[reportlab-users] Page 1 of 3

[Robin Becker]

Robin Becker wrote:

> Juha Tuomala wrote:

>>

>> On Friday 26 January 2007 19:55, Robin Becker wrote:

>>> The onPageEnd stuff allows you to use canvas level primitives to decorate the 

>>> page. Assume you have a form called pageTotal then your page decorator does 

>>> something like

>>>

>>> canvas.doForm('pageTotal')

>>>

>>> at the appropriate place on the page. Note that the form need not be defined 

>>> when you reference it.

>>>

>>> At the end of the document build you need to set up the form using more canvas 

>>> level operations.

>>>

>>> canvas.beginForm('pageTotal')

>>> canvas.saveState()

>>>

>>> ......

>>> canvas.drawString(x,y,str(nPages))

>>> canvas.restoreState()

>>> canvas.endForm()

>>

>> I've not been playing with forms yet, so is this 

>> also possible with platypus+flowables?

>>

>> I've laid out my pages with build parameters onFirstPage

>> and onLaterPages.

>>  

>>

>> Tuju

>>

> 

> Yes you can reference the form in those functions. The hard part is knowing 

> which is the 'last' page so you can define the form. A trick will allow you to 

> do that though. Add an afterPage method to your document class that knows when 

> the story is done.

> 

> 

> Suppose your class is currently called DocA then either add an afterPage to it 

> directly or derive another class from it and add the after page to that class.

> 

> class DocB(DocA):

>      def afterPage(self):

>          if hasattr(self,'_theEndAtLast'):

>              #the last flowable has been drawn


 >              self.canv.beginForm('pageTotal')
whoops should have been
                canvas = self.canv
                canvas.beginForm('pageTotal')


>              canvas.beginForm('pageTotal')

>              canvas.saveState()

>              canvas.drawString(x,y,str(self.page))

>              canvas.restoreState()

>              canvas.endForm()

>          DocA.afterPage(self) #call the super method

> 

> 

> The trick is to add a special flowable to your story that sets the attribute 

> '_theEndAtLast' onto the document eg

> 

> class ThisIsTheEnd(ActionFlowable):

>      def apply(self,doc):

>          doc._theEndAtLast = 1

> 

> right at the end of your story creation

> 

> story.append(ThisIsTheEnd())

> 

> 

> then when that flowable is processed the story is done and the doctemplate 

> framework will eventually call afterPage so the form gets defined.



-- 
Robin Becker