Getting error while clicking on the button on which I am calling Async task?

Question

Here is my code in which on clicking I am calling AttemptLogin method.

class NewActivity extends AppCompatActivity implements View.OnClickListener {


EditText editEmail, editPassword, editName;
Button btnSignIn, btnRegister;
private ProgressDialog pDialog;

String URL= "https://xyz/restapi/registration";

JSONParser jsonParser=new JSONParser();

int i=0;

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




    btnRegister=(Button)findViewById(R.id.btnRegister);
    btnRegister.setOnClickListener(this);

    /*btnSignIn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            AttemptLogin attemptLogin= new AttemptLogin();
            attemptLogin.execute(editName.getText().toString(),editPassword.getText().toString(),"");
        }
    });*/

    /*btnRegister.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            new AttemptLogin().execute();
            }


    });*/
}

@Override
public void onClick(View v) {
    new AttemptLogin().execute();
}

private class AttemptLogin extends AsyncTask<String, String, JSONObject> {

    @Override

    protected void onPreExecute() {

        super.onPreExecute();
        pDialog = new ProgressDialog(NewActivity.this);
        pDialog.setMessage("Attempting for registering...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();

    }

    @Override

    protected JSONObject doInBackground(String... args) {





        ArrayList params = new ArrayList();
        params.add(new BasicNameValuePair("cust_firstname", "Sai"));
        params.add(new BasicNameValuePair("cust_lastname", "Kumar"));
        params.add(new BasicNameValuePair("cust_phoneno", "9989219692"));
        params.add(new BasicNameValuePair("cust_confirmpass", "Sai@123"));
        params.add(new BasicNameValuePair("cust_pass", "Sai@123"));
            params.add(new BasicNameValuePair("cust_username", "sai@gmail.com"));

        JSONObject json = jsonParser.makeHttpRequest(URL, "POST", params);


        return json;

    }

    protected void onPostExecute(JSONObject result) {

        // dismiss the dialog once product deleted
        //Toast.makeText(getApplicationContext(),result,Toast.LENGTH_LONG).show();

        try {
            if (result != null) {
                Toast.makeText(getApplicationContext(),result.getString("message"),Toast.LENGTH_LONG).show();
            } else {
                Toast.makeText(getApplicationContext(), "Unable to retrieve any data from server", Toast.LENGTH_LONG).show();
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }


    }

}

}

on button click i want to post data directly but getting error as

Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference

If there are any nice tutorials for registering details for Async task means please let me know.

Have you initialized your buttons properly? You are getting NPE, since you haven't casted `btnSignIn` which might be in your XML resource. — Rohit Sharma, May 28 '18 at 12:15
Thanks guys i had kept wrong xml file in my code thats why got error sorry for troubling. can you please help me out in posting the details. I am getting error as Error parsing data org.json.JSONException: Value — lakshman kumar, May 28 '18 at 12:29

score 0 · Answer 1 · edited May 28 '18 at 12:10

0

@Override
public void onClick(View v) {
    switch(v.getId){
    case R.id.button:
   new AttemptLogin().execute();
 }
}

try this one

edited May 28 '18 at 12:10

Naveen T P

6,955
2
22
29

answered May 28 '18 at 12:04

Mohsin mithawala

66
5

getting same error even after using switch case that you given – lakshman kumar May 28 '18 at 12:12
is your api perfectly working in postman? did u check that? – Mohsin mithawala May 28 '18 at 12:13
Api is working fine i had kept other xml file in the code so thats the error sorry for the trouble. can you please help me out in posting the details. I am getting error as Error parsing data org.json.JSONException: Value – lakshman kumar May 28 '18 at 12:27

score 0 · Answer 2 · answered May 28 '18 at 12:37

The id of the button is correct? It corresponds with the id in XML layout?

Use in onCreate:

 btnRegister.setOnClickListener(btnLoginClick);

Then, out of the onCreate declare method:

private View.OnClickListener btnLoginClick = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
          ...
          //write your code
        }
    };

score 0 · Answer 3 · answered May 28 '18 at 15:24

Try this out.

@Override
public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btnRegister: 
              new AttemptLogin().execute();
              break;
            default:
              break;
    }
 }

The official Android Developer site should be your closed friend. Make sure you read this: https://developer.android.com/reference/android/os/AsyncTask

Getting error while clicking on the button on which I am calling Async task?

3 Answers3