TaskAsync not running

I'm trying to fill a Spinner by clicking a button. Have the function run through an AsyncTask so it doesn't slow down the app.

MainActivity.java

package com.example.sigeapp;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

private ArrayList<String> arrList_obras;
private ArrayAdapter<String> arrAdapter_obras;
private Spinner spinner_obras;
private Button button;

CONEXIONES conexiones = new CONEXIONES();
private MitareaAsincrona mitarea;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    spinner_obras = findViewById(R.id.spinner_prueba);
    button = findViewById(R.id.button);

    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            mitarea = new MitareaAsincrona();
            mitarea.execute();
        }
    });

}

private void tareaLarga()
{
    arrList_obras = conexiones.SELECT("SELECT * FROM OBRAS", getApplicationContext(), 3);
    arrAdapter_obras = new ArrayAdapter<String>(getApplicationContext(), R.layout.spinner_drawable, arrList_obras);
    spinner_obras.setAdapter(arrAdapter_obras);

}


private class MitareaAsincrona extends AsyncTask<Void, Void, Boolean> {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        Log.e("AsyncTask", "onPreExecute");
    }

    @Override
    protected Boolean doInBackground(Void... params) {
        try {
            Log.v("AsyncTask", "doInBackground");
            tareaLarga();
            return true;
        } catch (Exception ex) {
            return false;
        }
    }

    @Override
    protected void onPostExecute(Boolean result) {
        if (result) {
            Log.v("AsyncTask", "onPostExecute");
            Toast.makeText(MainActivity.this, "Tarea finalizada!", Toast.LENGTH_SHORT).show();
        }
    }
}

}

The function tareaLarga()is responsible for loading the data into Spinnerit and it works fine. If I put a Toastin the onClickdel buttonis before or after mitarea.execute()it Toastis shown but the AsyncTask does not work, I realize this by the 3 logs and the Toast that I put, none of them do anything. What am I doing wrong?

Update

If the Asynctask runs but does not load the Sipnner. the Toast and the logs if they are executed