Android: How to Convert a String to JSON and get the data?

Question

Though there are many resources and links given, all of them seem to be not working for me. I have a php code which returns a JSON. I want to extract values from it in my Android application.Here goes the php code.

<?php
if($_SERVER['REQUEST_METHOD']=='POST'){

        $username1 = $_POST['username'];
        $password1= $_POST['password'];

        require_once'config.php';
        $sql = "SELECT * FROM users";
        $result1 = $conn->query($sql);
        $stat= 1;
        if ($result1->num_rows > 0) {
            // output data of each row
            while($row1 = $result1->fetch_assoc()) {
                $user=$row1['username'];
                $pass=$row1['password'];
                if($user == $username1 && $pass == $password1){
                    $arr = array("stat" => "Valid","resp"=>"Logged in");
                    echo json_encode($arr);
                    $stat = 0;
                    break;
                }
            }
        }
        if ($stat == 1) {
            echo "Username or Password is wrong!";
         } 
}
else{
echo 'Error in method';
}

?>

And this is my MainActivity.java

public class MainActivity extends AppCompatActivity implements View.OnClickListener {



    private static final String REGISTER_URL = "http://10.22.20.129/alak/login.php";

    public static final String KEY_USERNAME = "username";
    public static final String KEY_PASSWORD = "password";



    private EditText editTextUsername;

    private EditText editTextPassword;

    private Button buttonRegister;

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

        editTextUsername = (EditText) findViewById(R.id.TFusername);
        editTextPassword = (EditText) findViewById(R.id.TFpassword);


        buttonRegister = (Button) findViewById(R.id.Blogin);

        buttonRegister.setOnClickListener(this);
    }

    private void registerUser(){
        final String username = editTextUsername.getText().toString().trim();
        final String password = editTextPassword.getText().toString().trim();

        StringRequest stringRequest = new StringRequest(Request.Method.POST, REGISTER_URL,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {

                        Toast.makeText(MainActivity.this,response.toString(), Toast.LENGTH_LONG).show();
                        try {
                            JSONArray json = new JSONArray(response.toString());
                            String x=(String) json.getString("resp");
                            if (x == "Logging") {
                                Intent in=new Intent(MainActivity.this,SignUp.class);
                                startActivity(in);
                            }

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Toast.makeText(MainActivity.this,error.toString(),Toast.LENGTH_LONG).show();
                    }
                }){
            @Override
            protected Map<String,String> getParams(){
                Map<String,String> params = new HashMap<String, String>();
                params.put("username",username);
                params.put("password",password);
                return params;
            }

        };

        RequestQueue requestQueue = Volley.newRequestQueue(this);
        requestQueue.add(stringRequest);
    }

    @Override
    public void onClick(View v) {
        if(v == buttonRegister){
            registerUser();
        }
    }
}

Possible duplicate of [How to parse JSON in Java](http://stackoverflow.com/questions/2591098/how-to-parse-json-in-java) — Rohit Arya, Apr 17 '16 at 18:07
what exactly does not work? Debug your logcat and show the response or possible error — Kostas Drak, Apr 17 '16 at 18:09
I get my response like {"stat" : "Valid","resp" :"Logged in"}. Now i want the value of stat(i.e Valid). — Devunuri Saipraneeth, Apr 17 '16 at 18:17

score 0 · Answer 1 · answered Apr 17 '16 at 18:26

I used this and found the solution.Thanks

JSONObject obj = null;
                        try {
                            obj = new JSONObject(response.toString());
                            String stat = obj.getString("stat");
                            Toast.makeText(MainActivity.this,stat.toString(), Toast.LENGTH_LONG).show();
                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

please update your question instead of posting it as an answer — Sarah Maher, Apr 17 '16 at 18:30

score 0 · Answer 2 · answered Apr 17 '16 at 18:28

0

the easiest way for me was using Gson for desirlization https://www.javacodegeeks.com/2011/01/android-json-parsing-gson-tutorial.html

answered Apr 17 '16 at 18:28

Sarah Maher

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Android: How to Convert a String to JSON and get the data?

2 Answers2