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How to assign DataPipe to subreport in runtime...

edited September 2002 in Subreports
I have just downloaded ReportBuilder, so I'm new to it.

I have to load report from a database, create local datasources,
datapipelines and connect the neccessay stuff (Dataseta are on the form).
Report has a subreport and I don't know how to assign datapipe to the
subreport in code!
How do I access subreports on report in code?
How do I create Field links in DataPipelines in code?

Thanks.
Ivan

PS
And yes, I'm using Borland Builder (C++).

Comments

  • edited September 2002
    You can access a subreport datapipeline like this

    TppSubreport.Report.Datapipeline. The subreport class wraps a report object
    so that it effectively is an embedded report.

    To find the subreport, you can perform a report object loop. In the object
    loop, check to see if the component is a TppSubreport. By passing a report
    object in the function, you can recursively look for subreports by passing
    Subreport.Report when you find a subreport:


    procedure TForm1.AssignFontToReport(aFont: TFont; aReport: TppCustomReport);
    var
    liBand: Integer;
    liObject: Integer;
    lObject: TppComponent;
    begin

    for liBand := 0 to aReport.BandCount-1 do
    begin
    for liObject := 0 to aReport.Bands[liBand].ObjectCount-1 do
    begin
    lObject := aReport.Bands[liBand].Objects[liObject];

    if lObject is TppSubreport then
    AssignFontToReport(aFont, TppSubreport(lObject).Report)

    else if lObject.HasFont then
    lObject.Font := aFont;

    end;
    end;

    end;

    Are you using master field links to perform master detail linking as it is
    done in DADE by using a single query for all detail records, instead of
    letting Delphi fire a detail query every tim ethe master record changes?
    Here is a demo of this approach:

    http://www.digital-metaphors.com/tips/MagicMasterDetail.zip

    Below is an article on how to create the links at runtime:


    Cheers,

    Jim Bennett
    Digital Metaphors

    ---------------------------------------------------------
    Tech Tip: Define Master/Detail DataPipeline Links in Code
    ---------------------------------------------------------

    Defining a Master/Detail relationship for a DataPipeline
    requires that the detail pipeline have the
    following properties defined:

    1. MasterDataPipeline

    2. MasterFieldLinks


    At Delphi design-time you can use the object inspector
    and the DataPipeline's FieldLinks editor to define
    the master/detail relationship.


    The following example illustrates how to define the
    master/detail relationship dynamically at run-time.


    var
    lFieldLink: TppMasterFieldLink;


    begin

    {define the master/detail pipeline relationship}
    plDetail.MasterDataPipeline := plMaster;

    {create a new field link }
    lFieldLink := TppMasterFieldLink.Create(nil);

    lFieldLink.Parent := plDetail;

    {assign the detail field name}
    lFieldLink.DetailFieldName := 'CustNo';

    {assign the master field name}
    lFieldLink.MasterFieldName := 'CustNo';


    end;


    Note: The DataPipeline linking requires the records in the detail dataset to
    be ordered by the linking fields. In the above example, the detail data must
    be ordered by CustNo.


    --
    Tech Support mailto:support@digital-metaphors.com
    Digital Metaphors http://www.digital-metaphors.com


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