| 1 | |
| 2 | <html> |
| 3 | <head> |
| 4 | <meta name="description" content="Pmw - a toolkit for building high-level compound widgets in Python"> |
| 5 | <meta name="content" content="python, megawidget, mega widget, compound widget, gui, tkinter"> |
| 6 | <title>Pmw.Counter reference manual</title> |
| 7 | </head> |
| 8 | |
| 9 | <body bgcolor="#ffffff" text="#000000" link="#0000ee" |
| 10 | vlink="551a8b" alink="ff0000"> |
| 11 | |
| 12 | <h1 ALIGN="CENTER">Pmw.Counter</h1> |
| 13 | |
| 14 | <center><IMG SRC=Counter.gif ALT="" WIDTH=400 HEIGHT=110></center> |
| 15 | <dl> |
| 16 | <dt> <h3>Name</h3></dt><dd> |
| 17 | <p>Pmw.Counter() - |
| 18 | entry field with up and down arrow buttons |
| 19 | </p> |
| 20 | |
| 21 | |
| 22 | </dd> |
| 23 | <dt> <h3>Inherits</h3></dt><dd> |
| 24 | <a href="MegaWidget.html">Pmw.MegaWidget</a><br> |
| 25 | </dd> |
| 26 | <dt> <h3>Description</h3></dt><dd> |
| 27 | <p> |
| 28 | A counter contains an entry field and two arrow buttons to |
| 29 | increment and decrement the value in the entry field. Standard |
| 30 | counting types include numbers, times and dates. A user defined |
| 31 | counting function may also be supplied for specialised counting. |
| 32 | Counting can be used in combination with the entry field's |
| 33 | validation. The components may be laid out horizontally or |
| 34 | vertically.</p> |
| 35 | |
| 36 | <p> Each time an arrow button is pressed the value displayed in the |
| 37 | entry field is incremented or decremented by the value of the |
| 38 | <strong>increment</strong> option. If the new value is invalid (according to the |
| 39 | entry field's <strong>validate</strong> option, perhaps due to exceeding minimum |
| 40 | or maximum limits), the old value is restored.</p> |
| 41 | |
| 42 | <p> When an arrow button is pressed and the value displayed is not an |
| 43 | exact multiple of the <strong>increment</strong>, it is "truncated" up or down to |
| 44 | the nearest increment.</p> |
| 45 | |
| 46 | <p></p> |
| 47 | |
| 48 | |
| 49 | </dd> |
| 50 | <dt> <h3>Options</h3></dt><dd> |
| 51 | Options for this megawidget and its base |
| 52 | classes are described below.<p></p> |
| 53 | <a name=option.autorepeat></a> |
| 54 | <dl><dt> <strong>autorepeat |
| 55 | </strong></dt><dd> |
| 56 | If true, the counter will continue to count up or down while an |
| 57 | arrow button is held pressed down. The default is <strong>1</strong>.</p> |
| 58 | |
| 59 | |
| 60 | </dd></dl> |
| 61 | <a name=option.buttonaspect></a> |
| 62 | <dl><dt> <strong>buttonaspect |
| 63 | </strong></dt><dd> |
| 64 | Initialisation option. Specifies the width of the arrow buttons as a proportion of their |
| 65 | height. Values less than <strong>1.0</strong> will produce thin arrow buttons. |
| 66 | Values greater than <strong>1.0</strong> will produce fat arrow buttons. The default is <strong>1.0</strong>.</p> |
| 67 | |
| 68 | |
| 69 | </dd></dl> |
| 70 | <a name=option.datatype></a> |
| 71 | <dl><dt> <strong>datatype |
| 72 | </strong></dt><dd> |
| 73 | Specifies how the counter should count up and down.</p> |
| 74 | <p> The most general way to specify the <strong>datatype</strong> option is as a |
| 75 | dictionary. The kind of counting is specified by the <strong>'counter'</strong> |
| 76 | dictionary field, which may be either a function or the name of |
| 77 | one of the standard counters described below. If the dictionary |
