VLF-ONE Object to Object Navigation and Relationships

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jyoung
Posts: 694
Joined: Thu Jan 21, 2016 6:43 am
Location: Oklahoma City, OK USA

VLF-ONE Object to Object Navigation and Relationships

Post by jyoung »

So we finally got our first VLF-ONE Application (one application with one object, with 5 Filters and 6 commands) in Production "beta" testing. :D
Huge thanks to the members of this forum that patiently help me get stuff figured out.

We are looking at our next object(s) and I am trying to figure out the best way to handle / organize the them.

Our current object centers around a "client". Now a single client can have multiple invoices and each invoice has multiple "time cards". A time card a period of time that an individual worked, what their pay rate is, the amount paid and the check number that used to pay the individual, etc.

Modeling this nested relationship (Client -> Invoice -> Time Card) is throwing me off.

How would you organize this in VLF-ONE?

Would you create three separate objects each with their own filters or commands? I could potentially see each one having value on its own. I've read about switching objects but I don't see how to "pass data" to another object. For example, I have selected Client ABC. I want to see their Invoices so I need to pass Client ABC's identifiers to the Invoice object.

I was thinking about making an "Invoices" command that would show a list of Invoices. When an Invoice is selected, I need to trigger something else to show the Time Cards. This I thought would be a hidden "By Invoice" Time Card filter, but I still need to get the Invoice Id to the filter. I could create a shared state object that the Invoice command would set the identifier and the hidden filter would read.

Does that make sense? Is that the "LANSA" way of handling a situation like this?

Edit
Reviewing the "Children" example application. Based on that example, I would still create the Invoice and Time Card commands however I would model the relationship through the instance list. In my comment above, I was trying to show model the relationship through commands. I could create filters for Invoices like "By Client Name" or "By Client Number" and filters for Time Cards like "By Invoice Number" etc.
MarkD
Posts: 692
Joined: Wed Dec 02, 2015 9:56 am

Re: VLF-ONE Object to Object Navigation and Relationships

Post by MarkD »

Business objects in the VLF are meant to be ‘business instruments’ as seen from the end user perspective.

They are not meant to be directly reflective of the nature or structure of any underpinning data base tables, table relationships, data models, entities, etc.

I think that the VLF ‘child’ business object concept, originally created to support their automatic visualization in tree like structures, is somewhat superseded now by more modern ways to visualize them.

For example in the shipped demo expenses are children of employees but they are not defined to the VLF as child objects…..
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