Develop Reference

JSON PARSING error while running app

Iam making an app with connecting to server and reading the json,but am getting java.lang.String org.json.JSONObject.toString()' on a null object reference error.please help me.thanks in advance
Here is my activity
public class NewProductActivity extends Activity {
private ProgressDialog pDialog;
JSONParser jsonParser = new JSONParser();
EditText inputName;
Button createBtn;
private static String url_create_product = "http://10.0.2.2/create_product.php";
private static final String TAG_SUCCESS = "success";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add_product);
inputName = (EditText)findViewById(R.id.nameEt);
createBtn = (Button)findViewById(R.id.createBt);
createBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
new CreateNewProduct().execute();
}
});
}
class CreateNewProduct extends AsyncTask<String,String,String>{
String name = inputName.getText().toString();
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(NewProductActivity.this);
pDialog.setMessage("Creating Product..");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args){
inputName = (EditText)findViewById(R.id.nameEt);
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("name",name ));
JSONObject json = jsonParser.makeHttprequest(url_create_product,
"POST", params);
// check log cat fro response
Log.d("Create Response", json.toString());
// check for success tag
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// successfully created product
Intent i = new Intent(getApplicationContext(), AllProductsActivty.class);
startActivity(i);
// closing this screen
finish();
} else {
// failed to create product
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String file_url) {
// dismiss the dialog once done
pDialog.dismiss();
}
}
}
here is my Json parser
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
public JSONParser(){}
public JSONObject makeHttprequest(String url, String method, List<NameValuePair> params){
try {
if (method.equals( "POST")){
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if (method .equals( "GET")){
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params,"url");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
}catch (UnsupportedEncodingException e ){
e.printStackTrace();
}catch (ClientProtocolException e){
e.printStackTrace();
}catch (IOException e){
e.printStackTrace();
}
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null){
sb.append(line + "\n");
}
is.close();
json = sb.toString();
}catch (Exception e){
Log.e("Buffer error","Error Converting");
}
try {
jObj = new JSONObject(json);
}catch (JSONException e){
Log.e("JSON Parser","Error parsing");
}
return jObj;
}
}
here is my php file
<?php
$response = array();
if(isset($_POST['name'])){
$name = $_POST['name'];
$con = mysql_connect("localhost","root","root");
$db = mysql_select_db("db");
$result = mysql_query("INSERT INTO product(name) VALUES ('$name')");
if($result){
$response["success"] = 1;
$response["message"] = "successfully inserted";
echo json_encode($respone);
}
else {
$response["success"] = 0;
$response["message"] ="error occured";
echo json_encode($response);
}
} else{
$response["success"] = 0;
$response["message"] = "required feild missing";
echo json_encode($response);
}
?>
here is my error log
06-27 18:35:55.097 3462-4317/com.example.joel339.sample E/JSON Parser: Error parsing
--------- beginning of crash
