How to update a SharePoint Multi-value Lookup Column using a PowerApps Combobox?

Question

I have a primary SharePoint list which is connected to a customised PowerApps form for data entry. Inside this form, I have added an additional multi-select Combo-box, which displays values from a secondary SharePoint reference list. The main intent is for the user to select 1 or more values from the secondary reference list Combobox, and then have all the selected values inserted into the Lookup column attached to the primary SharePoint list record.

The issue is that when I save the primary record in PowerApps, it only inserts a single value back into the multi-value Lookup column (in the primary list). I can confirm that the Lookup column's "Allows multiple values" option is checked.

I was hopeful I could just use cboReferenceList.SelectedItems in the DataCard's update properties, but alas it doesn't seem to work.

How can I ensure all my Combo-box values are saved back to my SharePoint Lookup Column?

Answer 1

I found the following from https://powerusers.microsoft.com/t5/Building-Power-Apps/How-to-filter-choices-on-Combobox/td-p/101436. I was able filter the original Lookup column on the PowerApps form, essentially removing the need for a seperate filtered combo-box:

Filter(Choices([@PrimaryList].LookupColumnName),Value in Filter(ReferenceList,ReferenceFilter.Value="Yes").Title)