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Hi I'm beginner to android, I do not know very well used to asychtask but after that I realized I proceeded as am, application forced stoped and error in log FATAL EXCEPTION: AsyncTask #1 , thanks for help i need to extract the contents of a mysql database on a listview
package com.example.test;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URI;
import java.util.ArrayList;
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 android.app.Activity;
import android.content.Intent;
import android.content.res.Resources;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.StrictMode;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class Actu_Connextion extends Activity {
Actualite oActualite;
ArrayList<Actualite> listeActualites;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.acutalite_main);
int actionBarTitleId = Resources.getSystem().getIdentifier("action_bar_title", "id", "android");
TextView actionBarTextView = (TextView)findViewById(actionBarTitleId);
actionBarTextView.setTextColor(Color.WHITE);
this.listeActualites = new ArrayList<Actualite>();
new DownloadTask().execute();
}
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.refresh, menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item){ // Quand on appuis sur l/'item
switch (item.getItemId()){
case R.id.refresh: // selectionne l'item par id
return true;
case R.id.back_menu_principale: // selectionne l'item par id
Intent intent = new Intent(getBaseContext() ,MainActivity.class);
startActivity(intent);
default:
return super.onOptionsItemSelected(item);
}
}
public class DownloadTask extends AsyncTask<String, Integer, ArrayList<Actualite>>{
ArrayList<Actualite> listeActualites;
// Invoked by execute() method of this object
#Override
protected ArrayList<Actualite> doInBackground(String... jsonData) {
StringBuffer stringB = new StringBuffer("");
BufferedReader bufR = null;
try{
HttpClient client = new DefaultHttpClient();
HttpGet requete = new HttpGet();
URI uri = new URI("http://192.168.1.3/actu.php");
requete.setURI(uri);
HttpResponse reponse = client.execute(requete);
InputStream is = reponse.getEntity().getContent();
bufR = new BufferedReader(new InputStreamReader(is));
String ligneLue = bufR.readLine();
while(ligneLue != null){
stringB.append(ligneLue);
stringB.append("\n");
ligneLue = bufR.readLine();
}
}catch(Exception e){
e.printStackTrace();
}finally{
if(bufR != null){
try{
bufR.close();
}catch(IOException ioe){
ioe.printStackTrace();
}
}
}
try{
JSONArray jArray = new JSONArray(stringB.toString());
for(int i = 0; i<jArray.length(); i++){
oActualite = new Actualite();
oActualite.setoContenu(jArray.getJSONObject(i).getString("contenu").toString());
oActualite.setoChemin(jArray.getJSONObject(i).getString("chemin").toString());
oActualite.setoDate(jArray.getJSONObject(i).getString("date").toString());
this.listeActualites.add(oActualite);
}
}catch(JSONException jex){
jex.printStackTrace();
}
return listeActualites;
}
// Executed after the complete execution of doInBackground() method
#Override
protected void onPostExecute(ArrayList<Actualite> listeActualites){
ActualiteAdapter adapter = new ActualiteAdapter(Actu_Connextion.this, listeActualites);
ListView listeVueActualites = (ListView) findViewById(R.id.lstActualites);
listeVueActualites.setAdapter(adapter);
}
}
}
I think you might be calling add on a null object...that is here:
this.listeActualites.add(oActualite);
where listeActualites is referring to the local member of AsyncTask and you're never initializing it.