| 78 | does not have a <strong>'counter'</strong> field, the field defaults to |
| 79 | <strong>'numeric'</strong>.</p> |
| 80 | |
| 81 | <p> Any other fields in the dictionary are passed on to the <em>counter</em> |
| 82 | function as keyword arguments.</p> |
| 83 | |
| 84 | <p> If <strong>datatype</strong> is not a dictionary, then it is equivalent to |
| 85 | specifying it as a dictionary with a single <strong>'counter'</strong> field. |
| 86 | For example, <code>datatype = 'real'</code> is equivalent to |
| 87 | <code>datatype = {'counter' : 'real'}</code>.</p> |
| 88 | |
| 89 | <p> The standard counters are:</p> |
| 90 | |
| 91 | <dl><dt><strong>'numeric'</strong></dt><dd>An integer number, as accepted by <code>string.atol()</code>.<p></p> |
| 92 | |
| 93 | </dd> |
| 94 | <dt><strong>'integer'</strong></dt><dd>Same as <strong>'numeric'</strong>.<p></p> |
| 95 | |
| 96 | </dd> |
| 97 | <dt><strong>'real'</strong></dt><dd>A real number, as accepted by <code>string.atof()</code>. This |
| 98 | counter accepts a <strong>'separator'</strong> argument, which specifies |
| 99 | the character used to represent the decimal point. The |
| 100 | default <strong>'separator'</strong> is <strong>'.'</strong>.<p></p> |
| 101 | |
| 102 | </dd> |
| 103 | <dt><strong>'time'</strong></dt><dd>A time specification, as accepted by |
| 104 | <code>Pmw.timestringtoseconds()</code>. This counter accepts a |
| 105 | <strong>'separator'</strong> argument, which specifies the character used to |
| 106 | separate the time fields. The default separator is <strong>':'</strong>. |
| 107 | This counter also accepts a <strong>'time24'</strong> argument. If this is |
| 108 | true, the time value is converted to a value between |
| 109 | <strong>'00:00:00'</strong> and <strong>'23:59:59'</strong>. The default is false.<p></p> |
| 110 | |
| 111 | </dd> |
| 112 | <dt><strong>'date'</strong></dt><dd>A date specification, as accepted by |
| 113 | <code>Pmw.datestringtojdn()</code>. This counter accepts a <strong>'separator'</strong> |
| 114 | argument, which specifies the character used to separate the |
| 115 | three date fields. The default is <strong>'/'</strong>. This counter also |
| 116 | accepts a <strong>'format'</strong> argument, which is passed to |
| 117 | <code>Pmw.datestringtojdn()</code> to specify the desired ordering of the |
| 118 | fields. The default is <strong>'ymd'</strong>. |
| 119 | This counter also accepts a <strong>'yyyy'</strong> argument. If this is |
| 120 | false, the year field will be displayed as the year within the |
| 121 | century, otherwise it will be fully displayed. In both cases |
| 122 | it will be displayed with at least 2 digits, using leading |
| 123 | zeroes. The default is false.<p></p> |
| 124 | |
| 125 | </dd></dl> |
| 126 | <p> If the <strong>'counter'</strong> dictionary field is a function, then it will be |
| 127 | called whenever the counter is to be incremented or decremented. |
| 128 | The function is called with at least three arguments, the first |
| 129 | three being (<em>text</em>, <em>factor</em>, <em>increment</em>), where <em>text</em> is the |
| 130 | current contents of the entry field, <em>factor</em> is <strong>1</strong> when |
| 131 | incrementing or <strong>-1</strong> when decrementing, and <em>increment</em> is the |
| 132 | value of the <strong>increment</strong> megawidget option.</p> |
| 133 | |
