Multi - Select Combo Based on API output - Constellation 24.2

[RahulBilove]

Has anyone used Multi Select combo box for fetching the data from API, without managing the data locally?
Considering the data will be unique for every case type, and may change in future as per the user journey

[JayachandraSiddipeta]

Hi @RahulBilove

You can check the below post for reference

Constellation (25) Autocomplete for external systems

Hi, Is there any way to have the OOTB autocomplete - either with the Single Page data reference, or single text property, datapage on property, pxAutocomplete approach - refresh/execute an API call on each keystroke? We have a requirement where we are querying an external system with a lots of records, so as we type in what we are looking for, we want to send a new request to a REST service after each new letter, or something similar. Like how you would expect the google maps search to work. R…

If the combo box entries are specific to your case, then pass parameters to the data page and ensure that your external api supports it and returns appropriate records.

For multi select combo boxes, you need to have single lookup data page as well. So ensure to configure it accordingly.

Hope this helps and let us know if you have any further queries

Refer to the below post for more details

Managing external system of record through REST with CRUD actions in Pega Constellation

https://players.brightcove.net/1519050010001/default_default/index.html?videoId=6370623183112 Why Effective data management starts with easy CRUD actions regardless of system of record. Pega Constellation makes it easy to perform Create, Read, Update and Delete through REST connectors. Article presents configuration steps, allowing for fast integration and management of external records, and all that can be done in App Studio by a Citizen Developer. You save time and resources while maintainin…

Regards

JC

[RahulBilove]

@JayachandraSiddipeta

For multi select combo boxes, you need to have single lookup data page as well. So ensure to configure it accordingly.

“For multi select combo boxes, you need to have single lookup data page as well. So ensure to configure it accordingly.”

Does that mean we need to have one Data Type(Build on Concrete class), to store the data and then use as primary Data Page for the lookup and then place another API based Data Page for muti select combo box?

[JayachandraSiddipeta]

Not for storing data. To hold the data mapping. You can create a abstract data class. When you create the data type. Select the storage as Later rathern Now. This will only create the class. Setup the integration. You will have the List data page. Additionally create a single data page with alternate storage option checked and setting the linked field in the parameters. For sourcing the data use a DT and loop through the entries of list page and return the matched entry.

Refer to the below links for more details

Constellation Architecture - How to create abstract Data- Classes

@DanieleD9965 You can add your data calss to the application definition - Cases and Data - Under Data class section. The recommendation is to create data class through App Studio. Define Data source - Later - this will not create a DB table

Data reference for an Abstract class in Configure View

@phanid79 thanks for the detail this helps. Modular approach So first up, building reusable data objects to be reused by different applications. I have seen this used with great effect using a modular approach - in this case Application B is built on Application A and can directly reuse the data object as defined in app definition. I have seen this implemented in both Traditional and Constellation Apps, so there is no problems here - it leans into how Pega OOTB App Definition and Inheritance w…

Hope this helps

[RahulBilove]

@JayachandraSiddipeta

the parameters. For sourcing the data use a DT and loop through the entries of list page and return the matched entry.

The approach worked. Thanks @JayachandraSiddipeta for the assistance.

[RahulBilove]

@JayachandraSiddipeta

For multi select combo boxes, you need to have single lookup data page as well. So ensure to configure it accordingly.

The list is populating correctly, however when we select the record, it fails. Is there any additional configuration we need to make. Please assist.

Inference: What I understood is that the unique key is not present for the Abstract class so it might be breaking internally while matching the ID(Refence field) with the records at the class.

[Marc_Alderman]

For selection to work correctly when using a Data Reference, there must be a unique key that can be used to resolve the selected value(s) back to an individual record.

A Data Reference is always configured with a single‑record lookup data page, regardless of whether the field is configured for single‑ or multi‑select. This single data page is responsible for resolving an individual item based on its key.

In a typical (OOTB) Data Reference setup:

• The list data page is used purely to source the options displayed in the UI control (for example, the values shown in a multi‑select).

• The single data page configured on the Data Reference itself is what Pega uses to resolve each selected item, using the key value from the selection.

So while the list data page drives what the user can choose from, the actual selection logic depends on the single‑record data page being able to uniquely look up each selected item. If the key is not unique or not consistently returned by both data pages, selection (especially in multi‑select scenarios) will not work as expected.

[JayachandraSiddipeta]

Yes, you need to setup a primary key for your data type class and use that for your single record page.

Regards

JC