Because my json source is sometimes too long, and my android app crashes if it takes too long to load, i want to modify my code, so that when the user scrolls down to automaticaly load data or if is more simple, i would ike to add a button "Load More". Here is my existing code. What is the part i must modify for adding autoload or maybe a "Load More" button? Thanks!
package com.radioxxx.aacplay;
import android.app.DownloadManager;
import android.app.Fragment;
import android.app.ListFragment;
import android.app.ProgressDialog;
import android.content.Context;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListAdapter;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class FazeNoi extends ListFragment {
JSONParser2 jsonParser = new JSONParser2();
private ProgressDialog pDialog;
ArrayList<HashMap<String, String>> tracksList;
JSONArray albums = null;
String nume_piesa, cale;
String titlu;
private static final String URL_ALBUMS = "http://www.radioxxx.ro/json-news";
private static final String TAG_TITLU = "Titlu";
private static final String TAG_POZA = "FazeNoiID";
private static final String TAG_NUME = "CMSdate";
private static final String TAG_CALE = "URL";
#Override
public void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
tracksList = new ArrayList<HashMap<String, String>>();
new LoadTracks().execute();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_fazenoi, container, false);
return rootView;
}
class LoadTracks extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Se incarca ...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args) {
List<NameValuePair> params = new ArrayList<NameValuePair>();
//params.add(new BasicNameValuePair(TAG_ID, album_id));
String json = jsonParser.makeHttpRequest(URL_ALBUMS, "GET",
params);
Log.d("Track List JSON: ", json);
try {
JSONArray albums = new JSONArray(json);
for (int i = 0; i < albums.length(); i++) {
JSONObject c = albums.getJSONObject(i);
//String poza = c.getJSONArray("PozaPrincipalaMedia").getJSONObject(0).getString("thumb");
String track_no = String.valueOf(i + 1);
String poza = c.getJSONObject("PozaPrincipalaMedia").getString("thumb");
String idpoza = c.getJSONObject("PozaPrincipalaMedia").getString("id");
String nume = c.getString(TAG_TITLU);
String cale = c.getString(TAG_CALE);
HashMap<String, String> map = new HashMap<String, String>();
map.put("track_no", track_no + ".");
map.put(TAG_POZA, poza);
map.put(TAG_NUME, nume);
map.put(TAG_CALE, cale);
tracksList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String file_url) {
pDialog.dismiss();
getActivity().runOnUiThread(new Runnable() {
public void run() {
ListAdapter adapter = new SimpleAdapter(
getActivity(), tracksList,
R.layout.list_faze, new String[] {TAG_POZA, "track_no", TAG_NUME }, new int[] {
R.id.list_image,
R.id.track_no, R.id.nume_piesa });
setListAdapter(adapter);
//TextView text = (TextView) getActivity().findViewById(R.id.version);
//text.setText(titlu);
}
});
}
}
}
I'm going to post my comment as an answer, I believe it's the easiest way to quickly solve your problem. If you can control how much JSON is being sent on the server side, then make requests from your java app for page 1, page 2 etc.
Page 1,page 2,etc... could just send out small portions of the JSON you need, then attach a listener (button/scrollview) to request the next page, so on an so forth. Hope this helps!
Related
This is my code for getting the data from JSON, it will contain only one row,
but it will give output for only "pro_name" for left of the values it will give just dots(......).