| 134 | <p> The other arguments are keyword arguments made up of the fields of |
| 135 | the <strong>datatype</strong> dictionary (excluding the <strong>'counter'</strong> field).</p> |
| 136 | |
| 137 | <p> The <em>counter</em> function should return a string representing the |
| 138 | incremented or decremented value. It should raise a |
| 139 | <strong>ValueError</strong> exception if the <em>text</em> is invalid. In this case the |
| 140 | bell is rung and the entry text is not changed.</p> |
| 141 | |
| 142 | <p> The default for <strong>datatype</strong> is <strong>numeric</strong>.</p> |
| 143 | |
| 144 | |
| 145 | |
| 146 | </dd></dl> |
| 147 | <a name=option.increment></a> |
| 148 | <dl><dt> <strong>increment |
| 149 | </strong></dt><dd> |
| 150 | Specifies how many units should be added or subtracted when the |
| 151 | counter is incremented or decremented. If the currently displayed |
| 152 | value is not a multiple of <strong>increment</strong>, the value is changed to |
| 153 | the next multiple greater or less than the current value.</p> |
| 154 | <p> For the number datatypes, the value of <strong>increment</strong> is a number. |
| 155 | For the <strong>'time'</strong> datatype, the value is in seconds. For the |
| 156 | <strong>'date'</strong> datatype, the value is in days. The default is <strong>1</strong>.</p> |
| 157 | |
| 158 | |
| 159 | |
| 160 | </dd></dl> |
| 161 | <a name=option.initwait></a> |
| 162 | <dl><dt> <strong>initwait |
| 163 | </strong></dt><dd> |
| 164 | Specifies the initial delay (in milliseconds) before a depressed |
| 165 | arrow button automatically starts to repeat counting. The default is <strong>300</strong>.</p> |
| 166 | |
| 167 | |
| 168 | </dd></dl> |
| 169 | <a name=option.labelmargin></a> |
| 170 | <dl><dt> <strong>labelmargin |
| 171 | </strong></dt><dd> |
| 172 | Initialisation option. If the <strong>labelpos</strong> option is not <strong>None</strong>, this specifies the |
| 173 | distance between the <strong>label</strong> component and the rest of the |
| 174 | megawidget. The default is <strong>0</strong>.</p> |
| 175 | |
| 176 | |
| 177 | </dd></dl> |
| 178 | <a name=option.labelpos></a> |
| 179 | <dl><dt> <strong>labelpos |
| 180 | </strong></dt><dd> |
| 181 | Initialisation option. Specifies where to place the <strong>label</strong> component. If not |
| 182 | <strong>None</strong>, it should be a concatenation of one or two of the |
| 183 | letters <strong>'n'</strong>, <strong>'s'</strong>, <strong>'e'</strong> and <strong>'w'</strong>. The first letter |
| 184 | specifies on which side of the megawidget to place the label. |
| 185 | If a second letter is specified, it indicates where on that |
| 186 | side to place the label. For example, if <strong>labelpos</strong> is <strong>'w'</strong>, |
| 187 | the label is placed in the center of the left hand side; if |
| 188 | it is <strong>'wn'</strong>, the label is placed at the top of the left |
| 189 | hand side; if it is <strong>'ws'</strong>, the label is placed at the |
| 190 | bottom of the left hand side.</p> |
| 191 | <p> If <strong>None</strong>, a label component is not created. The default is <strong>None</strong>.</p> |
| 192 | |
| 193 | |
| 194 | |
| 195 | </dd></dl> |
| 196 | <a name=option.orient></a> |
| 197 | <dl><dt> <strong>orient |
| 198 | </strong></dt><dd> |
| 199 | Initialisation option. Specifies whether the arrow buttons should appear to the left and |
