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JIT or custom pipelines without field definitions

edited August 2002 in Datapipelines

I'm currently evaluating rbuilder for a project involving a MDA framework
(Bold for Delphi www.boldsoft.com).

As the Bold framework provides an object model, and object traversals with
OCL expressions, I don't want to use field definitions.

I did some tests using the JIT Pipeline, but it wouldn't work without
defining fields. I tried it, specifying fieldnames in data controls. The JIT
Event for GetFieldValue was correctly triggered with my expression from the
control, but the data wasn't displayed until I defined the fields on the JIT

How deep are field definitions integrated in the reporting code ? Would it
be possible to derive a custom Pipeline that doesn't need field definitions
Can master/detail bands be realized without field definitions, just by
specifying a master pipeline and a link expression ?

thanks for answers

Samuel Iseli


  • edited August 2002
    You need field definitions in order to create a report with data fields.
    This is the only way that the report engine will know how to traverse
    records. If you have no fields, then you have no report data to generate.
    However, you can disconnect the report from the datapipeline. Set
    Report.Autostop to false. Then the detail band will generate forever. You
    could use this approach if you have no data but want to print detail bands
    for some number of iterations. You can set Autostop to true and the report
    will stop generating detail bands.


    Jim Bennett
    Digital Metaphors

  • edited August 2002
    Hi Jim

    I see that a pipeline is needed for report data traversal, but why can't the
    report engine just pass 'fieldnames' it encounters in datafields on to the
    pipeline and print the result it gets back ?


    Samuel Iseli
    vertec ltd

  • edited August 2002
    The report data aware controls require a field to be connceted to on the JIT
    pipeline. Certainly, you can define zero fields at design time and create
    fields on your JIT pipeline at runtime. This is probalby the way to go on
    this one.


    Jim Bennett
    Digital Metaphors

  • edited September 2002
    "Samuel Iseli" wrote in news:3d69fd98@dm500.:

    Does the Bold framework provide a way to get an object's properties at run
    time? If so you can create a custom pipeline that uses it to create the
    necessary fields.

    We have an ObjectSource that provides this information for our object
    hierachy as well as methods to get and set property values. ObjectSource
    users have no knowledge of the underlying object.

    I wrote an ObjectSource aware custom pipeline with an ObjectSource
    property. When this property is set, it uses the ObjectSource's property
    list to create fields. I remember that there was some non-obvious but
    easy things required for the fields to be created property.

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