BaseAdapter.kt

abstract class BaseAdapter<T>(
    private var itemSimilarityPredicate: (T, T) -> Boolean,
    private var contentSimilarityPredicate: (T, T) -> Boolean
) : ListAdapter<T, BaseAdapter<T>.DataBindingViewHolder>(object : DiffUtil.ItemCallback<T>() {
    override fun areContentsTheSame(
        oldItem: T,
        newItem: T
    ) = contentSimilarityPredicate.invoke(oldItem, newItem)

    override fun areItemsTheSame(
        oldItem: T,
        newItem: T
    ) = itemSimilarityPredicate.invoke(oldItem, newItem)
}) {
}

PeopleAdapter.kt

class PeopleAdapter : BaseAdapter<Person>(
    { oldItem, newItem -> oldItem == newItem },
    { oldItem, newItem ->
        oldItem.firstName == newItem.firstName && oldItem.lastName == newItem.lastName
    }) {

    override fun getItemViewType(position: Int): Int {
        return R.layout.item_person
    }
}