package com.example.sh_enterprises;
import android.app.ProgressDialog;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.CardView;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.List;
public class Detailes extends AppCompatActivity {
//this is the JSON Data URL
//make sure you are using the correct ip else it will not work
public static String URL_PRODUCTS, pass1,pass2 ;
public static String ptopic,psubcode;
private static ProgressDialog progressDialog;
//a list to store all the products
List<pro_data> productList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detailes);
Intent i = getIntent();
pass1 = i.getStringExtra("pro_id");
//Toast.makeText(this,"HI THIS IS "+pass,Toast.LENGTH_SHORT).show();
//URL_PRODUCTS = "https://premnathindia.000webhostapp.com/Api.php?p1="+pass;
URL_PRODUCTS = "http://192.168.225.25/prem/Api.php?p1="+pass1+"&p2=det";
Toast.makeText(this, URL_PRODUCTS, Toast.LENGTH_SHORT).show();
productList = new ArrayList<>();
//this method will fetch and parse json
//to display it in recyclerview
loadProducts();
}
private void loadProducts() {
prefConfig product = new prefConfig(this);
String str = product.read_ret_id();
Toast.makeText(this,str,Toast.LENGTH_SHORT).show();
progressDialog = new ProgressDialog(this);
progressDialog.setMessage("Please wait...");
progressDialog.show();
/*
* Creating a String Request
* The request type is GET defined by first parameter
* The URL is defined in the second parameter
* Then we have a Response Listener and a Error Listener
* In response listener we will get the JSON response as a String
* */
StringRequest stringRequest = new StringRequest(Request.Method.GET, URL_PRODUCTS,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
//converting the string to json array object
JSONArray array = new JSONArray(response);
//traversing through all the object
for (int i = 0; i < 1; i++) {
//getting product object from json array
JSONObject product = array.getJSONObject(i);
product.getString("pro_id");
String st;
TextView a = findViewById(R.id.pro_name);
TextView b = findViewById(R.id.weight);
TextView c = findViewById(R.id.base_amount);
TextView d = findViewById(R.id.mass_amonut);
TextView e = findViewById(R.id.brand);
TextView f = findViewById(R.id.catogery);
String st1 = product.getString("pro_name");
a.setText(st1);
st = product.getString("weight");
b.setText(st);
st = product.getString("total_amount");
d.setText(st);
//st = product.getString("pro_img_url");
st = product.getString("base_amount");
c.setText(st);
//st = product.getString("disc");
st = product.getString("brands");
e.setText(st);
st = product.getString("categories");
f.setText(st);
}
progressDialog.dismiss();
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
//adding our stringrequest to queue
Volley.newRequestQueue(this).add(stringRequest);
}
public void downme_ooi(View view) {
String pro_id = ((TextView) view).getText().toString();
Intent i = new Intent(this,Detailes.class);
i.putExtra("pro_id",pro_id);
startActivity(i);
}
public void go_back(View view) {
super.onBackPressed();
}
}
Sorry I made the Mistake that in TextView I put the text as password .
I am trying to use the ProductHunt API to display a list of new posts in a ListView and further expand the list item on click.
On opening the app, the Progress bar appears but after that the app screen stays blank. I think there might be some error in my OnPostExecute method, because when I added a textview to display a string, its getting displayed but my listView is not getting displayed.
I used the standard Apache HttpClient for handling api requests.
I have 4 classes,
MainActivity.java
package com.emoji.apisoup;
/**
* Created by mdhalim on 16/05/16.