| 200 | right of the entry field (<strong>'horizontal'</strong>) or above and below |
| 201 | (<strong>'vertical'</strong>). The default is <strong>'horizontal'</strong>.</p> |
| 202 | |
| 203 | |
| 204 | </dd></dl> |
| 205 | <a name=option.padx></a> |
| 206 | <dl><dt> <strong>padx |
| 207 | </strong></dt><dd> |
| 208 | Initialisation option. Specifies a padding distance to leave around the arrow buttons in |
| 209 | the x direction. The default is <strong>0</strong>.</p> |
| 210 | |
| 211 | |
| 212 | </dd></dl> |
| 213 | <a name=option.pady></a> |
| 214 | <dl><dt> <strong>pady |
| 215 | </strong></dt><dd> |
| 216 | Initialisation option. Specifies a padding distance to leave around the arrow buttons in |
| 217 | the y direction. The default is <strong>0</strong>.</p> |
| 218 | |
| 219 | |
| 220 | </dd></dl> |
| 221 | <a name=option.repeatrate></a> |
| 222 | <dl><dt> <strong>repeatrate |
| 223 | </strong></dt><dd> |
| 224 | Specifies the delay (in milliseconds) between automatic counts |
| 225 | while an arrow button is held pressed down. The default is <strong>50</strong>.</p> |
| 226 | |
| 227 | |
| 228 | </dd></dl> |
| 229 | <a name=option.sticky></a> |
| 230 | <dl><dt> <strong>sticky |
| 231 | </strong></dt><dd> |
| 232 | Initialisation option. The default is <strong>'ew'</strong>.</p> |
| 233 | |
| 234 | |
| 235 | </dd></dl> |
| 236 | </dd> |
| 237 | <dt> <h3>Components</h3></dt><dd> |
| 238 | Components created by this megawidget and its base |
| 239 | classes are described below.<p></p> |
| 240 | <a name=component.downarrow></a> |
| 241 | <dl><dt> <strong>downarrow |
| 242 | </strong></dt><dd> |
| 243 | The arrow button used for decrementing the counter. Depending on |
| 244 | the value of <strong>orient</strong>, it will appear on the left or below the |
| 245 | entry field. By default, this component is a Tkinter.Canvas. Its component group is <strong>Arrow</strong>.</p> |
| 246 | |
| 247 | |
| 248 | </dd></dl> |
| 249 | <a name=component.entryfield></a> |
| 250 | <dl><dt> <strong>entryfield |
| 251 | </strong></dt><dd> |
| 252 | The entry field widget where the text is entered, displayed and |
| 253 | validated. By default, this component is a <a href="EntryField.html">Pmw.EntryField</a>.</p> |
| 254 | |
| 255 | |
| 256 | </dd></dl> |
| 257 | <a name=component.frame></a> |
| 258 | <dl><dt> <strong>frame |
| 259 | </strong></dt><dd> |
| 260 | If the <strong>label</strong> component has been created (that is, the <strong>labelpos</strong> |
| 261 | option is not <strong>None</strong>), the <strong>frame</strong> component is created to act as |
| 262 | the container of the entry field and arrow buttons. If there is |
| 263 | no <strong>label</strong> component, then no <strong>frame</strong> component is created and the |
| 264 | <strong>hull</strong> component acts as the container. In either case the border |
| 265 | around the container of the entry field and arrow buttons will be |
| 266 | raised (but not around the label). By default, this component is a Tkinter.Frame.</p> |
| 267 | |
| 268 | |
| 269 | </dd></dl> |
| 270 | <a name=component.hull></a> |
| 271 | <dl><dt> <strong>hull |
| 272 | </strong></dt><dd> |
| 273 | This acts as the body for the entire megawidget. Other components |
| 274 | are created as children of the hull to further specialise this |
| 275 | class. By default, this component is a Tkinter.Frame.</p> |
| 276 | |
| 277 | |
| 278 | </dd></dl> |
