Binding adapter for Android Spinner view when using https://github.com/Aidanvii7/Toolbox

spinner_item.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/text1"
    android:singleLine="true"
    android:layout_width="match_parent"
    android:paddingStart="20dp"
    android:layout_height="40dp"
    android:ellipsize="marquee"
    android:gravity="center_vertical"
    android:textAlignment="inherit"/>

SpinnerBindingAdapters.kt

import android.view.View
import android.widget.AdapterView
import android.widget.ArrayAdapter
import android.widget.Spinner
import androidx.databinding.BindingAdapter
import androidx.databinding.InverseBindingAdapter
import androidx.databinding.InverseBindingListener
import com.aidanvii.toolbox.databinding.getTrackedValue
import com.aidanvii.toolbox.databinding.trackValue

@InverseBindingAdapter(attribute = "selectedItem", event = "selectedItemAttrChanged")
internal fun <T : Any> Spinner.getBoundSelectedItem(): T? =
    getTrackedValue<List<T>?>(R.id.list_items)?.getOrNull(selectedItemPosition)

@BindingAdapter("selectedItem")
internal fun <T : Any> Spinner.setBoundSelectedItem(selectedItem: T?) {
    if (selectedItem != null && selectedItem != getSelectedItem()) {
        val items = getTrackedValue<List<T>?>(R.id.list_items)
        items?.indexOf(selectedItem)?.let { itemIndex ->
            if (itemIndex >= 0) {
                setSelection(itemIndex)
            }
        }
    }
}

@BindingAdapter(
    "items",
    "selectedItemAttrChanged", requireAll = false
)
internal fun <T : Any> Spinner.bind(
    items: List<T>?,
    selectedItemAttrChanged: InverseBindingListener?
) {
    if (items != null) {
        trackValue(
            newValue = items,
            valueResId = R.id.list_items,
            onNewValue = {
                adapter = ArrayAdapter(
                    context,
                    R.layout.spinner_item,
                    items
                ).apply {
                    setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
                }
                onItemSelectedListener = selectedItemAttrChanged?.run {

                    object : AdapterView.OnItemSelectedListener {
                        override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
                            onChange()
                        }

                        override fun onNothingSelected(parent: AdapterView<*>?) {
                            onChange()
                        }
                    }
                }
            },
            onOldValue = {
                adapter = null
                onItemSelectedListener = null
            }
        )
    }
}