*/
import java.io.IOException;
import java.util.ArrayList;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import org.apache.http.HttpClientConnection;
import org.apache.http.HttpResponse;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicHttpResponse;
import org.apache.http.protocol.HTTP;
public class MainActivity extends Activity {
private ListView lvPosts;
private ProductHuntAdapter adapterPosts;
public static final String POST_DETAIL_KEY = "posts";
private ProgressDialog pDialog;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.phunt_main);
String serverURL = "https://api.producthunt.com/v1/posts/";
ArrayList<ProductHuntList> aPosts = new ArrayList<ProductHuntList>();
adapterPosts = new ProductHuntAdapter(MainActivity.this, aPosts);
lvPosts = (ListView) findViewById(R.id.lvPosts);
lvPosts.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
{
Intent i = new Intent(MainActivity.this, ProductHuntDetail.class);
i.putExtra(POST_DETAIL_KEY, adapterPosts.getItem(position));
startActivity(i);
}
}
});
new LongOperation().execute(serverURL);
}
private class LongOperation extends AsyncTask<String, Void, Void> {
private final HttpClient Content = new DefaultHttpClient();
private String Error = null;
#Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
protected Void doInBackground(String... urls){
JSONArray items = null;
try {
HttpGet httpget = new HttpGet(urls[0]);
httpget.setHeader("Accept","application/json");
httpget.setHeader("Content-Type","application/json");
httpget.setHeader("Authorization","Bearer 2587aa878d7334e3c89794a6b73ebffb59a06c23b82cd0f789d2ab72d2417739");
ResponseHandler<String> responseHandler = new BasicResponseHandler();
String jsonStr = Content.execute(httpget, responseHandler);
Log.d("Response: ", "> " + jsonStr);
JSONObject jsonObj = new JSONObject(jsonStr);
items = jsonObj.getJSONArray("posts");
// Parse json array into array of model objects
ArrayList<ProductHuntList> posts = ProductHuntList.fromJson(items);
// Load model objects into the adapter
for (ProductHuntList post : posts) {
adapterPosts.add(post);
}
} catch (JSONException e) {
e.printStackTrace();
} catch (IOException e) {
Error = e.getMessage();
cancel(true);
}
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
ArrayList<ProductHuntList> aPosts = new ArrayList<ProductHuntList>();
adapterPosts = new ProductHuntAdapter(MainActivity.this, aPosts);
lvPosts.setAdapter(adapterPosts);
}
}
}
ProductHuntList.java containing the JSON Data model and deserializer and a static method for parsing an array of JSON
package com.emoji.apisoup;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.io.Serializable;
/**
* Created by mdhalim on 18/05/16.
*/
public class ProductHuntList implements Serializable {
private static final long serialVersionUID = -8959832007991513854L;
private String name;
private String tagline;
private String screenshot_url;
private String largePosterUrl;
private String discussion_Url;
private String created_at;
private int votes_count;
public String getNames() {
return name;
}
public String getCreated_at() {
return created_at;
}
public String getScreenshot_url() {
return screenshot_url;
}
public String getDiscussion_Url() {
return discussion_Url;
}
public int getVotes_count() {
return votes_count;
}
public String getLargePosterUrl() {
return largePosterUrl;
}
public String getTagline(){
return tagline;
}
public static ProductHuntList fromJson(JSONObject jsonObject) {
ProductHuntList b = new ProductHuntList();
try {
// Deserialize json into object fields
b.name = jsonObject.getString("name");
b.created_at = jsonObject.getString("created_at");
b.tagline = jsonObject.getString("tagline");
b.screenshot_url = jsonObject.getJSONObject("screenshot_url").getString("300px");
b.largePosterUrl = jsonObject.getJSONObject("screenshot_url").getString("850px");
b.votes_count = jsonObject.getInt("votes_count");
b.discussion_Url = jsonObject.getString("discussion_url");
} catch (JSONException e) {
e.printStackTrace();
return null;
}
// Return new object
return b;
}
public static ArrayList<ProductHuntList> fromJson(JSONArray jsonArray) {
ArrayList<ProductHuntList> posts = new ArrayList<ProductHuntList>(jsonArray.length());
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject productJson = null;
try {
productJson = jsonArray.getJSONObject(i);
} catch (Exception e) {
e.printStackTrace();
continue;
}
ProductHuntList post = ProductHuntList.fromJson(productJson);
if (post != null)
{
posts.add(post);
}
}
return posts;
}
}
ProductHuntAdapter.java this implements the ArrayAdapter
package com.emoji.apisoup;
/**
* Created by mdhalim on 18/05/16.
*/
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import com.squareup.picasso.Picasso;
import java.util.ArrayList;
/**
* Created by mdhalim on 18/05/16.
