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<h1 ALIGN=
"CENTER">Pmw.Counter
</h1>
<center><IMG SRC=Counter.gif
ALT=
"" WIDTH=
400 HEIGHT=
110></center>
<dt> <h3>Name
</h3></dt><dd>
entry field with up and down arrow buttons
<dt> <h3>Inherits
</h3></dt><dd>
<a href=
"MegaWidget.html">Pmw.MegaWidget
</a><br>
<dt> <h3>Description
</h3></dt><dd>
A counter contains an entry field and two arrow buttons to
increment and decrement the value in the entry field. Standard
counting types include numbers, times and dates. A user defined
counting function may also be supplied for specialised counting.
Counting can be used in combination with the entry field's
validation. The components may be laid out horizontally or
<p> Each time an arrow button is pressed the value displayed in the
entry field is incremented or decremented by the value of the
<strong>increment
</strong> option. If the new value is invalid (according to the
entry field's
<strong>validate
</strong> option, perhaps due to exceeding minimum
or maximum limits), the old value is restored.
</p><p> When an arrow button is pressed and the value displayed is not an
exact multiple of the
<strong>increment
</strong>, it is
"truncated" up or down to
the nearest increment.
</p><dt> <h3>Options
</h3></dt><dd>
Options for this megawidget and its base
classes are described below.
<p></p><a name=option.autorepeat
></a>
<dl><dt> <strong>autorepeat
If true, the counter will continue to count up or down while an
arrow button is held pressed down. The default is
<strong>1</strong>.
</p><a name=option.buttonaspect
></a>
<dl><dt> <strong>buttonaspect
Initialisation option. Specifies the width of the arrow buttons as a proportion of their
height. Values less than
<strong>1.0</strong> will produce thin arrow buttons.
Values greater than
<strong>1.0</strong> will produce fat arrow buttons. The default is
<strong>1.0</strong>.
</p><a name=option.datatype
></a>
<dl><dt> <strong>datatype
Specifies how the counter should count up and down.
</p><p> The most general way to specify the
<strong>datatype
</strong> option is as a
dictionary. The kind of counting is specified by the
<strong>'counter'
</strong> dictionary field, which may be either a function or the name of
one of the standard counters described below. If the dictionary
does not have a
<strong>'counter'
</strong> field, the field defaults to
<strong>'numeric'
</strong>.
</p>
<p> Any other fields in the dictionary are passed on to the
<em>counter
</em>
function as keyword arguments.
</p><p> If
<strong>datatype
</strong> is not a dictionary, then it is equivalent to
specifying it as a dictionary with a single
<strong>'counter'
</strong> field.
For example,
<code>datatype = 'real'
</code> is equivalent to
<code>datatype = {'counter' : 'real'}
</code>.
</p>
<p> The standard counters are:
</p>
<dl><dt><strong>'numeric'
</strong></dt><dd>An integer number, as accepted by
<code>string.atol()
</code>.
<p></p>
<dt><strong>'integer'
</strong></dt><dd>Same as
<strong>'numeric'
</strong>.
<p></p>
<dt><strong>'real'
</strong></dt><dd>A real number, as accepted by
<code>string.atof()
</code>. This
counter accepts a
<strong>'separator'
</strong> argument, which specifies
the character used to represent the decimal point. The
default
<strong>'separator'
</strong> is
<strong>'.'
</strong>.
<p></p><dt><strong>'time'
</strong></dt><dd>A time specification, as accepted by
<code>Pmw.timestringtoseconds()
</code>. This counter accepts a
<strong>'separator'
</strong> argument, which specifies the character used to
separate the time fields. The default separator is
<strong>':'
</strong>.
This counter also accepts a
<strong>'time24'
</strong> argument. If this is
true, the time value is converted to a value between
<strong>'
00:
00:
00'
</strong> and
<strong>'
23:
59:
59'
</strong>. The default is false.
<p></p>
<dt><strong>'date'
</strong></dt><dd>A date specification, as accepted by
<code>Pmw.datestringtojdn()
</code>. This counter accepts a
<strong>'separator'
</strong>
argument, which specifies the character used to separate the
three date fields. The default is
<strong>'/'
</strong>. This counter also
accepts a
<strong>'format'
</strong> argument, which is passed to
<code>Pmw.datestringtojdn()
</code> to specify the desired ordering of the
fields. The default is
<strong>'ymd'
</strong>.
This counter also accepts a
<strong>'yyyy'
</strong> argument. If this is
false, the year field will be displayed as the year within the
century, otherwise it will be fully displayed. In both cases
it will be displayed with at least
2 digits, using leading
zeroes. The default is false.
<p></p><p> If the
<strong>'counter'
</strong> dictionary field is a function, then it will be
called whenever the counter is to be incremented or decremented.