06-27 18:35:55.097 3462-4317/com.example.joel339.sample E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1
Process: com.example.joel339.sample, PID: 3462
java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:309)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.toString()' on a null object reference
at com.example.joel339.sample.NewProductActivity$CreateNewProduct$override.doInBackground(NewProductActivity.java:70)
at com.example.joel339.sample.NewProductActivity$CreateNewProduct$override.access$dispatch(NewProductActivity.java)
at com.example.joel339.sample.NewProductActivity$CreateNewProduct.doInBackground(NewProductActivity.java:0)
at com.example.joel339.sample.NewProductActivity$CreateNewProduct.doInBackground(NewProductActivity.java:50)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588) 
at java.lang.Thread.run(Thread.java:818) 
i am able to create a new product,my product list json is being updated,but i cant see the products list
here is the products list activity
public class AllProductsActivty extends ListActivity {
private ProgressDialog pDialog;
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String,String>> productsList;
private static String url_all_products = "http://10.0.2.2/get_all_products_details.php";
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCTS = "product";
private static final String TAG_PID = "pid";
private static final String TAG_NAME = "name";
JSONArray products = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_products);
productsList = new ArrayList<HashMap<String, String>>();
ListView lv = getListView();
new LoadAllProducts().execute(url_all_products);
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
String pid = ((TextView)view.findViewById(R.id.pid)).getText().toString();
Intent in = new Intent(getApplicationContext(),EditProductActivity.class);
in.putExtra(TAG_PID,pid);
startActivityForResult(in,100);
}
});
}
#Override
protected void onActivityResult(int requestCode,int resultCode , Intent data){
super.onActivityResult(requestCode,resultCode,data);
if(resultCode == 100){
Intent intent = getIntent();
finish();
startActivity(intent);
}
}
class LoadAllProducts extends AsyncTask< String,String,String>{
#Override
protected void onPreExecute(){
super.onPreExecute();
pDialog = new ProgressDialog(AllProductsActivty.this);
pDialog.setMessage("LoadingProducts.Please Wait");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args){
List<NameValuePair> params = new ArrayList<NameValuePair>();
JSONObject json = jParser.makeHttprequest(url_all_products,"GET",params);
Log.d("Allproducts:",json.toString());
try{
int success = json.getInt(TAG_SUCCESS);
if (success == 1){
products = json.getJSONArray(TAG_PRODUCTS);
for (int i = 0;i < products.length();i++){
JSONObject c =products.getJSONObject(i);
String id = c.getString(TAG_PID);
String name = c.getString(TAG_NAME);
HashMap<String,String> map = new HashMap<String, String>();
map.put(TAG_PID,id);
map.put(TAG_NAME,name);
productsList.add(map);
}
}else{
Intent i = new Intent(getApplicationContext(),NewProductActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(i);
}
}
catch (JSONException e){
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String file_url){
pDialog.dismiss();
runOnUiThread(new Runnable() {
#Override
public void run() {
ListAdapter adapter = new SimpleAdapter(
AllProductsActivty.this,productsList,R.layout.list_view,new String[]{TAG_PID,TAG_NAME},
new int[]{R.id.pid,R.id.name});
setListAdapter(adapter);
}
});
}
}
}

