I am trying to make a simple GET request to my local NodeJS server to get some JSON objects. I changed the request so it happens as an AsyncTask rather than in the UI thread. But I am still not able to get it to work. Does this code look correct? Sorry, not great with Java yet.
package com.dd.relay;
import com.dd.relay.HttpRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import android.app.ListActivity;
import android.content.Context;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends ListActivity {
public final static String EXTRA_MESSAGE = "com.dd.relay.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// We'll define a custom screen layout here (the one shown above), but
// typically, you could just use the standard ListActivity layout.
setContentView(R.layout.activity_main);
// Make a GET request for data
String url = "http://localhost.com/contacts";
String res = null;
try {
HttpRequest request = new HttpRequest();
request.execute(new URL(url));
Log.v(EXTRA_MESSAGE, res);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
TextView textView = (TextView) findViewById(R.id.textv);
Context context = this.getApplicationContext();
Toast mytoast = Toast.makeText(context, res, Toast.LENGTH_LONG);
mytoast.show();
textView.setText(res);
// Create list for contacts
/* List<Map<String, RelayContact>> data = null;
// Now create a new list adapter bound to the cursor.
// SimpleListAdapter is designed for binding to a Cursor.
ListAdapter adapter = new SimpleAdapter(this, data, 0, new String[] {"First", "Number"}, new int[] {android.R.id.text1, android.R.id.text2}); // Parallel array of which template objects to bind to those columns.
// Bind to our new adapter.
this.setListAdapter(adapter);*/
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
And here is my custom HttpRequest AsyncTask class
package com.dd.relay;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import android.os.AsyncTask;
public class HttpRequest extends AsyncTask<URL, Void, Void> {
protected String doInBackground(URL url) throws Exception {
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
if (conn.getResponseCode() != 200) {
throw new IOException(conn.getResponseMessage());
}
// Buffer the result into a string
BufferedReader rd = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
StringBuilder sb = new StringBuilder();
String line;
while ((line = rd.readLine()) != null) {
sb.append(line);
}
rd.close();
conn.disconnect();
return sb.toString();
}
protected void onProgressUpdate(Integer progress) {
}
protected void onPostExecute(String result) {
System.out.println(result);
}
#Override
protected Void doInBackground(URL... arg0) {
// TODO Auto-generated method stub
return null;
}
}
Android does not allow network communication to be done on the UI thread. Android provides a class called AsyncTask that is intended for such interactions. See this link for details and one option for a solution (This is probably what you want):
How to fix android.os.NetworkOnMainThreadException?
or you can also create a custom class that extends Thread or implements Runnable that posts to the UI thread using a Handler
try this link hope use full to you :-
Verifying login details via http get : Android
public class LongOperation extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... params) {
// call function
login(userName, password);
return null;
}
#Override
protected void onPostExecute(String result) {
}
#Override
protected void onPreExecute() {
}
#Override
protected void onProgressUpdate(Void... values) {
}
}
Related
Hello Guys I received a a big problem in my project. I make the OkHttp request i receive response from server all is perfect. the problem is why i can't display data, i made a model item in xml and listview(this is the required view) and when i acces the page is blank.
Can anyone help me with this issue?
code for page is the following:
package com.example.socceraplication;
import static android.content.ContentValues.TAG;
import androidx.appcompat.app.AppCompatActivity;
import androidx.annotation.NonNull;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.SimpleAdapter;
import android.widget.Toast;
import com.google.gson.Gson;
import java.util.ArrayList;
import java.util.HashMap;
import java.io.IOException;
import java.util.List;
import java.util.concurrent.ExecutionException;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import okhttp3.ResponseBody;
import java.util.ArrayList;
public class TeamInfo extends AppCompatActivity {
private ListView lv;
ArrayList<HashMap<String, String>> resultList;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_team_info);
resultList = new ArrayList<>();
lv = (ListView) findViewById(R.id.list);
new GetContacts().execute();
}
private class GetContacts extends AsyncTask<Void, Void, Void>{
#Override
protected void onPreExecute() {
super.onPreExecute();
Toast.makeText(TeamInfo.this,"Json Data is downloading",Toast.LENGTH_LONG).show();
}
#Override
protected Void doInBackground(Void... arg0) {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url("https://heisenbug-premier-league-live-scores-v1.p.rapidapi.com/api/premierleague/team?name=Liverpool")
