I have a requirement to have a textbox in which the user can enter more than one value.
Example: Something like "Hobbies" where the user can enter more than one hobby in the text box. If the user wants to add a new hobby, then he//she should be able to click on a + sign to get another text box just below the current one (something like a multifield textfield in dialogs).
Is it possible using Adaptive forms? Also, how will the values be stored in the repository?
Can you please try using a repeatable panel with max occurrences set to some high value. That panel should contain your field.
If you use accordion layout for the panel, you would get '+' button by default.
So the node structure would be a panel having one children.