Asynktask does not run doInBackGround

Question

I am developing an android app for the integrative college project in which I need to pass parameter 2 strings (user and password) to a PHP API that will return a User object or a Boolean false.

I am using Asynctask for this. But at the time I run the debug, it does not run doInBackground.

activity_main.xml

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

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal"
            android:background="@android:color/holo_green_light">

            <TextView
                android:id="@+id/textView"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="UniLibrary"
                android:textAlignment="center"
                android:textColor="#dddddd"
                android:textSize="25dp"
                android:textStyle="bold"/>

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical"
            android:padding="5dp">

            <TextView
                android:id="@+id/txtLogin"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Usuário"
                android:textAppearance="?android:attr/textAppearanceMedium" />

            <EditText
                android:id="@+id/edtUsuario"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:ems="10" >
            </EditText>


            <TextView
                android:id="@+id/txtSenha"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Senha"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:inputType="number"/>

            <EditText
                android:id="@+id/edtSenha"
                android:layout_width="match_parent"
                android:layout_height = "wrap_content"
                android:ems="10"
                android:inputType="textPassword" />

            <Button
                android:id="@+id/btnEntrar"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Entrar"
                android:onClick="click"/>

        </LinearLayout>

    </LinearLayout>
</android.support.constraint.ConstraintLayout>

Mainactivity

package unifacear.edu.br.unilibrary_mobile;

import android.content.Context;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import unifacear.edu.br.unilibrary_mobile.Model.Entity.Login;
import unifacear.edu.br.unilibrary_mobile.Model.Entity.Permissao;
import unifacear.edu.br.unilibrary_mobile.Model.Service.LoginService;

public class MainActivity extends AppCompatActivity {

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

    }



    public void login(Boolean aceite) {
        if(aceite) {
            Intent intent = new Intent(this, ListActivityLivro.class);

            startActivity(intent);
        } else {
            Toast.makeText(this, "Usuario ou senha incorretos", Toast.LENGTH_LONG).show();
        }
    }

    public void click(View v) {
        Button btnEntrar = (Button) v;

        EditText usuario = findViewById(R.id.edtUsuario);
        EditText senha = findViewById(R.id.edtSenha);
        Login l = new Login();
        l.setUsuario(usuario.getText().toString());
        l.setSenha(senha.getText().toString());

        LoginService s = new LoginService(getApplicationContext());
        s.setActivity(this);
        s.execute(l);
    }
}

Loginservice

package unifacear.edu.br.unilibrary_mobile.Model.Service;

import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;
import android.widget.Toast;

import org.json.JSONArray;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import unifacear.edu.br.unilibrary_mobile.ExibeLivroActivity;
import unifacear.edu.br.unilibrary_mobile.MainActivity;
import unifacear.edu.br.unilibrary_mobile.Model.Entity.Livro;
import unifacear.edu.br.unilibrary_mobile.Model.Entity.Login;
import unifacear.edu.br.unilibrary_mobile.Model.Entity.Usuario;

public class LoginService extends AsyncTask<Login,String,String> {
    private String urlString = "https://unilibrary.000webhostapp.com/usuario/login";


    private MainActivity activity;
    private ProgressDialog dialog;
    private Context context;

    public LoginService(Context context) {
        this.context = context;
    }

    public void setActivity(MainActivity activity) {
        this.activity = activity;
    }



    @Override
    protected void onPreExecute() {
        dialog = new ProgressDialog(context);
        dialog.setTitle("Por favor aguarde");
        dialog.setMessage("Carregando...");
        dialog.show();
    }

    @Override
    protected String doInBackground(Login... logins) {
        JSONObject json = new JSONObject();

        try{

            json.put("usuario", logins[0].getUsuario());
            json.put("senha", logins[0].getSenha());

            URL url = new URL(urlString);

            HttpURLConnection connection = (HttpURLConnection)url.openConnection();

            connection.setRequestMethod("POST");
            connection.setRequestProperty("Content-type", "application/json");
            connection.setDoOutput(true);
            connection.setDoInput(true);


            PrintStream printStream = new PrintStream(connection.getOutputStream());
            printStream.println(json.toString());

            connection.connect();

            connection.getOutputStream();

            BufferedReader br = new BufferedReader(
                    new InputStreamReader(url.openStream()));

            StringBuilder sb = new StringBuilder();

            String result;

            while((result = br.readLine()) != null){
                sb.append(result + "\n");
            }

            br.close();
            return sb.toString();
        } catch(Exception e){
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(String result) {

        if(!result.equalsIgnoreCase("false")) {

            try {
                JSONArray jsonArray = new JSONArray(result);
                List<Usuario> usuarios = new ArrayList<>();

                for (int i = 0; i < jsonArray.length(); i++) {
                    JSONObject object = jsonArray.getJSONObject(i);

                    Usuario usuario = new Usuario();
                    usuario.setId(object.getInt("id"));
                    usuario.setUsuario(object.getInt("usuario"));
                    usuario.setPermissao(object.getInt("permissao"));
                    usuario.setStatus(object.getBoolean("status"));

                    usuarios.add(usuario);

                    dialog.dismiss();
                }
                activity.login(true);
            } catch (Exception e) {
                e.printStackTrace();
            }

        } else {
            activity.login(false);
            dialog.dismiss();
        }
    }
}

If anyone can help this young padawan, I will be eternally grateful.

Answer 1

Hello, from what I understand you are wanting to debug inside theInBackground, so first add in theInBackground right at the beginning:

if(android.os.Debug.isDebuggerConnected())
    android.os.Debug.waitForDebugger();

If debug still doesn’t work you can try using Log.d within theInBackground, at least with the logcat you can check where your logic is going.