The error is in this line.
Log.d("Create Response", json.toString());
Because of null object, it gives you null pointer exception.
Double check with this line, Just add the safety check as below
if (json == null || json == JSONObject.NULL){
// error handling..
}
else
{
// Your code
}
Suggestion:(not related to crash)
Just remove this line inputName = (EditText)findViewById(R.id.nameEt); in doInBackground(). You already initilised this variable in onCreate(), so just remove it.

Android Json unicode parsin

my sql server collation is utf8 unicode
my php works fine
my android project is working fine with normal characters but in case of arabic char it display error "Error parsing json" line 233 in the activity listed below
I've tried my sql and php on other project its works but here I dont know whats the error json must be utf8 by defult
public class DealsListActivity extends Activity {
private String id;
// Progress Dialog
private ProgressDialog pDialog;
// creating JSON Parser object
JSONParser jParser = new JSONParser();
private static String url = "http://xxxxxxxxxxxx.get_all_deals_by_id.php";
// JSON Node names
private static final String TAG_DEALS = "deals";
private static final String TAG_ID = "id";
private static final String TAG_DEALNAME = "dealName";
private static final String TAG_PRICE = "price";
private static final String TAG_DESCRIPTION = "description";
private static final String TAG_RESTID = "restID";
private static final String TAG_RESTNAME = "restName";
private static final String TAG_RESTTYPE = "restType";
private static final String TAG_LAT = "restLat";
private static final String TAG_LNG = "restLng";
private static final String TAG_SUCCESS = "success";
private JSONObject json;
JSONArray restaurantDealsData = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> restaurantDealsList = new ArrayList<HashMap<String, String>>();
ListView myList;
private String[] dealID;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_deals_list);
id = getIntent().getStringExtra("id");
myList = (ListView) findViewById(R.id. restDealListView);
new LoadDeals().execute();
}
/**
* Background Async Task to Load all deals by making
* HTTP Request
* */
class LoadDeals extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(DealsListActivity.this);
pDialog.setMessage("Loading Restaurant Deals. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
#Override
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
Log.v("id", id);
params.add(new BasicNameValuePair("id", id));
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url, "GET", params);
// check log cat for JSON string from URL
Log.v("restaurantDealsJSON: ", json.toString());
// return json as string to using in the user interface
return json.toString();
}
#Override
protected void onPostExecute(final String jsonStr) {
// dismiss the dialog after getting all products
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
#Override
public void run() {
/**
* Updating parsed JSON data into listview
* */
try {
json = new JSONObject(jsonStr);
} catch (JSONException e1) {
// print error message to log
e1.printStackTrace();
error("There are no Deals");
}
try {
// Checking for SUCCES TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// restaurant found
// Getting Array of restaurant
restaurantDealsData = json.getJSONArray(TAG_DEALS);
displayDeals(restaurantDealsData.toString());
} else {
error("There is no Deals available!");
}
} catch (JSONException e) {
error("There has been an error please try again!");
e.printStackTrace();
}
}
});
}
}
public void error(String error) {
// Log.v("ERROR", "2");
AlertDialog.Builder builder = new AlertDialog.Builder(
DealsListActivity.this);
// Log.v("ERROR", "3");
builder.setTitle("Error");
builder.setMessage(error);
builder.setCancelable(false);
builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int id) {
// Log.v("TEST", "1");
Intent i = new Intent(getApplicationContext(),
TabsViewPagerFragmentActivity.class);
startActivity(i);
overridePendingTransition(R.anim.fade_in, R.anim.fade_out);
finish();
}
});
AlertDialog alert = builder.create();
alert.show();
}
public void displayDeals(String result) {
JSONArray restaurantDealsData = null;
try {
restaurantDealsList.clear();
restaurantDealsData = new JSONArray(result);
dealID = new String[restaurantDealsData.length()];
// looping through all technical data
for (int i = 0; i < restaurantDealsData.length(); i++) {
JSONObject td = restaurantDealsData.getJSONObject(i);
// Storing each json item in variable
String id = td.getString(TAG_ID);
dealID[i] = id;
String name = td.getString(TAG_DEALNAME);
String price = td.getString(TAG_PRICE);
String description = td.getString(TAG_DESCRIPTION);
String restaurantID = td.getString(TAG_RESTID);
String restaurantName = td.getString(TAG_RESTNAME);
String restaurantType = td.getString(TAG_RESTTYPE);
String lat = td.getString(TAG_LAT);
String lng = td.getString(TAG_LNG);
Log.v("lat", lat);
Log.v("lng", lng);
// Creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_ID, id);
map.put(TAG_DEALNAME, name);
map.put(TAG_PRICE, price);
map.put(TAG_DESCRIPTION, description);
map.put(TAG_RESTID, restaurantID);
map.put(TAG_RESTNAME, restaurantName);
map.put(TAG_RESTTYPE, restaurantType);
map.put(TAG_LAT, lat);
map.put(TAG_LNG, lng);
// adding HashMap to ArrayList
restaurantDealsList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
error("Error parsing json");
}
// add to list view
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(getApplicationContext(),
restaurantDealsList, R.layout.deals_list_item, new String[] {
TAG_DEALNAME, TAG_RESTNAME, TAG_RESTTYPE }, new int[] {
R.id.dealName, R.id.restaurantName, R.id.type });
// updating listview
myList.setAdapter(adapter);
//handling user click list item
myList.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
//start the next activity - Restaurant Details
Intent i = new Intent(getApplicationContext(), DealDetails.class);
i.putExtra("ID", dealID[arg2]);
startActivity(i);
overridePendingTransition(R.anim.slide_in_right, R.anim.slide_out_left);
}
});
}
}
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET mehtod
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}

You should read the input stream using the charset UTF-8 like this:
replace
BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
by
BufferedReader reader = new BufferedReader(new InputStreamReader(is, "UTF-8));
I use this to decode json with japanese inside.