.get()
.addHeader("X-RapidAPI-Key", "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx")
.addHeader("X-RapidAPI-Host", "heisenbug-premier-league-live-scores-v1.p.rapidapi.com")
.build();
client.newCall(request).enqueue(new Callback() {
#Override
public void onFailure(#NonNull Call call, #NonNull IOException e) {
call.cancel();
}
#Override
public void onResponse(#NonNull Call call, #NonNull Response response) throws IOException {
String jsonStr=response.body().string();
Log.e(TAG, "Response from url: " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
JSONArray records = jsonObj.getJSONArray("records");
// looping through All items
for (int i = 0; i < records.length(); i++) {
JSONObject c = records.getJSONObject(i);
String league = c.getString("league");
String season = c.getString("season");
String name = c.getString("name");
String officialName = c.getString("officialName");
String address = c.getString("address");
String telephone = c.getString("telephone");
String fax = c.getString("fax");
String website = c.getString("website");
String founded = c.getString("founded");
String teamSize = c.getString("teamSize");
String averageAge = c.getString("averageAge");
String foreigners = c.getString("foreigners");
String nationaTeamPlayers = c.getString("nationaTeamPlayers");
String teamValue = c.getString("teamValue");
String venue = c.getString("venue");
String venueCapacity = c.getString("venueCapacity");
HashMap<String, String> result = new HashMap<>();
// adding each child node to HashMap key => value
result.put("league",league);
result.put("season",season);
result.put("name",name);
result.put("officialName",officialName);
result.put("address",address);
result.put("telephone",telephone);
result.put("fax",fax);
result.put("website",website);
result.put("founded",founded);
result.put("teamSize",teamSize);
result.put("averageAge",averageAge);
result.put("foreigners",foreigners);
result.put("nationaTeamPlayers",nationaTeamPlayers);
result.put("teamValue",teamValue);
result.put("venue",venue);
result.put("venueCapacity",venueCapacity);
resultList.add(result);
}
} catch (final JSONException e) {
Log.e(TAG, "Json parsing error: " + e.getMessage());
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),
"Json parsing error: " + e.getMessage(), Toast.LENGTH_LONG).show();
}
});
}
}else {
Log.e(TAG, "Couldn't get json from server.");
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),
"Couldn't get json from server. Check LogCat for possible errors!",
Toast.LENGTH_LONG).show();
}
});
}
}
});
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
ListAdapter adapter = new SimpleAdapter(TeamInfo.this, resultList,
R.layout.list_item_team, new String[]{ "league","season","name","officialName","address","telephone","fax","website","founded","teamSize","averageAge","foreigners","nationaTeamPlayers","teamValue","venue","venueCapacity"},
new int[]{R.id.league, R.id.season,R.id.name,R.id.officialName,R.id.address,R.id.telephone,R.id.fax,R.id.website,R.id.founded,R.id.teamSize,R.id.averageAge,R.id.foreigners,R.id.nationaTeamPlayers,R.id.teamValue,R.id.venue,R.id.venueCapacity});
lv.setAdapter(adapter);
}
}
}
The enqueue call is asynchronous, which means it queues up work to be run in the background at some point in the future, and when it is complete then it runs the callback you supply (onResponse). This means in your case the order of calls is
Start doInBackground
Add your Http call to the queue
Return from doInBackground
Run onPostExecute
Post empty list to the adapter
... some time later ...
Run the onResponse callback when it gets data
To fix this, you can remove the async task entirely and just queue the work from the main thread, since it already handles actually doing the request in the background.
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_team_info);
resultList = new ArrayList<>();
lv = (ListView) findViewById(R.id.list);
startRequest();
}
private void startRequest() {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
//...
.build();
client.newCall(request).enqueue(new Callback() {
#Override
public void onFailure(#NonNull Call call, #NonNull IOException e) {
call.cancel();
}
#Override
public void onResponse(#NonNull Call call, #NonNull Response response) {
showResult(response);
}
});
}
private void showResult(Response response) {
// show the result here - no need to runOnUiThread
// set the adapter, put text in views, etc from in here
}
If you really want to make the call from your own AsyncTask in the background, you should use the synchronous API, not the asynchronous API. This means calling execute instead of enqueue, like this:
// this MUST run on a background thread or it will block the UI thread
Response response = client.newCall(request).execute();
When I navigate to the activity that should load a ListView from a JSON hosted on AWS S3, I get nothing but a blank activity. There's no error message, no errors in the debugger, and Logcat doesn't seem to hold any relevant information.