| 279 | <a name=component.label></a> |
| 280 | <dl><dt> <strong>label |
| 281 | </strong></dt><dd> |
| 282 | If the <strong>labelpos</strong> option is not <strong>None</strong>, this component is |
| 283 | created as a text label for the megawidget. See the |
| 284 | <strong>labelpos</strong> option for details. Note that to set, for example, |
| 285 | the <strong>text</strong> option of the label, you need to use the <strong>label_text</strong> |
| 286 | component option. By default, this component is a Tkinter.Label.</p> |
| 287 | |
| 288 | |
| 289 | </dd></dl> |
| 290 | <a name=component.uparrow></a> |
| 291 | <dl><dt> <strong>uparrow |
| 292 | </strong></dt><dd> |
| 293 | The arrow button used for incrementing the counter. Depending on |
| 294 | the value of <strong>orient</strong>, it will appear on the right or above the |
| 295 | entry field. By default, this component is a Tkinter.Canvas. Its component group is <strong>Arrow</strong>.</p> |
| 296 | |
| 297 | |
| 298 | </dd></dl> |
| 299 | </dd> |
| 300 | <dt> <h3>Component aliases</h3></dt><dd> |
| 301 | Sub-components of components of this megawidget |
| 302 | may be accessed via the following aliases.<p></p> |
| 303 | <dl><dt> <strong>entry |
| 304 | </strong></dt><dd> |
| 305 | Alias for <strong>entryfield_entry</strong>. |
| 306 | </dd></dl> |
| 307 | </dd> |
| 308 | <a name=methods></a> |
| 309 | <dt> <h3>Methods</h3></dt><dd> |
| 310 | Only methods specific to this megawidget are described below. |
| 311 | For a description of its inherited methods, see the |
| 312 | manual for its base class |
| 313 | <strong><a href="MegaWidget.html#methods">Pmw.MegaWidget</a></strong>. |
| 314 | In addition, methods from the |
| 315 | <strong><a href="EntryField.html#methods">Pmw.EntryField</a></strong> class |
| 316 | are forwarded by this megawidget to the |
| 317 | <strong>entryfield</strong> component. |
| 318 | <p></p> |
| 319 | <a name=method.decrement></a> |
| 320 | <dl><dt> <strong>decrement</strong>()</dt><dd> |
| 321 | Decrement the counter once, as if the down arrow had been pressed.</p> |
| 322 | |
| 323 | |
| 324 | </dd></dl> |
| 325 | <a name=method.increment></a> |
| 326 | <dl><dt> <strong>increment</strong>()</dt><dd> |
| 327 | Increment the counter once, as if the up arrow had been pressed.</p> |
| 328 | |
| 329 | |
| 330 | </dd></dl> |
| 331 | </dd> |
| 332 | <dt> <h3>Example</h3></dt><dd> |
| 333 | The image at the top of this manual is a snapshot |
| 334 | of the window (or part of the window) produced |
| 335 | by the following code.<p></p> |
| 336 | <pre> |
| 337 | class Demo: |
| 338 | def __init__(self, parent): |
| 339 | # Need to use long ints here because on the Macintosh the maximum size |
| 340 | # of an integer is smaller than the value returned by time.time(). |
| 341 | now = (long(time.time()) / 300) * 300 |
| 342 | |
| 343 | # Create the Counters. |
| 344 | self._date = Pmw.Counter(parent, |
| 345 | labelpos = 'w', |
| 346 | label_text = 'Date (4-digit year):', |
| 347 | entryfield_value = |
| 348 | time.strftime('%d/%m/%Y', time.localtime(now)), |
| 349 | entryfield_command = self.execute, |
| 350 | entryfield_validate = {'validator' : 'date', 'format' : 'dmy'}, |
| 351 | datatype = {'counter' : 'date', 'format' : 'dmy', 'yyyy' : 1}) |
| 352 | |
| 353 | self._isodate = Pmw.Counter(parent, |
| 354 | labelpos = 'w', |
| 355 | label_text = 'ISO-Date (4-digit year):', |
