[reportlab-users] RE: Table sizing algorithms - comments welcome

[Robin Becker]

In article <3EA54C26.1070400@spirito.de>, Dirk Holtwick
<holtwick@spirito.de> writes
>what about my proposal from 13th of febuary? may also be made backwards 
>compatible:
>
>Hi,
>
>here is a drop in suggestion for a more flexible table layout. for the 
>colWidths just pass a list of _width() objects and for totalWidth one 
>_width() object. Width can be
>
>    - an absolute value         (_width("1.2cm"))
>    - a percentage             (_width("33%"))
>    - a space consuming "spanner"     (_width(None))
>
>Attention, I added "align" to the init values! Was quite unhandy formerly.
>
>Enjoy,
>Dirk
>
We're considering extending along these lines.

If we're going to do this we would probably just use strings to indicate
special values ie leave the burden for the class not the client. Also we
ought to be able to indicate that % means percentage of the available
width or of the width remaining after fixed size columns. The HTML model
uses the container width as 100%. The spanner should probably be '*'.

>-----
>
>class MyTable(Table):
>
>    def __init__(self, data, align, colWidths=None,
>    totalWidth=None, rowHeights=None, style=None,
>        repeatRows=0, repeatCols=0, splitByRow=1,
>    emptyTableAction=None):
>
>        self._data = data
>        self._align = align
>        self._colwidths = colWidths
>        self._rowheights = rowHeights
>        self._style = style
>        self._repeatrows = repeatRows
>        self._repeatcols = repeatCols
>        self._splitbyrow = splitByRow
>        self._emptytableaction = emptyTableAction
>        self._notset = 1
>        self._totalwidth = totalWidth
>
>    def wrap(self, aw, ah):
>        if self._notset:
>            self._notset = 0
>
>            cw = self._colwidths
>            tw = self._totalwidth.calc(aw)
>
>            ws = []
>            sc = 0
>            sp = 0
>
>            # calculate known
>            for c in cw:
>                if c.span():
>                    ws.append(None)
>                    sc = sc + 1
>                else:
>                    v = c.calc(tw)
>                    sp = sp + v
>                    ws.append(v)
>
>            # donate space to the rest
>            cw = []
>            if sc:
>                rest = (tw - sp) / sc
>                for c in ws:
>                    if c==None:
>                        cw.append(rest)
>                    else:
>                        cw.append(c)
>            else:
>                cw = ws
>
>            Table.__init__(self,
>                self._data,
>                cw,
>                self._rowheights,
>                self._style,
>                self._repeatrows,
>                self._repeatcols,
>                self._splitbyrow,
>                self._emptytableaction)
>            self.hAlign = self._align
>
>        return Table.wrap(self, aw, ah)
>
>def get_length(s):
>    try:
>        s = str(s)
>        # for us germans, we like comma
>        s = string.replace(s,",",".")
>        if s[-2:]=='cm': return float(s[:-2])*cm
>        if s[-2:]=='in': return float(s[:-2])*inch
>        if s[-2:]=='pt': return float(s[:-2])
>        if s[-1:]=='i': return float(s[:-1])*inch
>        return float(s)
>    except:
>        raise ValueError, "Can't convert '%s' to length" % s
>
>class _width:
>
>    def __init__(self, value=None):
>        self.value = None
>        self.fix  = None
>        if value!=None:
>            self.set(value)
>
>    def set(self, value):
>        if string.find(value,"%")>=0:
>            self.value = float(
>        string.strip(string.replace(value, "%", "")))
>            self.fix = 0
>        else:
>            self.value = get_length(value)
>            self.fix = 1
>
>    def calc(self, avail):
>        if self.value==None:
>            return avail
>        if self.fix:
>            return self.value
>        else:
>            return ((avail/100.0)*self.value)
>
>    def span(self):
>        return not self.value
>
>_______________________________________________
>reportlab-users mailing list
>reportlab-users@reportlab.com
>http://two.pairlist.net/mailman/listinfo/reportlab-users

-- 
Robin Becker