BBC BASIC for Windows
Programming >> Operating System >> Print Preview
http://bb4w.conforums.com/index.cgi?board=os&action=display&num=1369163597
Print Preview
Post by Matt on May 21st, 2013, 7:13pm

Hi,

Is there a Windows Print Preview utility that can be called, or would any print preview screen need to be completely set up from scratch?

Matt
Re: Print Preview
Post by admin on May 22nd, 2013, 08:22am

on May 21st, 2013, 7:13pm, Matt wrote:
Is there a Windows Print Preview utility that can be called, or would any print preview screen need to be completely set up from scratch?

There's some support in .NET but that's not a lot of use to a BB4W programmer, so realistically you would need to create your own.

It's not too difficult, however. The way I would probably do it is to write all my 'printing' routines so that they take as a parameter the output DC. Then when printing normally I would pass @prthdc% as the parameter, and when doing the Print Preview I'd pass a memory DC that I had created for the purpose.

That way exactly the same code is being used to output to the Print Preview as to the printer itself, which is the best way to guarantee an accurate preview.

Richard.
Re: Print Preview
Post by Matt on May 23rd, 2013, 05:31am

Thanks Richard.

on May 22nd, 2013, 08:22am, Richard Russell wrote:
The way I would probably do it is to write all my 'printing' routines so that they take as a parameter the output DC. Then when printing normally I would pass @prthdc% as the parameter, and when doing the Print Preview I'd pass a memory DC that I had created for the purpose.
Richard.


To be honest, I'm not sure what most of this means as I haven't done much with device contexts specifically. Any printing I've done has been directly through VDU2, etc. or through creating an HTM document and then executing that file. So doing this with @prthdc% is new to me. However, I'll have a go and see what I can do. Any pointers would be appreciated, though.

Thanks

Matt
Re: Print Preview
Post by admin on May 23rd, 2013, 09:06am

on May 23rd, 2013, 05:31am, Matt wrote:
Any printing I've done has been directly through VDU2, etc.

In that case you might be able to do the Print Preview by creating a memory DC compatible with @prthdc%, temporarily setting @prthdc% to your temporary DC, doing the normal print output, and then restoring @prthdc% to its previous value (followed by blitting the temporary DC to your preview window of course).

It's not something I've tried, but it sounds relatively straightforward and also quite interesting. Maybe if it can be made to work it could be developed into a BB4W 'print preview' library. If that's something you would like to attempt I'm sure the BB4W user community would be extremely grateful!

Richard.