Here's LoadJSONTask.java:
package com.teamplum.projectapple;
import android.os.AsyncTask;
import com.google.gson.Gson;
import com.google.gson.JsonSyntaxException;
import com.teamplum.projectapple.NewsDO;
import com.teamplum.projectapple.Response;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
public class LoadJSONTask extends AsyncTask<String, Void, Response> {
public LoadJSONTask(Listener listener) {
mListener = listener;
}
public interface Listener {
void onLoaded(List<NewsDO> androidList);
void onError();
}
private Listener mListener;
#Override
protected Response doInBackground(String... strings) {
try {
String stringResponse = loadJSON(strings[0]);
Gson gson = new Gson();
return gson.fromJson(stringResponse, Response.class);
} catch (IOException e) {
e.printStackTrace();
return null;
} catch (JsonSyntaxException e) {
e.printStackTrace();
return null;
}
}
#Override
protected void onPostExecute(Response response) {
if (response != null) {
mListener.onLoaded(response.getAndroid());
} else {
mListener.onError();
}
}
private String loadJSON(String jsonURL) throws IOException {
URL url = new URL(jsonURL);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("GET");
conn.setDoInput(true);
conn.connect();
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String line;
StringBuilder response = new StringBuilder();
while ((line = in.readLine()) != null) {
response.append(line);
}
in.close();
return response.toString();
}
}
and here's MainActivity.java:
package com.teamplum.projectapple;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;
//import com.teamplum.projectapple.NewsDO;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class MainActivity extends AppCompatActivity implements LoadJSONTask.Listener, AdapterView.OnItemClickListener {
private ListView mListView;
public static final String URL = "https://s3-eu-west-1.amazonaws.com/tyi-work/Work_Experience.json";
private List<HashMap<String, String>> mAndroidMapList = new ArrayList<>();
private static final String KEY_TIT = "title";
private static final String KEY_CAT = "category";
private static final String KEY_DES = "description";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mListView = findViewById(R.id.list_view);
mListView.setOnItemClickListener(this);
new LoadJSONTask(this).execute(URL);
}
#Override
public void onLoaded(List<NewsDO> androidList) {
for (NewsDO work : androidList) {
HashMap<String, String> map = new HashMap<>();
map.put(KEY_TIT, work.getTitle());
map.put(KEY_CAT, work.getCategory());
map.put(KEY_DES, work.getDescription());
mAndroidMapList.add(map);
}
loadListView();
}
#Override
public void onError() {
Toast.makeText(this, "Error !", Toast.LENGTH_SHORT).show();
}
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Toast.makeText(this, mAndroidMapList.get(i).get(KEY_TIT),Toast.LENGTH_LONG).show();
}
private void loadListView() {
ListAdapter adapter = new SimpleAdapter(MainActivity.this, mAndroidMapList, R.layout.list_item,
new String[] { KEY_CAT, KEY_TIT, KEY_DES },
new int[] { R.id.version,R.id.name, R.id.api });
mListView.setAdapter(adapter);
}
}
I used this tutorial to help make this, if you need any extra information please feel free to ask, thank you.
I have tested the async task for the URL connection and its working fine.
The problem is either on the parsing or on the activity side. Have you tried putting breakpoints and follow the data?
I'm building a currency converter (get from API, dynamically fills lists to create available currencies, select two currencies and return the rate. It seems a right of passage exercise).
I've been trying to get a Spinner to work, but despite my best efforts I can't seem to get the listener to do anything when I select a value from the list. When I do click a value, the logs do return something (see below), but I don't know what it means, and why it's not returning the System.out.println("yay") call I want.
D/OpenGLRenderer: endAllActiveAnimators on 0xa7040980
(DropDownListView) with handle 0x95c21270".
The array adapter is properly filling the spinner list from an ArrayList<string> I get get from API and a JSON Object. The listener code looks correct based on the examples I found on S.O. so far.
I wonder if it's an ordering issue in my code? Or something else.
