Toast displays a value but textview throws Null pointer error

Question

I am using this code to post data to php -

   package com.nas.cruzer;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import com.nas.cruzer.UserEditProfileActivity.UpdateInfo;
import com.nas.cruzer.util.JSONParser;
import com.nas.cruzer.util.UserInfo;
import com.nas.cruzer.util.Util;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.os.StrictMode;
import android.util.Log;
import android.view.MenuItem;
import android.webkit.JavascriptInterface;
import android.webkit.WebView;
import android.widget.TextView;
import android.widget.Toast;

@SuppressLint("SetJavaScriptEnabled") public class payment extends Activity {

     private static final String TAG = "payment.java";
    private WebView webView;
    JSONParser jparser=new JSONParser();
    public static HashMap<String, String> pay;
    public static final String payUrl = "http://fuelongo.com/ap2/fog/pay/PayUMoney_form.php";
    String x,y,tot,fuel,mail,phone,responseServer;
    TextView test;
    Context con= payment.this;

    @SuppressLint("JavascriptInterface") public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        new PostDataAsyncTask().execute();
        setContentView(R.layout.payment);
       webView = (WebView) findViewById(R.id.pay);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.addJavascriptInterface(new WebAppInterface(this), "Android"); 


        webView.loadUrl(payUrl);

        //test=(TextView) findViewById(R.id.x);
    }


    public class PostDataAsyncTask extends AsyncTask<String, String, String> {

        protected void onPreExecute() {
            super.onPreExecute();
            // do stuff before posting data
        }

        @Override
        protected String doInBackground(String... strings) {
            try {

                    postText();


                // post a file


            } catch (NullPointerException e) {
                e.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(String lenghtOfFile) {
            // do stuff after posting data
        }
    }

    // this will post our text data
    private void postText(){
        try{
            // url where the data will be posted

            Log.v(TAG, "postURL: " + payUrl);

            // HttpClient
            HttpClient httpClient = new DefaultHttpClient();

            // post header
            HttpPost httpPost = new HttpPost(payUrl);

            // add your data
            List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
            nameValuePairs.add(new BasicNameValuePair("firstname", "Mike"));
            nameValuePairs.add(new BasicNameValuePair("lastname", "Dalisay"));
            nameValuePairs.add(new BasicNameValuePair("email", "mike@testmail.com"));

            httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

            // execute HTTP post request
            HttpResponse response = httpClient.execute(httpPost);
            HttpEntity resEntity = response.getEntity();

            if (resEntity != null) {

                String responseStr = EntityUtils.toString(resEntity).trim();
                Log.v(TAG, "Response: " +  responseStr);

                // you can add an if statement here and do other actions based on the response
            }

        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }






    public class WebAppInterface {
        Context mContext;

        /** Instantiate the interface and set the context */
        WebAppInterface(Context c) {
            mContext = c;





        }







        /** Show a toast from the web page */

         }
        }

The above code after performing a query in my php gets the desired value and is being toast , but when I am trying to set text to a text view it shows Null Pointer exception.

Any help?

This is my log cat out put,"s" is the value i am posting and kitkat is the value queried from database

   06-10 15:37:56.390: V/payment.java(28930): Response: Array
06-10 15:37:56.390: V/payment.java(28930): (
06-10 15:37:56.390: V/payment.java(28930):     [firstname] => Mike
06-10 15:37:56.390: V/payment.java(28930):     [lastname] => Dalisay
06-10 15:37:56.390: V/payment.java(28930):     [email] => mike@testmail.com
06-10 15:37:56.390: V/payment.java(28930): )
06-10 15:37:56.390: V/payment.java(28930): mike@testmail.com<html>
06-10 15:37:56.390: V/payment.java(28930):   <head>
06-10 15:37:56.390: V/payment.java(28930):   <script>
06-10 15:37:56.390: V/payment.java(28930):     var hash = '';
06-10 15:37:56.390: V/payment.java(28930):     function submitPayuForm() {
06-10 15:37:56.390: V/payment.java(28930):       if(hash == '') {
06-10 15:37:56.390: V/payment.java(28930):         return;
06-10 15:37:56.390: V/payment.java(28930):       }
06-10 15:37:56.390: V/payment.java(28930):       var payuForm = document.forms.payuForm;
06-10 15:37:56.390: V/payment.java(28930):       payuForm.submit();
06-10 15:37:56.390: V/payment.java(28930):     }
06-10 15:37:56.390: V/payment.java(28930):   </script>
06-10 15:37:56.390: V/payment.java(28930):   </head>
06-10 15:37:56.390: V/payment.java(28930):   <body onload="submitPayuForm()">
06-10 15:37:56.390: V/payment.java(28930):     <h2>PayU Form</h2>
06-10 15:37:56.390: V/payment.java(28930):     <br/>
06-10 15:37:56.390: V/payment.java(28930):      
06-10 15:37:56.390: V/payment.java(28930):       <span style="color:red">Please fill all mandatory fields.</span>
06-10 15:37:56.390: V/payment.java(28930):       <br/>
06-10 15:37:56.390: V/payment.java(28930):       <br/>
06-10 15:37:56.390: V/payment.java(28930):         <form action="" method="post" name="payuForm">
06-10 15:37:56.390: V/payment.java(28930):       <input type="hidden" name="key" value="JBZaLc" />
06-10 15:37:56.390: V/payment.java(28930):       <input type="hidden" name="hash" value=""/>
06-10 15:37:56.390: V/payment.java(28930):       <input type="hidden" name="txnid" value="61937a215af325da6a54" />
06-10 15:37:56.390: V/payment.java(28930):       <table>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td><b>Mandatory Parameters</b></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Amount: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="amount" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>First Name: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="firstname" id="firstname" value="Mike" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Email: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="email" id="email" value="mike@testmail.com" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Phone: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="phone" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Product Info: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><textarea name="productinfo"></textarea></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Success URI: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><input name="surl" value="" size="64" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Failure URI: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><input name="furl" value="" size="64" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><input type="hidden" name="service_provider" value="payu_paisa" size="64" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td><b>Optional Parameters</b></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Last Name: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="lastname" id="lastname" value="Dalisay" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Cancel URI: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="curl" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Address1: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="address1" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Address2: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="address2" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>City: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="city" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>State: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="state" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Country: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="country" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Zipcode: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="zipcode" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF1: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf1" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF2: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf2" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF3: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf3" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF4: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf4" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF5: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf5" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>PG: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="pg" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):                       <td colspan="4"><input type="submit" value="Submit" /></td>
06-10 15:37:56.390: V/payment.java(28930):                   </tr>
06-10 15:37:56.390: V/payment.java(28930):       </table>
06-10 15:37:56.390: V/payment.java(28930):     </form>
06-10 15:37:56.390: V/payment.java(28930):   </body>
06-10 15:37:56.390: V/payment.java(28930): </html>