| 356 | entryfield_value = |
| 357 | time.strftime('%Y-%m-%d', time.localtime(now)), |
| 358 | entryfield_command = self.execute, |
| 359 | entryfield_validate = {'validator' : 'date', 'format' : 'ymd', |
| 360 | 'separator' : '-' }, |
| 361 | datatype = {'counter' : 'date', 'format' : 'ymd', 'yyyy' : 1, |
| 362 | 'separator' : '-' }) |
| 363 | |
| 364 | self._time = Pmw.Counter(parent, |
| 365 | labelpos = 'w', |
| 366 | label_text = 'Time:', |
| 367 | entryfield_value = |
| 368 | time.strftime('%H:%M:%S', time.localtime(now)), |
| 369 | entryfield_validate = {'validator' : 'time', |
| 370 | 'min' : '00:00:00', 'max' : '23:59:59', |
| 371 | 'minstrict' : 0, 'maxstrict' : 0}, |
| 372 | datatype = {'counter' : 'time', 'time24' : 1}, |
| 373 | increment=5*60) |
| 374 | self._real = Pmw.Counter(parent, |
| 375 | labelpos = 'w', |
| 376 | label_text = 'Real (with comma)\nand extra\nlabel lines:', |
| 377 | label_justify = 'left', |
| 378 | entryfield_value = '1,5', |
| 379 | datatype = {'counter' : 'real', 'separator' : ','}, |
| 380 | entryfield_validate = {'validator' : 'real', |
| 381 | 'min' : '-2,0', 'max' : '5,0', |
| 382 | 'separator' : ','}, |
| 383 | increment = 0.1) |
| 384 | self._custom = Pmw.Counter(parent, |
| 385 | labelpos = 'w', |
| 386 | label_text = 'Custom:', |
| 387 | entryfield_value = specialword[:4], |
| 388 | datatype = _custom_counter, |
| 389 | entryfield_validate = _custom_validate) |
| 390 | self._int = Pmw.Counter(parent, |
| 391 | labelpos = 'w', |
| 392 | label_text = 'Vertical integer:', |
| 393 | orient = 'vertical', |
| 394 | entry_width = 2, |
| 395 | entryfield_value = 50, |
| 396 | entryfield_validate = {'validator' : 'integer', |
| 397 | 'min' : 0, 'max' : 99} |
| 398 | ) |
| 399 | |
| 400 | counters = (self._date, self._isodate, self._time, self._real, |
| 401 | self._custom) |
| 402 | Pmw.alignlabels(counters) |
| 403 | |
| 404 | # Pack them all. |
| 405 | for counter in counters: |
| 406 | counter.pack(fill='both', expand=1, padx=10, pady=5) |
| 407 | self._int.pack(padx=10, pady=5) |
| 408 | |
| 409 | def execute(self): |
| 410 | print 'Return pressed, value is', self._date.get() |
| 411 | |
| 412 | specialword = 'Monti Python ik den Holie Grailen (Bok)' |
| 413 | |
| 414 | def _custom_validate(text): |
| 415 | if string.find(specialword, text) == 0: |
| 416 | return 1 |
| 417 | else: |
| 418 | return -1 |
| 419 | |
| 420 | def _custom_counter(text, factor, increment): |
| 421 | # increment is ignored here. |
| 422 | if string.find(specialword, text) == 0: |
| 423 | length = len(text) |
| 424 | if factor == 1: |
| 425 | if length >= len(specialword): |
| 426 | raise ValueError, 'maximum length reached' |
| 427 | return specialword[:length + 1] |
| 428 | else: |
| 429 | if length == 0: |
| 430 | raise ValueError, 'empty string' |
| 431 | return specialword[:length - 1] |
| 432 | else: |
| 433 | raise ValueError, 'bad string ' + text |
| 434 | |
| 435 | </pre> |
| 436 | </dd> |
| 437 | </dl> |
| 438 | |
| 439 | <center><P ALIGN="CENTER"> |
| 440 | <IMG SRC = blue_line.gif ALT = "" WIDTH=320 HEIGHT=5> |
| 441 | </p></center> |
| 442 | |
| 443 | |
| 444 | <font size=-1> |
| 445 | <center><P ALIGN="CENTER"> |
| 446 | Pmw 1.2 - |
| 447 | 5 Aug 2003 |
| 448 | - <a href="index.html">Home</a> |
| 449 | <br>Manual page last reviewed: 24 May 1998 |
| 450 | </p></center> |
| 451 | </font> |
| 452 | |
| 453 | </body> |
| 454 | </html> |
| 455 | |