package com.timlee.currencymate;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
public class MainActivity extends AppCompatActivity {
// public variables
String uRLResultString = "";
ArrayList <String> currencies = new ArrayList<String>();
Spinner currencyOneSpinner;
Spinner currencyTwoSpinner;
// get data from api
public class DownloadTask extends AsyncTask <String, Void, String> {
#Override
protected String doInBackground(String... urls) {
URL url;
HttpURLConnection urlConnection = null;
try {
url = new URL(urls[0]);
urlConnection = (HttpURLConnection)url.openConnection();
InputStream in = urlConnection.getInputStream();
InputStreamReader reader = new InputStreamReader(in);
int data = reader.read();
while (data != -1) {
char current = (char) data;
uRLResultString += current;
data = reader.read();
}
return uRLResultString;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
//System.out.println(result);
//if get current list then run this, else run something else
getCurrencyList();
}
}
//gets the list of currecies
public void getCurrencyList () {
try {
JSONObject jsonObject = new JSONObject(uRLResultString);
String base = jsonObject.getString("base");
String rates = jsonObject.getString("rates");
currencies.add(base);
System.out.println(rates);
JSONObject jSonObj = new JSONObject(rates);
Iterator<String> keys = jSonObj.keys();
while (keys.hasNext()) {
String key = (String)keys.next();
currencies.add(key);
if (jSonObj.get(key) instanceof JSONObject) {
}
}
Collections.sort(currencies, String.CASE_INSENSITIVE_ORDER);
} catch (JSONException e) {
e.printStackTrace();
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
currencies = new ArrayList<String>();
String currencyURL = "http://api.fixer.io/latest?base=AUD";
DownloadTask task = new DownloadTask();
task.execute(currencyURL);
// apply Array Adapter and listener
currencyOneSpinner = (Spinner)findViewById(R.id.spinnerCurrencyOne);
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<>(this,android.R.layout.simple_spinner_item,currencies);
currencyOneSpinner.setAdapter(arrayAdapter);
currencyOneSpinner.setOnItemSelectedListener (new OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
System.out.println("yay");
return;
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
System.out.println("neyh");
return;
}
});
}
}
You did not set a dropdown view for the adapter. Add this line above setOnItemCLickListener
currencyOneSpinner.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
And Since you're using an AsyncTask don't forget to call the below line everytime you update the list.
arrayAdapter.notifyDataSetChanged();
NOTE: You have to initialize the adapter globally.
I'm trying to call the function getUrlContents(string) inside my seismic_text.java file to my MainActivity.java file. How can I call the function from anywhere in the file? Any information or tip is appreciated. I include my files down below.
This is my MainActivity.java:
package bt.alfaquake;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.app.NotificationManager;
import android.content.Intent;
import android.view.View;
import android.app.PendingIntent;
import android.support.v7.app.ActionBarActivity;
import android.support.v4.app.NotificationCompat;
import bt.alfaquake.seismic_text;
public class MainActivity extends AppCompatActivity {
NotificationCompat.Builder notification;
private static final int uniqueID = 123;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
notification = new NotificationCompat.Builder(this);
}
}
This is my seismic_text.java:
package bt.alfaquake;
import java.net.*;
import java.io.*;
public class seismic_text {
public static String getUrlContents(String theUrl) {
StringBuilder content = new StringBuilder();
try
{
URL url = new URL(theUrl);
URLConnection urlConnection = url.openConnection();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
String line;
while ((line = bufferedReader.readLine()) != null)
{
content.append(line + "\n");
}
bufferedReader.close();
}
catch(Exception e)
{
e.printStackTrace();
}
return content.toString();
}
}
}
You can call seismic_text.getUrlContents(url); but it will cause NetworkOnMainThreadException
Just wrap this call to Simple AsynkTask.
class MyTask extends AsyncTask<Void, Void, String> {
#Override
protected String doInBackground(Void... params) {
try {
return seismic_text.getUrlContents(url);
} catch (InterruptedException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
// TODO handle result here
}
}
And call it from your code:
new MyTask().execute();
Simply call this in your MainActivty.java:
seismic_text.getUrlContents(url);
I have a button that gets month and year from spinners then calls an Async task, which read json data. That part works fine But if I try and change the month and year then click the button again it does nothing. I have to press back to reload the page to click the button again to get different results.
Here is my code. Can any of you smart folks please help me.
