How to reference existing entity using Inline Entity Form?

Question

I'm using Entity Reference to create tasks in lists - both tasks and lists are content type, list contains multivalue Entity Reference to task. Because most tasks belong to only one list, it was only natural to use Inline Entity Form.

Problem is most - there are some tasks that needs to belong to many lists.

Module's docs says:

Existing entities can also be referenced.

That would do the trick. My question is very simple: How do I do that? Only button I see is "Add new node", and it opens node creation form. What should I do to see "Add existing node"?

Answer 1

To add more clarity to the answer:

• In Edit tab, check "allow users to select existing nodes" as shown below

• In your content creation form, you could find two buttons: Add New Node and Add Existing Node as shown below

Answer 2

Inline Entity Form settings are in the Edit tab, not the Field settings one. Once I realized this, it was easy to find Allow users to add existing nodes checkbox. Once it's checked, there are two buttons on field's list: a button for creating a new reference, and one for referring the existing nodes.

Answer 3

The important yet confusing step I observed when wanting to add an existing term, for example, was to make sure you select "Inline entity form - Multiple values" not single values (see https://www.drupal.org/node/2134035). The current patch needs community review.