants.CMD_TRUNCATE: 187 self.sendTruncate(value[0], value[1], style) 188 elif name == AEConstants.CMD_GET_ELLIPSIS_SIZE: 189 return self.sendGetEllipsisSizes(style) 190 elif name == AEConstants.CMD_GET_MISSINGCELL_COUNT: 191 return self.sendGetMissingCellCount()

192 193

194 - def sendCaret(self, pos, style):

195 ''' 196 Sends the current caret position relative to the first cell (zero-offset) 197 on the device. The style object is used by the device in deciding how the 198 caret should be presented. 199 200 @param pos: Zero-offset cell position of the caret, up to the device to 201 change to one-offset if need be 202 @type pos: string 203 @param style: Style with which the caret should be indicated 204 @type style: L{AEOutput.Style} 205 @raise NotImplementedError: When not overridden in a subclass 206 ''' 207 raise NotImplementedError

208

209 - def sendTruncate(self, left, right, style):

210 ''' 211 Sends indicators of whether text was truncated on either side of the 212 current line or not. The style object is used by the device in deciding how 213 the truncation should be presented. 214 215 @param left: Was text truncated to the left? 216 @type left: boolean 217 @param right: Was text truncated to the right? 218 @type right: boolean 219 @param style: Style with which the truncation should be indicated 220 @type style: L{AEOutput.Style} 221 @raise NotImplementedError: When not overridden in a subclass 222 ''' 223 raise NotImplementedError

224

225 - def sendGetEllipsisSizes(self, style):

226 ''' 227 @param style: Style with which the ellipsis are defined 228 @type style: L{AEOutput.Style} 229 @return: tuple containing length of left and right ellipsis 230 @rtype: tuple 231 @raise NotImplementedError: When not overridden in a subclass 232 ''' 233 raise NotImplementedError

234

235 - def sendGetEllipsisSizes(self, style):

236 ''' 237 @param style: Style with which the ellipsis are defined 238 @type style: L{AEOutput.Style} 239 @return: tuple containing length of left and right ellipsis 240 @rtype: tuple 241 @raise NotImplementedError: When not overridden in a subclass 242 ''' 243 raise NotImplementedError

244

245 - def sendGetEllipsisSizes(self, style):

246 ''' 247 @param style: Style with which the ellipsis are defined 248 @type style: L{AEOutput.Style} 249 @return: tuple containing length of left and right ellipsis 250 @rtype: tuple 251 @raise NotImplementedError: When not overridden in a subclass 252 ''' 253 raise NotImplementedError

254

255 - def sendGetMissingCellCount(self):

256 ''' 257 @return: integer containing missing cell count 258 @rtype: integer 259 @raise NotImplementedError: When not overridden in a subclass 260 ''' 261 raise NotImplementedError

262

263 - def sendString(self, text, style):

264 ''' 265 Sends a string of one or more characters to the device. The style object 266 is used by the device in deciding how the given text should be presented. 267 268 @param text: Text to send to the device 269 @type text: string 270 @param style: Style with which this text should be output 271 @type style: L{AEOutput.Style} 272 @raise NotImplementedError: When not overridden in a subclass 273 ''' 274 raise NotImplementedError

275

276 - def sendFilename(self, fn, style):

277 ''' 278 Sends a string filename to the device, the contents of which should be 279 output. The style object is used by the device in decided how the given 280 text should be presented. 281 282 Typically, this method should be implemented by an audio device that 283 supports playback of waveform or sequencer files. It might also be used 284 by devices as a way of synthesizing the entire contents of a file without 285 having to pass all of the contents through the rest of the system. 286 287 @param fn: Absolute filename 288 @type fn: string 289 @param style: Style with which this text should be output 290 @type style: L{AEOutput.Style} 291 @raise NotImplementedError: When not overridden in a subclass 292 ''' 293 raise NotImplementedError

294

295 - def sendStop(self, style=None):

296 ''' 297 Purges buffered text and styles, and interrupts on-going output. 298 299 @param style: Style indicating which channel on which the stop should be 300 performed; None indicates stop on all channels 301 @type style: L{AEOutput.Style} 302 @raise NotImplementedError: When not overridden in a subclass 303 ''' 304 raise NotImplementedError

305

306 - def sendTalk(self, style=None):

307 ''' 308 Indicates all text buffered by L{sendString} should now be output. 309 For devices that do the buffering in the driver, this action may mean 310 simply sending the command. For devices that do not buffer, this action 311 means sending text and styles buffered in the SUE device definition. 312 313 @param style: Style indicating which channel on which the talk should be 314 performed; None indicates talk on all channels 315 @type style: L{AEOutput.Style} 316 @raise NotImplementedError: When not overridden in a subclass 317 ''' 318 raise NotImplementedError

Source Code for Module Braille