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Im doing some database work in my app, i want to pull all the locations from my web database and show it in my listview in the app. Ive created the “API” where the respons is Json.
The link where the json is: http://000100023.host56.com/db_all.php
Using this tutorial: http://www.androidhive.info/2012/05/how-to-connect-android-with-php-mysql/
The Logcat:
11-14 16:50:21.508: E/AndroidRuntime(22809): FATAL EXCEPTION: AsyncTask #1 11-14 16:50:21.508: E/AndroidRuntime(22809): Process: com.spxc.nightclubratings, PID: 22809 11-14 16:50:21.508: E/AndroidRuntime(22809): java.lang.RuntimeException: An error occured while executing doInBackground() 11-14 16:50:21.508: E/AndroidRuntime(22809): at android.os.AsyncTask$3.done(AsyncTask.java:300) 11-14 16:50:21.508: E/AndroidRuntime(22809): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355) 11-14 16:50:21.508: E/AndroidRuntime(22809): at java.util.concurrent.FutureTask.setException(FutureTask.java:222) 11-14 16:50:21.508: E/AndroidRuntime(22809): at java.util.concurrent.FutureTask.run(FutureTask.java:242) 11-14 16:50:21.508: E/AndroidRuntime(22809): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231) 11-14 16:50:21.508: E/AndroidRuntime(22809): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 11-14 16:50:21.508: E/AndroidRuntime(22809): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 11-14 16:50:21.508: E/AndroidRuntime(22809): at java.lang.Thread.run(Thread.java:841) 11-14 16:50:21.508: E/AndroidRuntime(22809): Caused by: java.lang.NullPointerException 11-14 16:50:21.508: E/AndroidRuntime(22809): at com.spxc.nightclubratings.SearchLocationActivity$LoadAllProducts.doInBackground(SearchLocationActivity.java:132) 11-14 16:50:21.508: E/AndroidRuntime(22809): at com.spxc.nightclubratings.SearchLocationActivity$LoadAllProducts.doInBackground(SearchLocationActivity.java:1) 11-14 16:50:21.508: E/AndroidRuntime(22809): at android.os.AsyncTask$2.call(AsyncTask.java:288) 11-14 16:50:21.508: E/AndroidRuntime(22809): at java.util.concurrent.FutureTask.run(FutureTask.java:237) 11-14 16:50:21.508: E/AndroidRuntime(22809): ... 4 more 11-14 16:50:22.199: E/WindowManager(22809): android.view.WindowLeaked: Activity com.spxc.nightclubratings.SearchLocationActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{42313208 V.E..... R......D 0,0-729,192} that was originally added here 11-14 16:50:22.199: E/WindowManager(22809): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:346) 11-14 16:50:22.199: E/WindowManager(22809): at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248) 11-14 16:50:22.199: E/WindowManager(22809): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.Dialog.show(Dialog.java:286) 11-14 16:50:22.199: E/WindowManager(22809): at com.spxc.nightclubratings.SearchLocationActivity$LoadAllProducts.onPreExecute(SearchLocationActivity.java:119) 11-14 16:50:22.199: E/WindowManager(22809): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587) 11-14 16:50:22.199: E/WindowManager(22809): at android.os.AsyncTask.execute(AsyncTask.java:535) 11-14 16:50:22.199: E/WindowManager(22809): at com.spxc.nightclubratings.SearchLocationActivity.onCreate(SearchLocationActivity.java:59) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.Activity.performCreate(Activity.java:5243) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2140) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.ActivityThread.access$700(ActivityThread.java:135) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397) 11-14 16:50:22.199: E/WindowManager(22809): at android.os.Handler.dispatchMessage(Handler.java:102) **11-14 16:50:22.199: E/WindowManager(22809): at android.os.Looper.loop(Looper.java:137) 11-14 16:50:22.199: E/WindowManager(22809): at android.app.ActivityThread.main(ActivityThread.java:4998) 11-14 16:50:22.199: E/WindowManager(22809): at java.lang.reflect.Method.invokeNative(Native Method) 11-14 16:50:22.199: E/WindowManager(22809): at java.lang.reflect.Method.invoke(Method.java:515) 11-14 16:50:22.199: E/WindowManager(22809): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777) 11-14 16:50:22.199: E/WindowManager(22809): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593) 11-14 16:50:22.199: E/WindowManager(22809): at dalvik.system.NativeStart.main(Native Method)
JsonParser: 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; } }
SearchLocationAcitivity:
public class SearchLocationActivity extends ListActivity { // Progress Dialog private ProgressDialog pDialog; // Creating JSON Parser object JSONParser jParser = new JSONParser(); ArrayList<HashMap<String, String>> productsList; // url to get all products list private static String url_all_products = "http://http://000100023.host56.com/db_all.php"; // JSON Node names private static final String TAG_SUCCESS = "success"; private static final String TAG_PRODUCTS = "locations"; private static final String TAG_PID = "id"; private static final String TAG_NAME = "name"; // products JSONArray JSONArray products = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_search_location); // Hashmap for ListView productsList = new ArrayList<HashMap<String, String>>(); // Loading products in Background Thread new LoadAllProducts().execute(); // Get listview ListView lv = getListView(); // on seleting single product // launching Edit Product Screen lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { // getting values from selected ListItem String pid = ((TextView) view.findViewById(R.id.pid)).getText() .toString(); // Starting new intent //Intent in = new Intent(getApplicationContext(), // EditProductActivity.class); // sending pid to next activity //in.putExtra(TAG_PID, pid); // starting new activity and expecting some response back //startActivityForResult(in, 100); } }); } // Response from Edit Product Activity @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); // if result code 100 if (resultCode == 100) { // if result code 100 is received // means user edited/deleted product // reload this screen again Intent intent = getIntent(); finish(); startActivity(intent); } } /** * Background Async Task to Load all product by making HTTP Request * */ class LoadAllProducts extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); pDialog = new ProgressDialog(SearchLocationActivity.this); pDialog.setMessage("Loading locations. Please wait..."); pDialog.setIndeterminate(false); pDialog.setCancelable(false); pDialog.show(); } /** * getting All products from url * */ 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 Products: ", json.toString()); try { // Checking for SUCCESS TAG int success = json.getInt(TAG_SUCCESS); if (success == 1) { // products found // Getting Array of Products 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); // 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); // adding HashList to ArrayList productsList.add(map); } } else { // no products found // Launch Add New product Activity //Intent i = new Intent(getApplicationContext(), // NewProductActivity.class); // Closing all previous activities //i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); //startActivity(i); } } 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( SearchLocationActivity.this, productsList, R.layout.list_item, new String[] { TAG_PID, TAG_NAME}, new int[] { R.id.pid, R.id.name }); // updating listview setListAdapter(adapter); } }); } } }
Any help is much appreciated!
Answer
your URL string is wrong, you wrote it like:
Private static String url_all_products = "http://http://000100023.host56.com/db_all.php";
it should be:
Private static String url_all_products = "http://000100023.host56.com/db_all.php";
one http://
is enough 😉
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