I'm trying to retrieve some data from a service, and I'm working with a mutablelist to store the objects. The problem is that I need to add the retrived data to this mutablelist, but addAll says me that the type is mismatched.
the problem here is nullability. you are passing a nullable collection( your MutableList) to a not-nullable collection. one approach is to mark the MutableList as not-nullable by adding !!
at the end of your nullable Mutablelist.
to give you some idea, check this snippet code:
var collection:Collection<String> = emptyList()
var myList:MutableList<String>? = mutableListOf()
collection = myList!!