*/
public class ProductHuntAdapter extends ArrayAdapter<ProductHuntList> {
public ProductHuntAdapter(Context context, ArrayList<ProductHuntList> aPosts) {
super(context, 0, aPosts);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// Get the data item for this position
ProductHuntList posts = getItem(position);
// Check if an existing view is being reused, otherwise inflate the view
if (convertView == null) {
LayoutInflater inflater = LayoutInflater.from(getContext());
convertView = inflater.inflate(R.layout.item_product_hunt, null);
}
// Lookup view for data population
TextView name = (TextView) convertView.findViewById(R.id.name);
TextView created = (TextView) convertView.findViewById(R.id.created);
TextView tagline = (TextView) convertView.findViewById(R.id.tagline);
ImageView ivPosterImage = (ImageView) convertView.findViewById(R.id.ivPosterImage);
// Populate the data into the template view using the data object
name.setText(posts.getNames());
created.setText("Created On: " + posts.getCreated_at() + "%");
tagline.setText(posts.getTagline());
Picasso.with(getContext()).load(posts.getScreenshot_url()).into(ivPosterImage);
// Return the completed view to render on screen
return convertView;
}
}
and finally, a class implementing the activity for Item Details when a user clicks on any item on the list.
ProductHuntDetail
package com.emoji.apisoup;
/**
* Created by mdhalim on 18/05/16.
*/
import android.annotation.SuppressLint;
import android.app.Activity;
import android.os.Bundle;
import android.text.Html;
import android.widget.ImageView;
import android.widget.TextView;
import com.squareup.picasso.Picasso;
public class ProductHuntDetail extends Activity {
private ImageView ivPosterImage;
private TextView name;
private TextView discusUrl;
private TextView upvotes;
private TextView tagline;
private TextView created;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.product_hunt_detail);
// Fetch views
ivPosterImage = (ImageView) findViewById(R.id.ivPosterImage);
name = (TextView) findViewById(R.id.name);
discusUrl = (TextView) findViewById(R.id.discusUrl);
created = (TextView) findViewById(R.id.created);
upvotes = (TextView) findViewById(R.id.upvotes);
tagline = (TextView) findViewById(R.id.tagline);
// Load movie data
ProductHuntList posts = (ProductHuntList) getIntent().getSerializableExtra(MainActivity.POST_DETAIL_KEY);
loadMovie(posts);
}
// Populate the data for the movie
#SuppressLint("NewApi")
public void loadMovie(ProductHuntList posts) {
// Populate data
name.setText(posts.getNames());
upvotes.setText(Html.fromHtml("<b>Upvotes:</b> " + posts.getVotes_count() + "%"));
created.setText(posts.getCreated_at());
tagline.setText(posts.getTagline());
discusUrl.setText(Html.fromHtml("<b>Discussion Url:</b> " + posts.getDiscussion_Url()));
// R.drawable.large_movie_poster from
// http://content8.flixster.com/movie/11/15/86/11158674_pro.jpg -->
Picasso.with(this).load(posts.getLargePosterUrl()).
placeholder(R.drawable.large_movie_poster).
into(ivPosterImage);
}
}
I have been trying to debug this for hours :/
Your Async task is returning a void.
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
ArrayList<ProductHuntList> aPosts = new ArrayList<ProductHuntList>();
adapterPosts = new ProductHuntAdapter(MainActivity.this, aPosts);
lvPosts.setAdapter(adapterPosts);
}
As far as I can tell from the code, aPosts is empty.
I think your Async task should be -
AsyncTask<String, Void, ProductHuntAdapter>
and remove -
adapterPosts = new ProductHuntAdapter(MainActivity.this, aPosts);
You are creating and updating this in your doInBackground() method already.
I got it!
I didnt need to declare these lines again in my onPostExecute() method
ArrayList<ProductHuntList> aPosts = new ArrayList<ProductHuntList>();
adapterPosts = new ProductHuntAdapter(MainActivity.this, aPosts);
So bascially, my new onPostExecute() method goes like this
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
lvPosts.setAdapter(adapterPosts);
}
I had been trying to find this error for last 2 hours, it was harder since, I wasn't even getting any errors. As soon as I posted it on StackOverFlow, seems like I had a divine intervention.
