Drop down list error in mobile when performing a create record action

Question

I am creating an MVP that requires users to add specific records for sites and buildings while using the mobile app (offline and online). My current roadblock is when I'm creating a new building record that needs to be associated with a specific site. In the create new building interface, there is a site drop down list that a user can select before adding a building name/number. For testing I have two ways to initiate the create building record action. The first way is through the building record list site page (using the Record List Action to initiate the process), and the second way is through a site page that initiates the create building action. In the latter setup, when selecting a site I receive an "Invalid Rule UUID field:..." for line 13 in the picture provided. 
 I appreciate any help or insight into this issue. Thanks!

jasonk6935 · Answer

Hi, 
 We were able to fix the issue by doing the following: 
 
 Create Data Stores and CDTs for the Site and Building tables
 
 This included creating a constant (AMS_DSE_SITES) to use in a queryEntity vs calling an expression rule using queryRecordType.
 
 Since this needs to work offline, using CDTs instead of RecordTypes was key

Create a rule input for the Building CDT (e.g. ri!building) 
 Assigned the value of the local!siteList variable, which drives the drop-down choices and choice values, to a queryEntity that references the AMS_DSE_SITES constant
 
 Set the refreshAlways to false

Change the values and saveIntos for the site drop-down and other fields to the Building CDT fields (e.g. ri!building.siteId, etc.) 
 Update the process model
 
 Ensured process variables include the Building CDT 
 Changed Write Record node to Write to Data Store Entity 
 Ensured activity chaining was turned on from the start node to the Write to Data Store Entity 
 Within the Write to Data Store Entity under Data:
 
 Inputs:
 
 Within the Data Store Entity I referenced the Building CDT 
 Added a new Building input (type = the Building CDT; value = Building process variable)

Outputs:
 
 Within Results, change the Stored Values target to the Building process variable (should save back all data including the newly generated PK for the building table).

I hope this is helpful for anyone needing to develop for offline or online mobile.