i had the following error while trying to implement Collection _select
in making a drop down of items in two models
You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.map
my code in the views is as follows:
<%= collection_select("category", "category_id",@categorys, "id",
I need guidance on how to properly do this, thanks for the support