Show data from world weather online api

I am developing weather application by using world weather online API
for android.How i show data in application? data is showing in logcat.Following is my code.
MainActivity.java
public class MainActivity extends ListActivity {
private ProgressDialog pDialog;
// URL to get contacts JSON
private static String url = "http://api.worldweatheronline.com/free/v1/weather.ashx?q=";
// JSON Node names
private static final String TAG_DATA = "data";
private static final String TAG_NAME = "name";
// contacts JSONArray
JSONArray data = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> dataList;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
dataList = new ArrayList<HashMap<String, String>>();
ListView lv = getListView();
new GetContacts().execute();
}
/**
* Async task class to get json by making HTTP call
* */
private class GetContacts extends AsyncTask<Void, Void, Void> {
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
#Override
protected Void doInBackground(Void... arg0) {
// Creating service handler class instance
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
data = jsonObj.getJSONArray(TAG_DATA);
// looping through All Contacts
for (int i = 0; i < data.length(); i++) {
JSONObject c = data.getJSONObject(i);
// tmp hashmap for single contact
HashMap<String, String> contact = new HashMap<String, String>();
// adding each child node to HashMap key => value
// adding contact to contact list
dataList.add(contact);
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(MainActivity.this,
dataList, R.layout.list_item, new String[] { TAG_NAME }, new int[] {
R.id.name });
setListAdapter(adapter);
}
}
}
ServiceHandler.java
public class ServiceHandler {
static String response = null;
public final static int GET = 1;
public final static int POST = 2;
public ServiceHandler() {
}
/**
* Making service call
* #url - url to make request
* #method - http request method
* */
public String makeServiceCall(String url, int method) {
return this.makeServiceCall(url, method, null);
}
/**
* Making service call
* #url - url to make request
* #method - http request method
* #params - http request params
* */
public String makeServiceCall(String url, int method,
List<NameValuePair> params) {
try {
// http client
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
// Checking http request method type
if (method == POST) {
HttpPost httpPost = new HttpPost(url);
// adding post params
if (params != null) {
httpPost.setEntity(new UrlEncodedFormEntity(params));
}
httpResponse = httpClient.execute(httpPost);
} else if (method == GET) {
// appending params to url
if (params != null) {
String paramString = URLEncodedUtils
.format(params, "utf-8");
url += "?" + paramString;
}
HttpGet httpGet = new HttpGet(url);
httpResponse = httpClient.execute(httpGet);
}
httpEntity = httpResponse.getEntity();
response = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
}

