How to populate a ListView?

Question

Android

I can not put the cells of the parsed page in the ListView.

import android.app.Activity;
import android.content.Context;
import android.os.AsyncTask;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import org.jsoup.Connection;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.Map;

import static android.R.layout.simple_list_item_1;

public class MyActivity extends Activity {
    /**
     * Called when the activity is first created.
     */
    private Context mContext;
    private TextView myTextView;
    class MyTask extends AsyncTask<Void, Void, Void> {

        String title;

        @Override
        protected Void doInBackground(Void... params) {
            ListView listView = (ListView) findViewById(R.id.listView);

            // Создаём пустой массив для хранения имен котов
            final ArrayList<String> catnames = new ArrayList<String>();

            // Создаём адаптер ArrayAdapter, чтобы привязать массив к ListView
            final ArrayAdapter<String> adapter;
            adapter = new ArrayAdapter<String>(mContext,android.R.layout.simple_list_item_1, catnames);

            // Привяжем массив через адаптер к ListView
            listView.setAdapter(adapter);
            try {
                Connection.Response res= Jsoup
                        .connect("https://site.ru")
                        .method(Connection.Method.GET)
                        .execute();


                res= Jsoup
                        .connect("https://www.site.ru/login/")
                        .data("login","123")
                        .cookies(res.cookies())
                        .data("password","321")
                        .method(Connection.Method.POST)
                        .execute();


                Elements ele = doc.select("font[face=arial]");
                title = ele.text();


                String text;
                for( Element element : doc.select("td#ele_id") ) 
                {
                    text = element.text(); // Get the Text of the Link

                    catnames.add(0,text);
                    adapter.notifyDataSetChanged();
                }
               // Iterator<Element> iterator = ele.listIterator();


               // Element element = iterator.next();



            } catch (IOException e) {
                // e.printStackTrace();
                myTextView.setText("error");
            }


            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            super.onPostExecute(result);

            myTextView.setText(title);
        }
    }
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        mContext = this;
        myTextView = (TextView) findViewById(R.id.textView);

        MyTask mt = new MyTask();
        mt.execute();

    }
}

I understand listView.setAdapter(adapter); you need to put it in onCreate, but you can't put jsoup there.

Answer 1

You cannot communicate with UI elements not from MainThread. You do this in doInBackground(). Give catnames as the result of doInBackground, and loop through the array into the adapter once in onPostExecute. This is at least.
In general, asynctasks for network interaction are not good to use. There are normal libraries for this, for example - Retrofit.