[reportlab-users] Crashing when table goes over a page

[Robin Becker]

In article <$2BOKIAWtiJ$EwI6@jessikat.fsnet.co.uk>, Robin Becker
<robin@reportlab.com> writes
>In article <002501c3556e$3b076610$8a01010a@gkiddxp2>, Garth Kidd <garth@deadlybl
>oodyserious.com>
>writes
>>Further to my last mail; today's report run doesn't trigger the problem, so
>>I've got a new one. :) 
>>
>>After a few inches' content, my story has a KeepTogether of a header, space,
>>long table, and then another space. The table is longer than a page. What I
>>want to happen is for the header, space, and first part of the table to
>>appear in the remaining 4/5 of the first page, continuing on the second.
>>Instead the table doesn't start until page 2 (leaving a lot of empty space),
>>fills page 2, and then continues on page 3. 
>>
>>When I specify a KeepTogether, what I want is for Platypus to ensure that
>>each item starts adjacent to the end of the previous item. That aside, I
>>want to fill pages as much as is possible. 
>>
>>Anyone have any ideas on a quick fix? I'd really much rather be
>>concentrating on advanced graphing than fixing basic document flow
>>functionality. 
>>
>>Regards,
>>Garth.
>The keep together tries to do what you want, unfortunately it doesn't know the 
>total frame
>height when attempting to split itself. If it did it could perform the split 
>more rationally.
>Without that information it can only attempt to get the most space for itself.
>
>We could make a more acceptable keepTogether by giving it an extra argument 
>specifying the frame
>height to be assumed for simple (non-page throw splitting).
>
>This isn't tested so be careful.
>
>class KeepTogether(Flowable):
>        def __init__(self,flowables,maxHeight=None):
>                if type(flowables) not in _SeqTypes:
>                        self._flowables = [flowables]
>                else:
>                        self._flowables = flowables
>                self._maxHeight = maxHeight
>
>        def __repr__(self):
>                f = self._flowables
>                L = map(repr,f)
>                import string
>                L = "\n"+string.join(L, "\n")
>                L = string.replace(L, "\n", "\n  ")
>                return "KeepTogether(%s,maxHeight=%s) # end KeepTogether" % 
>(L,self._maxHeight)
>
>        def wrap(self, aW, aH):
>                W = 0
>                H = 0
>                F = self._flowables
>                canv = self.canv
>                for f in F:
>                        w,h = f.wrapOn(canv,aW,0xfffffff)
>                        if f is not F[0]: h = h + f.getSpaceBefore()
>                        if f is not F[-1]: h = h + f.getSpaceAfter()
>                        W = max(W,w)
>                        H = H+h
>                self._CPage = (H>aH) and (H<=self._maxHeight)

this should be

                self._CPage = (H>aH) and (not self._maxHeight or
H<=self._maxHeight)
>                return W, 0xffffff      # force a split
>
>        def split(self, aW, aH):
>                S = getattr(self,'_CPage',1) and [CondPageBreak(aH+1)] or []
>                for f in self._flowables: S.append(f)
>                return S
>

-- 
Robin Becker