Please refer my answer for the following https://forum.mendix.com/link/questions/102057 (for *-* association)
For selecting the multiple objects through self reference, you have build a custom logic with the helper object.
That helper object (ContentHelper) can be connected with your Content entity with 2 association,
Use new data view inside your Content object with microflow as datasource returning the ContentHelper Object (create/retrieve activities)
Configure the BootStrap MultiSelect Dropdown inside the new dataview ContentHelper (by using the *-* with Content objects)
Hi Amit, as Ananthi’s answer suggests, your domain model needs to look like this to use the Bootstrap MultiSelect:
You need to have a BaseEntity with a reference set that points to SelectableThing. When you’re selecting items from the dropdown, the items you select will be stored as references in this reference set.