First of all, this format will refer to the V1 free version. World Weather Online has released v2, which is superior. I was in the process of updating and saw this question sitting out there so I'll answer based off of what I had that did work.
You are on the right track to use the AsyncTask, here is my call to AsyncTask. You should know I use my "DataPoint" class to simply contain the data from WWO that I need to use. Based on your question, you can show the data that I will put in the DataPoint object in anyway you see fit on the screen, since at the end of the queryWeatherService(), you will end up with a parsed set of data.
//Some call to query the weather, which executes the AsyncTask
private DataPoint queryWeatherService()
{
// This method will retrieve the data from the weather service
DataPoint newDataPoint = new DataPoint();
if (!waiting)
{
try{
newDataPoint = new WeatherServiceClass().execute(
String.valueOf(getlatitude()), //Not shown here: pass in some String of a float value of of your lat coordinate.
String.valueOf(getlongitude())) //Not shown here: pass in some String of a float value of of your long coordinate.
.get();
} catch (InterruptedException | ExecutionException e)
{
e.printStackTrace();
}
}
return newDataPoint;
// Documentation:
// https://developer.worldweatheronline.com/page/documentation
}
The WeatherServiceClass that extends the AsyncTask
public class WeatherServiceClass extends AsyncTask<String, String, DataPoint> {
private String latitude;
private String longitude;
public WeatherServiceClass() {
}
#Override
protected DataPoint doInBackground(String... params) {
DataPoint dp = new DataPoint();
JSONWeatherParser jparser = new JSONWeatherParser();
latitude = params[0];
longitude = params[1];
String data = ((new WeatherHttpClient().getWeatherData(latitude, longitude)));
try {
dp = jparser.getWeather(data);
} catch (JSONException e) {
e.printStackTrace();
}
return dp;
//Reference:
// http://www.javacodegeeks.com/2013/06/android-build-real-weather-app-json-http-and-openweathermap.html
}
}
Here is the WeatherHttpClient class:
public class WeatherHttpClient {
private static String BASE_URL = "http://api.worldweatheronline.com/free/v1/weather.ashx?q=";
private static String BASE_URL_PT2 = "&format=json&num_of_days=5&date=today&key=[ENTER YOUR KEY HERE, I'M NOT GIVING YOU MINE]";
public String getWeatherData(String latitude, String longitude){
HttpURLConnection con = null;
InputStream is=null;
try{
con = (HttpURLConnection)(new URL(BASE_URL + latitude+","+longitude+BASE_URL_PT2)).openConnection();
con.setRequestMethod("GET");
con.setDoInput(true);
con.setDoOutput(true);
con.connect();
//Reading the response
StringBuffer buffer = new StringBuffer();
is = con.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line = null;
while ((line=br.readLine()) != null)
buffer.append(line + "\r\n");
is.close();
con.disconnect();
return buffer.toString();
}
catch(Throwable t) {
t.printStackTrace();
}
finally {
try { is.close();} catch(Throwable t){}
try { con.disconnect();} catch(Throwable t){}
}
return null;
}
Finally, here is my JSONWeatherParser:
public class JSONWeatherParser {
public JSONWeatherParser() {
}
public DataPoint getWeather(String data) throws JSONException {
DataPoint dp = new DataPoint();
Weather weather = new Weather(); //This is just a class that has a bunch of strings in it for the weather info.
JSONObject jObj = new JSONObject(data);
//Parsing JSON data
JSONObject dObj = jObj.getJSONObject("data");
JSONArray cArr = dObj.getJSONArray("current_condition");
JSONObject JSONCurrent = cArr.getJSONObject(0);
weather.setCurrent_temp(getString("temp_F",JSONCurrent));
weather.setHour(getString("observation_time",JSONCurrent));
JSONArray jArr = dObj.getJSONArray("weather");
JSONObject JSONWeather = jArr.getJSONObject(0);
JSONArray jArrIcon = JSONWeather.getJSONArray("weatherIconUrl");
JSONObject JSONIcon = jArrIcon.getJSONObject(0);
weather.setDate(getString("date",JSONWeather));
weather.setPrecipmm(getString("precipMM",JSONWeather));
weather.setTempMaxc(getString("tempMaxC",JSONWeather));
weather.setTempMaxf(getString("tempMaxF",JSONWeather));
weather.setTempMinf(getString("tempMinF",JSONWeather));
weather.setTempMinc(getString("tempMinC",JSONWeather));
weather.setWeatherCode(getString("weatherCode",JSONWeather));
weather.setWeatherIconURL(getString("value",JSONIcon));
weather.setWinddir16point(getString("winddir16Point",JSONWeather));
weather.setWinddirDegree(getString("winddirDegree",JSONWeather));
weather.setWindspeedKmph(getString("windspeedKmph",JSONWeather));
weather.setWindspeedMiles(getString("windspeedMiles",JSONWeather));
dp.setWeather(weather); //assigns and converts the relevant weather strings to DataPoint
// For details of these operations and how each works go here:
// http://www.javacodegeeks.com/2013/06/android-build-real-weather-app-json-http-and-openweathermap.html
return dp;
}
private static String getString(String tagName, JSONObject jObj)
throws JSONException {
return jObj.getString(tagName);
}
}

