AddressesSpinnerAdapter.kt

class AddressesSpinnerAdapter(
    context: Context,
    textViewResourceId: Int = android.R.layout.simple_spinner_item
) : ArrayAdapter<AddressesSpinnerItem>(context, textViewResourceId) {

    var values: ArrayList<AddressesSpinnerItem> = arrayListOf()
        set(value) {
            field.clear()
            field = value
            notifyDataSetChanged()
        }

    var selectedPosition = 0

    init {
        setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
    }

    override fun getCount() = values.size

    override fun getItem(position: Int) = values[position]

    override fun getItemId(position: Int) = position.toLong()

    override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {
        val title = super.getDropDownView(position, convertView, parent) as TextView
        updateView(title, position)
        return title
    }

    override fun getDropDownView(position: Int, convertView: View?, parent: ViewGroup): View {
        val title = super.getDropDownView(position, convertView, parent) as TextView
        updateView(title, position)
        return title
    }

    private fun updateView(title: TextView, position: Int) {
        title.text = getItem(position).title
        title.setTextColor(
            ContextCompat.getColor(
                title.context,
                if (position == selectedPosition) R.color.colorDarkPeach else R.color.colorBlack
            )
        )
    }
}

data class AddressesSpinnerItem(val id: Int, val title: String?, val address: Address?)

Fragment.kt

private fun setupSpinner() {
        spinnerAddresses.adapter = addressesSpinnerAdapter
        spinnerAddresses.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {

            override fun onItemSelected(p: AdapterView<*>?, v: View?, position: Int, id: Long) {
                addressesSpinnerAdapter.selectedPosition = position
                addressesSpinnerAdapter.notifyDataSetChanged()

                viewModel.onAddressSelected(position)
            }

            override fun onNothingSelected(view: AdapterView<*>?) = Unit
        }

    }

layout.xml

<Spinner
            android:id="@+id/spinnerAddresses"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginStart="@dimen/default_margin_16"
            android:layout_marginEnd="@dimen/default_margin_16"
            android:spinnerMode="dropdown"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

viewmodel.kt

val addressesItems = it.addresses
                ?.map { AddressesSpinnerItem(it.mappingId ?: 0, it.caption, it) }
                ?.toMutableList()
                ?.apply { add(0, AddressesSpinnerItem(DEFAULT_ALL_ADDRESSES_ID, "Все квартиры", null)) }