Convert Array<String> to ArrayList<String>

Issue

How do I convert Array<String> to ArrayList<String> in Kotlin?

var categoryList : ArrayList<String>?=null
val list = arrayOf("None", "ABC")
categoryList = ArrayList(Arrays.asList(list))

I receive this error:

Error

Type inference failed. Expected type mismatch: inferred type is kotlin.collections.ArrayList<Array<String>!> /* = java.util.ArrayList<Array<String>!> */ but kotlin.collections.ArrayList<String>? /* = java.util.ArrayList<String>? */ was expected

Solution

You may be interested in toCollection to add the elements to any collection you pass:

categoryList = list.toCollection(ArrayList())

Note that to fix your specific problem you just need the spread operator (*). With the *-fix applied it would have worked too:

categoryList = ArrayList(Arrays.asList(*list))

Answered By - Roland