[Development] QPrintPreview: access to single pages

[John Layt]

On Monday 31 Oct 2011 09:37:18 Giovanni Bajo wrote:
> Hi John,
> 
> thank you very much for accepting to be the printer maintainer.
> 
> Last year, we (Develer) proposed a patch that was rejected:
> http://qt.gitorious.org/qt/qt/merge_requests/733
> 
> We then opened a bug to discuss an alternative API to implement the features
> we require: https://bugreports.qt.nokia.com//browse/QTBUG-12168
> 
> (the two links above summarize our needs quite well)
> 
> If we could agree on the API at least, we could move on and submit a new
> patch.
> 
> Thanks!

Hi Giovanni,

Thanks for bringing this to my notice.  I have to confess that QPrintPreview 
is something I haven't touched and so have little knowledge of and it is on my 
learning TODO list.  I'll need to get up to speed there before I can comment 
on the proposal properly, but it does feel somewhat awkward to me.

The big hurdle is that we don't really want to make any changes to the 
existing printing code in 5.0 other than the work done to split it into a 
separate module.  We want to leave any significant changes for the new module 
in 5.1 or 5.2.  That said, if the implementation is a single new method that 
doesn't change much of the existing code and doesn't change the existing api 
or its behaviour then I would consider it.

The bug report mentions 2 points, 1) to Aquire a separate preview for each 
page and 2) the ability to print page subsets like 1,8,12.  I can say now that 
2) is not supported by Qt currently and will not be supported in QPrintSupport 
in 5.0 as it would require considerable changes to the existing code and api.  
It is a feature that will be in the new printing module though in 5.1/5.2 (in 
fact, it was writing patches to do this that led to my becoming maintainer).  

Will fixing 1) still be useful to you without 2)?

Thanks again, and I'll try get back to you in the next week or two.

John.