The function is called with at least three arguments, the first
three being (
<em>text
</em>,
<em>factor
</em>,
<em>increment
</em>), where
<em>text
</em> is the
current contents of the entry field,
<em>factor
</em> is
<strong>1</strong> when
incrementing or
<strong>-
1</strong> when decrementing, and
<em>increment
</em> is the
value of the
<strong>increment
</strong> megawidget option.
</p><p> The other arguments are keyword arguments made up of the fields of
the
<strong>datatype
</strong> dictionary (excluding the
<strong>'counter'
</strong> field).
</p><p> The
<em>counter
</em> function should return a string representing the
incremented or decremented value. It should raise a
<strong>ValueError
</strong> exception if the
<em>text
</em> is invalid. In this case the
bell is rung and the entry text is not changed.
</p><p> The default for
<strong>datatype
</strong> is
<strong>numeric
</strong>.
</p>
<a name=option.increment
></a>
<dl><dt> <strong>increment
Specifies how many units should be added or subtracted when the
counter is incremented or decremented. If the currently displayed
value is not a multiple of
<strong>increment
</strong>, the value is changed to
the next multiple greater or less than the current value.
</p><p> For the number datatypes, the value of
<strong>increment
</strong> is a number.
For the
<strong>'time'
</strong> datatype, the value is in seconds. For the
<strong>'date'
</strong> datatype, the value is in days. The default is
<strong>1</strong>.
</p>
<a name=option.initwait
></a>
<dl><dt> <strong>initwait
Specifies the initial delay (in milliseconds) before a depressed
arrow button automatically starts to repeat counting. The default is
<strong>300</strong>.
</p><a name=option.labelmargin
></a>
<dl><dt> <strong>labelmargin
Initialisation option. If the
<strong>labelpos
</strong> option is not
<strong>None
</strong>, this specifies the
distance between the
<strong>label
</strong> component and the rest of the
megawidget. The default is
<strong>0</strong>.
</p><a name=option.labelpos
></a>
<dl><dt> <strong>labelpos
Initialisation option. Specifies where to place the
<strong>label
</strong> component. If not
<strong>None
</strong>, it should be a concatenation of one or two of the
letters
<strong>'n'
</strong>,
<strong>'s'
</strong>,
<strong>'e'
</strong> and
<strong>'w'
</strong>. The first letter
specifies on which side of the megawidget to place the label.
If a second letter is specified, it indicates where on that
side to place the label. For example, if
<strong>labelpos
</strong> is
<strong>'w'
</strong>,
the label is placed in the center of the left hand side; if
it is
<strong>'wn'
</strong>, the label is placed at the top of the left
hand side; if it is
<strong>'ws'
</strong>, the label is placed at the
bottom of the left hand side.
</p><p> If
<strong>None
</strong>, a label component is not created. The default is
<strong>None
</strong>.
</p>
<a name=option.orient
></a>
Initialisation option. Specifies whether the arrow buttons should appear to the left and
right of the entry field (
<strong>'horizontal'
</strong>) or above and below
(
<strong>'vertical'
</strong>). The default is
<strong>'horizontal'
</strong>.
</p>Initialisation option. Specifies a padding distance to leave around the arrow buttons in
the x direction. The default is
<strong>0</strong>.
</p>Initialisation option. Specifies a padding distance to leave around the arrow buttons in
the y direction. The default is
<strong>0</strong>.
</p><a name=option.repeatrate
></a>
<dl><dt> <strong>repeatrate
Specifies the delay (in milliseconds) between automatic counts
while an arrow button is held pressed down. The default is
<strong>50</strong>.
</p><a name=option.sticky
></a>
Initialisation option. The default is
<strong>'ew'
</strong>.
</p><dt> <h3>Components
</h3></dt><dd>
Components created by this megawidget and its base
classes are described below.
<p></p><a name=component.downarrow
></a>
<dl><dt> <strong>downarrow
The arrow button used for decrementing the counter. Depending on
the value of
<strong>orient
</strong>, it will appear on the left or below the
entry field. By default, this component is a Tkinter.Canvas. Its component group is
<strong>Arrow
</strong>.
</p><a name=component.entryfield
></a>
<dl><dt> <strong>entryfield
The entry field widget where the text is entered, displayed and
validated. By default, this component is a
<a href=
"EntryField.html">Pmw.EntryField
</a>.
</p><a name=component.frame
></a>
If the
<strong>label
</strong> component has been created (that is, the
<strong>labelpos
</strong> option is not
<strong>None
</strong>), the
<strong>frame
</strong> component is created to act as
the container of the entry field and arrow buttons. If there is
no
<strong>label
</strong> component, then no
<strong>frame
</strong> component is created and the
<strong>hull
</strong> component acts as the container. In either case the border
around the container of the entry field and arrow buttons will be
raised (but not around the label). By default, this component is a Tkinter.Frame.