Possible duplicate of [What is a NullPointerException, and how do I fix it?](http://stackoverflow.com/questions/218384/what-is-a-nullpointerexception-and-how-do-i-fix-it) — Mike M., Jun 10 '16 at 04:36
I guess the value is ok but the TextView is not inflated so you get a Null Pointer Exception on setText — Alexandre Martin, Jun 10 '16 at 04:37
Do something like TextView test = (TextView) findViewById(R.id.tvTest); — Alexandre Martin, Jun 10 '16 at 04:39
@AlexandreMartin- can you help me out with the solution please coz of just this my project got stuck from 20 days — Murthy Varanasi, Jun 10 '16 at 04:39
TextView test;test=(TextView) findViewById(R.id.x); i did it this way — Murthy Varanasi, Jun 10 '16 at 04:41
@MurthyVaranasi: please post your activity and its xml code where you have the Textview — Manish Jain, Jun 10 '16 at 04:52
@ManishJain This is the xml,and activity is what i posted in the question — Murthy Varanasi, Jun 10 '16 at 05:00
did you instantiate your text view by findviewbyid in java file? — Rohan Pawar, Jun 10 '16 at 05:51
it would be great if you post whole code, might be sequence code is wrong, your code executes before variable init or something — Rohan Pawar, Jun 10 '16 at 09:33

score 0 · Answer 1 · answered Jun 10 '16 at 05:34

0

Use AsynTask Class or Intent service to handle UI changes.

answered Jun 10 '16 at 05:34

MinnuKaAnae

1,646
3
23
35

score 0 · Answer 2 · answered Jun 10 '16 at 05:41

Null Pointer Exception here is not thrown because of the reverseString here. It is because test is null.

This can be because of any of the below reasons. 1. Make sure your below piece of code is run before calling test.setText test=(TextView) findViewById(R.id.x)

Make sure view 'x' exists in the layout you are inflating.

Also make sure you are updating the textview on main thread.

Rohan Pawar · Answer 3 · 2016-06-10T11:25:43.147

First thing is un-comment test=(TextView) findViewById(R.id.x); and second thing is your calling new PostDataAsyncTask().execute() before initialize textview, so initialize all variables first then do rest of your code load,execute etc.

Your onCreate() code should be like this

    super.onCreate(savedInstanceState);
    setContentView(R.layout.payment);
    test=(TextView) findViewById(R.id.x);
    webView = (WebView) findViewById(R.id.pay);
    webView.getSettings().setJavaScriptEnabled(true);
    webView.addJavascriptInterface(new WebAppInterface(this), "Android");
    webView.loadUrl(payUrl);
    new PostDataAsyncTask().execute();

and then test.setText("whatever you want"); and also check that id.x is available in payment layout

score 0 · Answer 4 · answered Jun 10 '16 at 13:12

Atlast the issue resolved with the following code:

 public void postData() throws IOException, ClientProtocolException {  

        List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();  
        nameValuePairs.add(new BasicNameValuePair("name", x));  
        nameValuePairs.add(new BasicNameValuePair("mail", y));
        nameValuePairs.add(new BasicNameValuePair("phone", phone));
        nameValuePairs.add(new BasicNameValuePair("fuel", fuel));
        nameValuePairs.add(new BasicNameValuePair("total", tot));

        HttpClient httpclient = new DefaultHttpClient();  
        HttpPost httppost = new HttpPost(payUrl);  
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));  

        HttpResponse response = httpclient.execute(httppost);  
        String data = new BasicResponseHandler().handleResponse(response);
       Log.e("data",data);

        webView.loadData(data, "text/html", "utf-8");
   }

But the button in the webview is not functioning And can someone explain me what this code does.

Replacing this webView.loadData(data, "text/html", "utf-8"); with webView.loadDataWithBaseURL(payUrl, data, "text/html", "utf-8", "www.html.com"); made the button also functional.Thanks for the support — Murthy Varanasi, Jun 10 '16 at 13:40

Toast displays a value but textview throws Null pointer error

4 Answers4