I have an array filled with mixed user Inventory objects.
the objects have an object.name attribute. when I iterate through the array it will already be sorted by name. if we looked at obj.name in the array it would have this structure
[ball,ball,monkey,monkey,sausage]

1. I would like to loop through the array.

2. get all elements with common name attribute and create a new array out of those elements.

any suggestions there? bonus points if we can name the array the object.name attribute. I am using Kotlin.

Here is the code/thoughts I have to start, any other suggestions are appreciated if this is not doable

private fun sortElements(){
        val temp = userstuff[0].name //but what if they only have 1 of these names.. doesnt work
        userstuff.forEach { element ->
            if(temp == element.name)
             we have another item with same name put in appropriate array
             else{
                  new array 
                  loop
        }

CodePudding user response：

If I'm understanding your use case correctly, you should be able to do something like this:

private fun sortElements(input: List<Stuff>) = input.groupBy { it.name }

The idea here is that you take each element and put it into a Map where the key is the name value and the values are a List of your objects.

To give an example here, let's say I have a data class called Stuff:

data class Stuff(
    val name: String,
    val otherField: Int,
)

and test data that looks like this:

val userStuff = listOf(
    Stuff("ball", 242),
    Stuff("ball", 11),
    Stuff("monkey", 848),
    Stuff("monkey", 455),
    Stuff("sausage", 836),
)

Calling the function above would give a result like this (this would be a Map<String, Stuff>, I just printed it out so you can see what's in there):

{
    ball=[
        Stuff(name=ball, otherField=242),
        Stuff(name=ball, otherField=11)
    ],
    monkey=[
        Stuff(name=monkey, otherField=848),
        Stuff(name=monkey, otherField=455)
    ],
    sausage=[
        Stuff(name=sausage, otherField=836)
    ]
}