Dropdown with Spinner & AutoCompleteTextView

 <com.google.android.material.textfield.TextInputLayout

style="@style/Widget.Material3.TextInputLayout.OutlinedBox.ExposedDropdownMenu"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
<AutoCompleteTextView
    android:id="@+id/autoCompleteTv"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:inputType="none"
    />

object AutoCompleteHelper {

    fun <T> initializeAutoCompleteTextView(
        context: Context,
        autoCompleteTextView: AutoCompleteTextView,
        data: List<T>,
        displayFunction: (T) -> String,
        onItemSelectedListener: (position: Int, selectedItem: T) -> Unit
    ) {
        val adapter = ArrayAdapter(context, android.R.layout.simple_spinner_dropdown_item, data.map(displayFunction))
        autoCompleteTextView.setAdapter(adapter)

        autoCompleteTextView.setOnItemClickListener { _, _, position, _ ->
            val selectedItem = data[position]
            onItemSelectedListener(position, selectedItem)
        }
    }

    fun <T> setAutoCompleteSelectionByValue(
        autoCompleteTextView: AutoCompleteTextView,
        data: List<T>,
        valueToSelect: T,
        displayFunction: (T) -> String = { it.toString() }
    ) {
        val position = data.indexOf(valueToSelect)
        if (position >= 0) {
            autoCompleteTextView.setText(displayFunction(data[position]), false)
        }
    }



    fun setAutoCompleteSelectionByIndex(
        autoCompleteTextView: AutoCompleteTextView,
        data: List<String>,
        index: Int
    ) {
        if (index >= 0 && index < data.size) {
            autoCompleteTextView.setText(data[index], false)
        }
    }
}

object SpinnerHelper {

    fun <T> initializeSpinner(
        context: Context,
        spinner: Spinner,
        data: List<T>,
        displayFunction: (T) -> String,
        onItemSelectedListener: (position: Int, selectedItem: T, view: View?, id: Long) -> Unit
    ) {
        val adapter = ArrayAdapter(context, android.R.layout.simple_spinner_item, data.map(displayFunction))
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
        spinner.adapter = adapter

        spinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
            override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
                val selectedItem = data[position]
                onItemSelectedListener(position, selectedItem, view, id)
            }

            override fun onNothingSelected(parent: AdapterView<*>?) {
                // No action needed here
            }
        }
    }



    fun <T> setSpinnerSelectionByValue(
        spinner: Spinner,
        data: List<T>,
        valueToSelect: T
    ) {
        val position = data.indexOf(valueToSelect)
        if (position >= 0) {
            spinner.setSelection(position)
        }
    }



    fun setSpinnerSelectionByIndex(spinner: Spinner, index: Int) {
        if (index >= 0 && index < spinner.adapter.count) {
            spinner.setSelection(index)
        }
    }
}