I used this code to connect to MySQL using WAMP.
But it doesn't work
package com.first.ismael.material_drawer;
import android.app.Activity;
import android.app.Fragment;
import android.app.ListFragment;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.*;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import android.widget.Toast;
/**
* Created by ismae_000 on 11/20/2015.
*/
public class all_meals extends Fragment {
public ProgressDialog pDialog ;
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
// url to get all products list
private static String url_all_products = "http://192.168.1.7/get_all_products.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCTS = "component";
private static final String TAG_PID = "id";
private static final String TAG_NAME = "name";
private static final String TAG_TYPE ="type";
ListView lv;
// products JSONArray
JSONArray products = null;
ArrayList<HashMap<String, String>> productsList;
// url to get all products list
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.all,
container, false);
productsList = new ArrayList<HashMap<String, String>>();
lv = (ListView)view.findViewById(R.id.listView2);
// Loading products in Background Thread
new LoadAllProducts().execute();
// Get listview
return view;
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
class LoadAllProducts extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Loading products. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
/**
* getting All products from url
* */
#Override
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
Toast.makeText(getActivity(),"There is nothing",Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
#Override
protected void onPostExecute(String file_url) {
pDialog.dismiss();
// updating UI from Background Thread
getActivity().runOnUiThread(new Runnable() {
public void run() {
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
getActivity(), productsList,
R.layout.list_item, new String[]{TAG_PID,
TAG_NAME},
new int[]{R.id.pid, R.id.name});
// updating listview
lv.setAdapter(adapter);
}
});
}
}
}
I used it in a Fragment.
Please help
If you are using WAMP means using localhost for database MySql. Ip address for localhost should 10.0.2.2 not 192.168.1.7
try to replace
_http://192.168.1.7/get_all_products.php
with
_http://10.0.2.2/get_all_products.php
and check your output get_all_products.php, that's should be json format
read this
- why do we use 10.0.2.2 to connect to local web server instead of using computer ip address in android client
check json format use this
- _http://jsonlint.com
a real amateur developer here in dire need of some assistance. I've been trying to parse JSON data and turn it into a list of items, but I am having difficulties attempting to use the setListAdapter method despite importing it into the class. Any help would be massively appreciated.
Here is my main activity, error is in the onPostExecute method
import java.io.IOException;
import java.util.List;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpGet;
import android.app.Activity;
import android.net.http.AndroidHttpClient;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.widget.ArrayAdapter;
public class JSON extends Activity {
// Coordinates used for centering the Map
private final static String UNAME = "aporter";
private final static String URL = "http://api.geonames.org/earthquakesJSON?north=44.1&south=-9.9&east=-22.4&west=55.2&username="
+ UNAME;
public static final String TAG = "MapsEarthquakeMapActivity";
// Set up UI and get earthquake data
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
new HttpGetTask().execute(URL);
}
private class HttpGetTask extends
AsyncTask<String, Void, List<GeonameRec>> {
AndroidHttpClient mClient = AndroidHttpClient.newInstance("");
#Override
protected List<GeonameRec> doInBackground(String... params) {
HttpGet request = new HttpGet(params[0]);
JSONResponseHandler responseHandler = new JSONResponseHandler();
try {
// Get Earthquake data in JSON format
// Parse data into a list of EarthQuakeRecs
return mClient.execute(request, responseHandler);
} catch (ClientProtocolException e) {
Log.i(TAG, "ClientProtocolException");
} catch (IOException e) {
Log.i(TAG, "IOException");
}
return null;
}
#Override
protected void onPostExecute(List<GeonameRec> result) {
if (null != mClient)
mClient.close();
setListAdapter(new ArrayAdapter<String>(
JSON.this,
R.layout.listitem, result));
}
}
}
}
And here is my class where I format the JSON response.