Issue in passing a string from one activity to another

Background : I am trying to develop my first android application which is a student discussion panel. I am good with PHP and MySQL but don't have much experience in android Java.
Issue:
In SelectedQuestionActivity class, if I simply give the URL as http://thewbs.getfreehosting.co.uk/talky/fetchans.php?qid=3, it works just fine and it fetches the corresponding answer to the question.
But if I do it the way I have shown in the code below, the application crashes. I am not sure where I am wrong.
CODE:
AllQuestionActivity.java
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// getting values from selected ListItem
String pid = ((TextView) view.findViewById(R.id.qid)).getText()
.toString();
//pid is the value of the selected question for example www.example.com/fetchans?qid=3 so here pid value is supposed to be 3.
// Starting new intent
Intent in = new Intent(getApplicationContext(),
SelectedQuestionActivity.class);
// sending pid to next activity
in.putExtra(TAG_PID, pid);
startActivity(in);
}
});
Now in SelectedQuestionActivity.java
code:
public class SelectedQuestionActivity extends ListActivity {
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> productsList;
Intent intent = getIntent();
String qid = intent.getExtras().getString(TAG_PID);
// url to get all products list
private String url_all_products = "http://thewbs.getfreehosting.co.uk/talky/fetchans.php?qid="+qid;
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCTS = "ques";
private static final String TAG_PID = "aid";
private static final String TAG_NAME = "aname";
private static final String TAG_INFO = "answer";
private static final String TAG_DATE = "date";
// products JSONArray
JSONArray products = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_ans);
// Hashmap for ListView
productsList = new ArrayList<HashMap<String, String>>();
// Loading products in Background Thread
new LoadAllProducts().execute();
// Get listview
ListView lv = getListView();
}
class LoadAllProducts extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(SelectedQuestionActivity.this);
pDialog.setMessage("Loading Answers. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);
// Check your log cat for JSON reponse
Log.d("All Answers: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
products = json.getJSONArray(TAG_PRODUCTS);
// looping through All Products
for (int i = 0; i < products.length(); i++) {
JSONObject c = products.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_PID);
String name = c.getString(TAG_NAME);
String info = c.getString(TAG_INFO);
String date = c.getString(TAG_DATE);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_PID, id);
map.put(TAG_NAME, name);
map.put(TAG_INFO, info);
map.put(TAG_DATE, date);
// adding HashList to ArrayList
productsList.add(map);
}
}
else {
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting all products
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
SelectedQuestionActivity.this, productsList,
R.layout.list_selected_ques, new String[] { TAG_PID,
TAG_NAME, TAG_INFO, TAG_DATE },
new int[] { R.id.aid, R.id.aname, R.id.answer, R.id.date});
// updating listview
setListAdapter(adapter);
}
});
}
}
}
JSONparser.java
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET method
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}

Currently you are trying to getIntent outside onCreate of ListActivity so move it inside onCreate method as :
Intent intent;
String qid;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_ans);
// get Intent here
intent = getIntent();
qid = intent.getExtras().getString(TAG_PID);
// your code here
and also no need to use runOnUiThread method for updating UI from onPostExecute because onPostExecute method called on Ui thread we can access UI elements in it
EDIT:-
you are not adding any paramter to NameValuePair inside doInBackground . add quid before sending it to makeHttpRequest as :
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
add quid param here
params.add(new BasicNameValuePair("qid",qid)); //<<<< add here
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(
url_all_products,
"GET",
params);
// your code here

You are passing a string from one activity object to another , while you didn't write code to receive it on the new activity in the right place.
To solve this you should add some code to your onCreate:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_ans);
String url = getIntent().getStringExtra(TAG_PID);
if (url != null)
url_all_products = url;

You should need to get your intent values in onCreate() as below :
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_ans);
Intent intent = getIntent();
String qid = intent.getExtras().getString(TAG_PID);
}

NetworkOnMainThereadException when activating a new activity from MainActivity to display details about a list item