package com.app.simplictyPortal;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.app.simplicityPortal.adapter.InvoiceAdapter;
import android.app.Fragment;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Spinner;
public class InvoiceFragment extends Fragment {
public InvoiceFragment(){}
Button load;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_invoice, container, false);
ArrayList<String> years = new ArrayList<String>();
int thisYear = Calendar.getInstance().get(Calendar.YEAR);
int currentMonth = Calendar.getInstance().get(Calendar.MONTH);
for (int i = 2013; i <= thisYear; i++)
{
years.add(Integer.toString(i));
}
//String tmonth = Integer.toString(currentMonth);
String tyear = Integer.toString(thisYear);
final Spinner year = (Spinner)rootView.findViewById(R.id.spinner1);
final Spinner month = (Spinner)rootView.findViewById(R.id.spinner2);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(),
android.R.layout.simple_spinner_item, years);
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
year.setAdapter(adapter);
year.setSelection(adapter.getPosition(tyear));
ArrayAdapter<CharSequence> adapter2 = ArrayAdapter.createFromResource(getActivity(),
R.array.month, android.R.layout.simple_spinner_item);
// Specify the layout to use when the list of choices appears
adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
month.setAdapter(adapter2);
month.setSelection(currentMonth);
load=(Button)rootView.findViewById(R.id.button1);
load.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
String y = (String) year.getSelectedItem();
int im = month.getSelectedItemPosition();
String m = Integer.toString(im +1);
final GlobalClass globalVariable = (GlobalClass) getActivity().getApplicationContext();
final String Compid = globalVariable.getCompid();
new InvoiceAsyncTask().execute("http://dev-sql1:8080/api/invoice/getall/"+Compid+"?m="+m+"&y="+y);
}
});
return rootView;
}
public void invoice(JSONArray jArray) {
ListView lv = (ListView) getView().findViewById(R.id.listView1);
List<ListViewItem> items = new ArrayList<InvoiceFragment.ListViewItem>();
try {
for (int i = 0; i <jArray.length(); i++) {
final JSONObject json_data = jArray.getJSONObject(i);
items.add(new ListViewItem()
{{
Vendor= json_data.optString("CarrierName");
Bill = "$ " + json_data.optString("BillAmount");
Serviceacct = json_data.optString("ServiceAccountNumber");
Date = json_data.optString("ReceivedDate");
}});
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
InvoiceAdapter adapter = new InvoiceAdapter(getActivity(), items);
lv.setAdapter(adapter);
// TODO Auto-generated method stub
}
public class ListViewItem
{
public String Vendor;
public String Bill;
public String Serviceacct;
public String Date;
} public static String GET(String url){
InputStream inputStream = null;
String result = "";
try {
// create HttpClient
HttpClient httpclient = new DefaultHttpClient();
// make GET request to the given URL
HttpResponse httpResponse = httpclient.execute(new HttpGet(url));
// receive response as inputStream
inputStream = httpResponse.getEntity().getContent();
// convert inputstream to string
if(inputStream != null)
result = convertInputStreamToString(inputStream);
else
result = "Did not work!";
} catch (Exception e) {
Log.d("InputStream", e.getLocalizedMessage());
}
return result;
}
private static String convertInputStreamToString(InputStream inputStream) throws IOException{
BufferedReader bufferedReader = new BufferedReader( new InputStreamReader(inputStream));
String line = "";
String result = "";
while((line = bufferedReader.readLine()) != null)
result += line;
inputStream.close();
return result;
}
public class InvoiceAsyncTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... urls) {
return GET(urls[0]);
}
// onPostExecute displays the results of the AsyncTask.
#Override
protected void onPostExecute(String result) {
try {
JSONArray jArray = new JSONArray(result);
invoice(jArray);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
How do you process results of your InvoiceAsyncTask? Do you implement a callback from your AsyncTask's onPostExecute() to the activity?
Maybe the sample below will help you.
First, implement AsyncTask class with callback interface:
public class ServerRequestAsyncTask extends AsyncTask<String, Void, ServerResponseDetails> {
public ServerRequestAsyncTask(Fragment fragment, ServerRequestDetails request) {
mFragment = fragment;
mRequest = request;
}
public interface OnServerRequestAsyncTaskCompletedListener {
void onServerRequestAsyncTaskCompleted(ServerResponseDetails response);
}
public void cancel() {
if (mHttpGet != null && !mHttpGet.isAborted()) mHttpGet.abort();
cancel(true);
}
And also add onPostExecute():
#Override
protected void onPostExecute(ServerResponseDetails response) {
if (mFragment != null) mFragment.onServerRequestAsyncTaskCompleted(response);
}
I call AsyncTask from Fragment, but you can use it with Activity instead.
Then, in your Activity you implement interface:
#Override
public void onServerRequestAsyncTaskCompleted(ServerResponseDetails response) {
// do what you need here, then 'finish' task by setting mServerRequest to null
mServerRequest = null;
}
And to execute AsyncTask:
protected ServerRequestAsyncTask mServerRequest = null;
public boolean isServerRequestRunning() {
return (mServerRequest != null);
}
public void cancelServerRequest() {
mServerRequest.cancel();
}
public void sendServerRequest(Fragment fragment, ServerRequestDetails request) {
if (Application.isNetworkAvailable()) {
if (!isServerRequestRunning()) {
mServerRequest = new ServerRequestAsyncTask(fragment, request);
mServerRequest.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,
{params});
}
}
}
mServerRequest variable holds reference to currently executed task. You can call mServerRequest.cancel() if need to abort.
Thanks Everyone But I have figured it out. I needed to cancel the Async task in the post execute method.
#Override
protected void onPostExecute(String result) {
try {
JSONArray jArray = new JSONArray(result);
invoice(jArray);
cancel(true);
isCancelled();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}