On Wed, 3 Jan 2024 13:00:10 +0100 (CET) Michael Van Canneyt via fpc-pascal <fpc-pascal@lists.freepascal.org> wrote:
> > > On Tue, 2 Jan 2024, Pique7 via fpc-pascal wrote: > > > On Tue, 2 Jan 2024 00:02:35 +0100 (CET) > > Michael Van Canneyt via fpc-pascal <fpc-pascal@lists.freepascal.org> wrote: > > > >> > >> > >> On Mon, 1 Jan 2024, Pique7 via fpc-pascal wrote: > >> > >>> Hello everyone, > >>> > >>> I have already asked this and related questions in the Lazarus Forum. > >>> > >>> I want to improve FPReport in order to use it for my project - if > >>> possible. > >>> Some features are missing for this, e.g. automatic splitting of text > >>> across two or more pages. > >>> > >>> As far as I can judge, the current development status of FPReport does > >>> not really allow me to extend it without modifying the original classes. > >> > >> Why do you think so ? > > > > Thanks for your reply. I am not sure whether I have defined the problem > > correctly from my point of view. I have tried both FPReport and > > LazReport. LazReport is able to create page breaks within a band > > automatically (though not always correctly calculated). This is traceable > > by viewing the source code of LazReport. I haven't found anything similar > > in the source code of FPReport and thus considered to implement it myself. > > But I haven't found a straightforward solution. > > There is no straightforward solution if you wish to break a memo. > > The layouter is not equipped for splitting bands. > > >>> What approach do you suggest? Would this be feasible/reasonable at all? I > >>> ask this because I am new to Lazarus and FPC. I come from Delphi 2007 ... > >> > >> If you ask me, it's perfectly doable without any changes. > >> > >> There is a demo that shows how to print a text by splitting it in lines, > >> and > >> simply printing a band per line. That will have the same effect as what you > >> seem to need. Basically, it means using a TStringList as a data source > >> for a (sub)band instead of using it as the text of a single memo. > > > > Unfortunately I couldn't find the demo program you mention. I know the > > fcl demos in "source\packages\fcl-report\demos". Admittedly I haven't > > examined every single unit yet. Most of the demo reports get the data > > from a TStringList. Is it this what is meant? > > Yes. Normally you'll be using a dataset-based "data loop" (TFPReportData). > > But the data loop can be an event-based loop, which uses a TStringList to > define the items in the loop. (an instance of TFPReportUserData is used for > this) > > >> What you may need to do is to split the text "correctly" over the lines of > >> the > >> TStringList, but that should be easily doable. All you need is a function > >> to > >> calculate the length of the text. > >> > >> I think this is perfectly doable without any changes to the original code. > > > > Okay, probably you're right and I think I understand the basic idea but I > > still don't know how to transfer it to my case. I have a table with > > several columns containing multiline text. The data comes from a TDataSet > > descendent. If one the cells (Memo) content is to large to fit on the > > current page, the whole band should be split at the correct position and > > continued on the next page, e.g.: > > > > [PAGE 1 - DATABAND 1 (bottom of page)] > > COL 1-1 COL 2-1 > > COL 1-2 COL 2-2 > > COL 1-3 COL 2-3 > > > > [PAGE 2 - DATABAND 1 (continued)] > > COL 1-4 COL 2-4 > > COL 1-5 > > > > I also have one report with one column containing richtext (RTF). I doubt > > that the TStringList solution will be helpful in this case. > > If RTF is a requirement, in that case you can desist your efforts: > RTF is not supported in FPReport. A limited subset of html is. > > I don't know if RTF is supported in lazreport. Maybe on windows it is. > > FPC comes with an RTF parser, but it would require a large amount of work to > integrate that in FPReport. RTF is a huge subject. > It would be a nice addition, no doubt. > > > > > So in a nutshell, I think I need a function like "Continue (data) band on > > the next page if remaining space is insufficient". > > At the moment, I don't see how to create this function. > IMO It would require a major rewrite of the layouter to introduce this. > > > If you still think > > your suggested approach is suitable, please let me know. Maybe it is > > obvious, but at the moment it seems that I don't make any progress. > > Disregarding the RTF for a moment, you'd need to save the contents of the > text fields in a TStringlist instance in the 'afterscroll' event of the > dataset. > > This instance can then be used to create a data loop for a sub band > (using TFPReportUserData). > The band connected to the dataset (the master band) would not print anything. > Instead, the child band will print the cell content line by line and split it > over pages. > > From your drawing, it is not quite clear how you construct your columns, > if you're using columns, I'm not sure how the band will behave. > > Michael. Thanks again for your suggestions. I haven't tried it yet but now I've got the idea. Your are so optimistic but I still fear all the things which might make troubles in a more complex report with grouping, master/detail data, calculations, layout adjustments, HTML tags, table borders etc. However, finally I've tried to extend/improve the original FPReport classes and now I really have a FPReport version that supports band splitting for simple FPReportMemos. I was not able to implement this using inheritance - I've had to change the original source code in the FPC folder. Without any doubt there are still many bugs in my FPReport. But if you want a copy, let me know! :-) > _______________________________________________ > fpc-pascal maillist - fpc-pascal@lists.freepascal.org > https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
