Cara Membuat Spinner Android Studio

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20sp"
        android:layout_centerHorizontal="true"
        android:text="@string/contoh_spinner"
        android:textSize="25sp"
        android:textStyle="bold"/>

    <Spinner
        android:id="@+id/spinner"
        android:layout_width="200sp"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView"
        android:layout_marginTop="20sp"
        android:layout_centerHorizontal="true"/>

</RelativeLayout>

package com.example.spinner;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {

    String[] cemilan = {"Bakso", "Pempek", "Kue Putu"};

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Spinner spinner = (Spinner)findViewById(R.id.spinner);
        spinner.setOnItemSelectedListener(this);

        ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_spinner_item, cemilan);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(adapter);
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        Toast.makeText(this,
                cemilan[position], Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
    }
}