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.ResponseHandler;
import org.apache.http.impl.client.BasicResponseHandler;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONTokener;
public class JSONResponseHandler implements
ResponseHandler<List<GeonameRec>> {
#Override
public List<GeonameRec> handleResponse(HttpResponse response)
throws ClientProtocolException, IOException {
List<GeonameRec> result = new ArrayList<GeonameRec>();
String JSONResponse = new BasicResponseHandler()
.handleResponse(response);
try {
JSONObject object = (JSONObject) new JSONTokener(JSONResponse)
.nextValue();
JSONArray earthquakes = object.getJSONArray("earthquakes");
for (int i = 0; i < earthquakes.length(); i++) {
JSONObject tmp = (JSONObject) earthquakes.get(i);
result.add(new GeonameRec(
tmp.getDouble("lat"),
tmp.getDouble("lng")));
}
} catch (JSONException e) {
e.printStackTrace();
}
return result;
}
}
setListAdapter method is available in ListActivity not in Activity.
to do so in an Activity sub class, you should define your ListView and call listView.setAdapter
I have to retrieve json object from json file from this url.
My code is throwing java.lang.RuntimeException in doInBackground() and string to jsonObject conversion exception.
Can anyone help me at this? I am new to Android programming.
package course.examples.networkingearthquake;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.os.AsyncTask;
import android.widget.Button;
import android.view.View;
import android.widget.TextView;
import android.widget.EditText;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.BasicResponseHandler;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONTokener;
import android.net.http.AndroidHttpClient;
public class HttpActivity extends ActionBarActivity {
TextView mTextView;
EditText etInput;
TextView input;
String number;//edited
int num;//edited
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_socket);
mTextView = (TextView)findViewById(R.id.text1);
input = (TextView)findViewById(R.id.input);
etInput = (EditText)findViewById(R.id.etInput);
input.setText("Input");
//number = etInput.getText().toS();
final Button btDisplay = (Button)findViewById(R.id.btDisplay);
btDisplay.setText("DISPLAY");
btDisplay.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
new HttpGetTask().execute();
}
});
}
private class HttpGetTask extends AsyncTask<Void, Void, String>{
private static final String TAG = "HttpGetTask";
private static final String URL = "http://earthquake.usgs.gov/earthquakes/feed/geojsonp/2.5/week";
AndroidHttpClient mClient = AndroidHttpClient.newInstance("");
#Override
protected String doInBackground(Void... params){
HttpGet request = new HttpGet(URL);
JSONResponseHandler responseHandler = new JSONResponseHandler();
// ResponseHandler<String> responseHandler = new BasicResponseHandler();
try{
return mClient.execute(request,responseHandler);
}catch(ClientProtocolException exception){
exception.printStackTrace();
}catch(IOException exception){
exception.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result){
if(null != mClient)
mClient.close();
mTextView.setText(result);
}
}
private class JSONResponseHandler implements ResponseHandler<String>{
#Override
public String handleResponse(HttpResponse response)
throws ClientProtocolException, IOException {
String result = null;
String JSONResponse = new BasicResponseHandler().handleResponse(response);
JSONResponse = JSONResponse.substring(17, JSONResponse.length()-3);
num = Integer.parseInt(number);// edited
try {
JSONObject responseObject = (JSONObject) new JSONTokener(
JSONResponse).nextValue();
JSONArray features = responseObject.getJSONArray("features");
JSONObject retObject = (JSONObject)features.get(num);//edited
// JSONObject geometry = (JSONObject)retObject.get("geometry");
result = retObject.toString();
} catch (JSONException e) {
e.printStackTrace();
}
return result;
}
}
The JSON returned by the URL you specify containts eqfeed_callback() which needs to be stripped in order to make it valid JSON.
It seems like you have done this in your response handler, but you are cutting off one character too much at both the start and the end.
Try this:
JSONResponse = JSONResponse.substring(16, JSONResponse.length()-2);