Confirmation on Using "Parent" in Declare Expressions for Accessing Parent or Sibling Pages in Constellation
Context: We are implementing a PoC using Constellation views that requires real-time calculations via Declare Expressions and forward chaining. The goal is to eliminate the need for custom actions or buttons.
Clipboard Structure: The target property (.PeriodicRate) and the source property (.Rate) are sibling embedded pages under a parent page (Quotation).
pyWorkPage.Quotation (MyOrg-LoanQuot-Data-Quotation)
├── Calculation (DE Target: .PeriodicRate)
└── SelectedOption (Source: .Rate)
Requirement: The Declare Expression in Calculation (Class MyOrg-LoanQuot-Data-Calculation) must be able to declaratively reference and automatically listen for changes in SelectedOption.Rate.
Failed Attempts:
Context: We are implementing a PoC using Constellation views that requires real-time calculations via Declare Expressions and forward chaining. The goal is to eliminate the need for custom actions or buttons.
Clipboard Structure: The target property (.PeriodicRate) and the source property (.Rate) are sibling embedded pages under a parent page (Quotation).
pyWorkPage.Quotation (MyOrg-LoanQuot-Data-Quotation)
├── Calculation (DE Target: .PeriodicRate)
└── SelectedOption (Source: .Rate)
Requirement: The Declare Expression in Calculation (Class MyOrg-LoanQuot-Data-Calculation) must be able to declaratively reference and automatically listen for changes in SelectedOption.Rate.
Failed Attempts:
| Attempt | Expression | Result |
| Relative Reference | .Parent.SelectedOption.Rate |
Fails on save with an invalid reference error. |
| Absolute Reference | pyWorkPage.Quotation.SelectedOption.Rate |
Fails validation ("@baseclass.Quotation is undefined") and refreshing is unreliable. |
Exportar a Hojas de cálculo
Explicit Query to Pega Support:
Given the validation restriction when using .Parent and the requirement for declarative calculations in Constellation:
Is it technically possible and supported by Pega for a Declare Expression on an embedded page to declaratively access a property on a sibling embedded page, thereby enforcing forward chaining?
If the answer is No, what is the recommended Pega design pattern to achieve live calculations between data located on sibling pages within a Constellation environment, while minimizing the use of manual Activities or Data Transforms?