</p><a name=component.hull
></a>
This acts as the body for the entire megawidget. Other components
are created as children of the hull to further specialise this
class. By default, this component is a Tkinter.Frame.
</p><a name=component.label
></a>
If the
<strong>labelpos
</strong> option is not
<strong>None
</strong>, this component is
created as a text label for the megawidget. See the
<strong>labelpos
</strong> option for details. Note that to set, for example,
the
<strong>text
</strong> option of the label, you need to use the
<strong>label_text
</strong> component option. By default, this component is a Tkinter.Label.
</p><a name=component.uparrow
></a>
The arrow button used for incrementing the counter. Depending on
the value of
<strong>orient
</strong>, it will appear on the right or above the
entry field. By default, this component is a Tkinter.Canvas. Its component group is
<strong>Arrow
</strong>.
</p><dt> <h3>Component aliases
</h3></dt><dd>
Sub-components of components of this megawidget
may be accessed via the following aliases.
<p></p>Alias for
<strong>entryfield_entry
</strong>.
<dt> <h3>Methods
</h3></dt><dd>
Only methods specific to this megawidget are described below.
For a description of its inherited methods, see the
manual for its base class
<strong><a href=
"MegaWidget.html#methods">Pmw.MegaWidget
</a></strong>.
In addition, methods from the
<strong><a href=
"EntryField.html#methods">Pmw.EntryField
</a></strong> class
are forwarded by this megawidget to the
<strong>entryfield
</strong> component.
<a name=method.decrement
></a>
<dl><dt> <strong>decrement
</strong>()
</dt><dd>
Decrement the counter once, as if the down arrow had been pressed.
</p><a name=method.increment
></a>
<dl><dt> <strong>increment
</strong>()
</dt><dd>
Increment the counter once, as if the up arrow had been pressed.
</p><dt> <h3>Example
</h3></dt><dd>
The image at the top of this manual is a snapshot
of the window (or part of the window) produced
by the following code.
<p></p> def __init__(self, parent):
# Need to use long ints here because on the Macintosh the maximum size
# of an integer is smaller than the value returned by time.time().
now = (long(time.time()) /
300) *
300 self._date = Pmw.Counter(parent,
label_text = 'Date (
4-digit year):',
time.strftime('%d/%m/%Y', time.localtime(now)),
entryfield_command = self.execute,
entryfield_validate = {'validator' : 'date', 'format' : 'dmy'},
datatype = {'counter' : 'date', 'format' : 'dmy', 'yyyy' :
1})
self._isodate = Pmw.Counter(parent,
label_text = 'ISO-Date (
4-digit year):',
time.strftime('%Y-%m-%d', time.localtime(now)),
entryfield_command = self.execute,
entryfield_validate = {'validator' : 'date', 'format' : 'ymd',
datatype = {'counter' : 'date', 'format' : 'ymd', 'yyyy' :
1,
self._time = Pmw.Counter(parent,
time.strftime('%H:%M:%S', time.localtime(now)),
entryfield_validate = {'validator' : 'time',
'min' : '
00:
00:
00', 'max' : '
23:
59:
59',
'minstrict' :
0, 'maxstrict' :
0},
datatype = {'counter' : 'time', 'time24' :
1},
self._real = Pmw.Counter(parent,
label_text = 'Real (with comma)\nand extra\nlabel lines:',
entryfield_value = '
1,
5',
datatype = {'counter' : 'real', 'separator' : ','},
entryfield_validate = {'validator' : 'real',
'min' : '-
2,
0', 'max' : '
5,
0',
self._custom = Pmw.Counter(parent,
entryfield_value = specialword[:
4],
datatype = _custom_counter,
entryfield_validate = _custom_validate)
self._int = Pmw.Counter(parent,
label_text = 'Vertical integer:',
entryfield_validate = {'validator' : 'integer',
counters = (self._date, self._isodate, self._time, self._real,
Pmw.alignlabels(counters)
counter.pack(fill='both', expand=
1, padx=
10, pady=
5)
self._int.pack(padx=
10, pady=
5)
print 'Return pressed, value is', self._date.get()
specialword = 'Monti Python ik den Holie Grailen (Bok)'
def _custom_validate(text):
if string.find(specialword, text) ==
0:
def _custom_counter(text, factor, increment):
# increment is ignored here.
if string.find(specialword, text) ==
0:
if length
>= len(specialword):
raise ValueError, 'maximum length reached'
return specialword[:length +
1]
raise ValueError, 'empty string'
return specialword[:length -
1]
raise ValueError, 'bad string ' + text
<center><P ALIGN=
"CENTER">
<IMG SRC = blue_line.gif ALT =
"" WIDTH=
320 HEIGHT=
5>
<center><P ALIGN=
"CENTER">
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<a href=
"index.html">Home
</a> <br>Manual page last reviewed:
24 May
1998
projects / OpenSPARC-T2-SAM / blob