Whenever I run and click on a list item in my MainActivity to initiate DetailsActivity that is suppose to diaply a little more info about the selected list item(name, description) LogCat throws the following at me:
E/AndroidRuntime(678): at
com.example.myfirstapp.JSONParser.makeHttpRequest(JSONParser.java:61)
E/AndroidRuntime(678): at
com.example.myfirstapp.DetailsActivity$GetProductDetails$1.run(DetailsActivity.java:93)
Line 61(JSONParser): HttpResponse httpResponse = httpClient.execute(httpGet);
Line 93(DetailsActivity): JSONObject json = jsonParser.makeHttpRequest(
url_car_details, "GET", params);
DetailsActivity:
package com.example.myfirstapp;
/*
* ...imports...
*/
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET method
public JSONObject makeHttpRequest(String url, String method, List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
JSONParser:
package com.example.myfirstapp;
/*
* ...imports...
*/
public class DetailsActivity extends Activity {
TextView lblTitle;
TextView lblDesc;
String id;
// Progress Dialog
private ProgressDialog pDialog;
// JSON parser class
JSONParser jsonParser = new JSONParser();
// single product url
private static final String url_car_details = "http://10.0.2.2/webservice/get_car_details.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_CAR = "car";
private static final String TAG_ID = "id";
private static final String TAG_NAME = "name";
private static final String TAG_DESC = "description";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_details);
// getting product details from intent
Intent i = getIntent();
// getting product id (pid) from intent
id = i.getStringExtra(TAG_ID);
// Getting complete product details in background thread
new GetProductDetails().execute();
}
/**
* Background Async Task to Get complete product details
* */
class GetProductDetails extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(DetailsActivity.this);
pDialog.setMessage("Loading car details. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
/**
* Getting product details in background thread
* */
protected String doInBackground(String... params) {
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
// Check for success tag
int success;
try {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("id", id));
// getting product details by making HTTP request
// Note that product details url will use GET request
JSONObject json = jsonParser.makeHttpRequest(
url_car_details, "GET", params);
// check your log for json response
Log.d("Single Car Details", json.toString());
// json success tag
success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// successfully received product details
JSONArray productObj = json
.getJSONArray(TAG_CAR); // JSON Array
// get first product object from JSON Array
JSONObject product = productObj.getJSONObject(0);
// product with this pid found
// Edit Text
lblTitle = (TextView) findViewById(R.id.lblTitle);
lblDesc = (TextView) findViewById(R.id.lblDesc);
// display product data in EditText
lblTitle.setText(product.getString(TAG_NAME));
lblDesc.setText(product.getString(TAG_DESCRIPTION));
}else{
// product with pid not found
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once got all details
pDialog.dismiss();
}
}
}

What Luksprog said, this is missing the point:
protected String doInBackground(String... params) {
// updating UI from Background Thread
runOnUiThread(new Runnable() {
Move the code that needs to update the UI to onPostExecute(). Basically save the retrieved data in a variable and "return" it.

Chnage your code as:
/**
* Background Async Task to Get complete product details
* */
class GetProductDetails extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(DetailsActivity.this);
pDialog.setMessage("Loading car details. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
/**
* Getting product details in background thread
* */
protected String doInBackground(String... params) {
// Check for success tag
int success;
try {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("id", id));
// getting product details by making HTTP request
// Note that product details url will use GET request
JSONObject json = jsonParser.makeHttpRequest(
url_car_details, "GET", params);
// check your log for json response
Log.d("Single Car Details", json.toString());
// json success tag
success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// successfully received product details
JSONArray productObj = json
.getJSONArray(TAG_CAR); // JSON Array
// get first product object from JSON Array
JSONObject product = productObj.getJSONObject(0);
// updating UI from Background Thread
DetailsActivity.this.runOnUiThread(new Runnable() {
#Override
public void run() {
// product with this pid found
// Edit Text
lblTitle = (TextView) findViewById(R.id.lblTitle);
lblDesc = (TextView) findViewById(R.id.lblDesc);
// display product data in EditText
lblTitle.setText(product.getString(TAG_NAME));
lblDesc.setText(product.getString(TAG_DESCRIPTION));
}else{
// product with pid not found
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once got all details
pDialog.dismiss();
}
}
}
Second solution is remove runOnUiThread from doInBackground and move all Ui elememts inside onPostExecuteof AsyncTask. because onPostExecute get called when doInBackground done given task completely and you are able to access all UI elements inside onPostExecute