Related
in my application i am fetching json data from online server. and after that i am trying to display the data by toast. but the application stop working. if i commented the toast section then the application runs smoothly. so i think there is a problem in toast section. so guys plz help me to find out the reason for the problem
package com.example.getdata;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import android.app.Activity;
public class MainActivity extends Activity {
EditText password,username;
String pass,user;
//TextView output;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void onConnect(View v) {
new Thread(){
public void run(){
HttpClient myClient = new DefaultHttpClient();
HttpPost post = new HttpPost("http://tusharinfotech.com/debasish/get_data.php");
try {
List<NameValuePair> myArgs = new ArrayList<NameValuePair>();
// myArgs.add(new BasicNameValuePair("username", user));
// myArgs.add(new BasicNameValuePair("password", pass));
post.setEntity(new UrlEncodedFormEntity(myArgs));
HttpResponse myResponse = myClient.execute(post);
BufferedReader br = new BufferedReader( new InputStreamReader(myResponse.getEntity().getContent()));
String line = "";
String data1 ="";
while ((line = br.readLine()) != null)
{
try {
JSONArray myarray = new JSONArray(line);
for(int i=0;i<myarray.length();i++){
JSONObject jsonObject = myarray.getJSONObject(i);
int id = Integer.parseInt(jsonObject.optString("FOOD_ID").toString());
String name = jsonObject.optString("FOOD_NAME").toString();
data1 += "Node"+i+" : \n id= "+ id +" \n Name= "+ name +" \n ";
}
//Log.d("mytag",data);
//this application stop working for this toast part.. if i commented it then the application run smoothly
Toast.makeText(getApplicationContext(),data1, Toast.LENGTH_LONG).show();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//EditText output1 = (EditText) findViewById(R.id.editText1);
// output1.setText(data);
Log.d("mytag", line);
}
}
catch (IOException e) {
e.printStackTrace();
}
}
}.start();
}
}
I guess you are trying to show toast on a background thread, which is not allowed in android. you can use this code to show toast in background thread :
activity.runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(getApplicationContext(), "Hello", Toast.LENGTH_SHORT).show();
}
});
You must display Toast only from UI thread, to workaround this you can get use of runOnUiThread() method or create new Handler and pass in constructor Looper.getMainLoopper()
You could use AsyncTask Framework to make background processing easier http://developer.android.com/reference/android/os/AsyncTask.html.
The method onPostExecute(Result) will be run on your UI thread there for you can change your UI element here.
I'm just new to android and java and i m trying to build a sample android application.
I picked up application view from androhive looks like google+ app
and made my function following to many tutorials online
but i'm unable to integrate them.
here are my codes
Here is my fragment sample which is used in switching activity using sidebar
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class MHEFragment extends Fragment {
public MHEFragment(){}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_home, container, false);
return rootView;
}
}
Heres my function os listview
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;
public class MainActivity extends Activity {
public final static String EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE";
private String jsonResult;
private String url = "http://192.168.129.1/1.php";
private ListView listView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listView1);
accessWebService();
}
#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;
}
// Async Task to access the web
private class JsonReadTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... params) {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(params[0]);
try {
HttpResponse response = httpclient.execute(httppost);
jsonResult = inputStreamToString(
response.getEntity().getContent()).toString();
}
catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
private StringBuilder inputStreamToString(InputStream is) {
String rLine = "";
StringBuilder answer = new StringBuilder();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
try {
while ((rLine = rd.readLine()) != null) {
answer.append(rLine);
}
}
catch (IOException e) {
// e.printStackTrace();
Toast.makeText(getApplicationContext(),
"Error..." + e.toString(), Toast.LENGTH_LONG).show();
}
return answer;
}
#Override
protected void onPostExecute(String result) {
ListDrwaer();
}
}// end async task
public void accessWebService() {
JsonReadTask task = new JsonReadTask();
// passes values for the urls string array
task.execute(new String[] { url });
}
// build hash set for list view
public void ListDrwaer() {
List<Map<String, String>> storyList = new ArrayList<Map<String, String>>();
try {
JSONObject jsonResponse = new JSONObject(jsonResult);
JSONArray jsonMainNode = jsonResponse.optJSONArray("story");
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
String name = jsonChildNode.optString("story_name");
String number = jsonChildNode.getString("story_id").toString();
String outPut = number + "-" + name;
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapter, View name, int position,
long number) {
Intent intnt = new Intent(getApplicationContext(), Tester.class);
String deta = adapter.getItemAtPosition(position).toString();
String myStr = deta.replaceAll( "[^\\d]", "" );
intnt.putExtra(EXTRA_MESSAGE,myStr);
startActivity(intnt);
}
});
storyList.add(createStory("stories", outPut));
}
} catch (JSONException e) {
Toast.makeText(getApplicationContext(), "Error" + e.toString(),
Toast.LENGTH_SHORT).show();
}
SimpleAdapter simpleAdapter = new SimpleAdapter(this, storyList,
android.R.layout.simple_list_item_1,
new String[] { "stories" }, new int[] { android.R.id.text1 });
listView.setAdapter(simpleAdapter);
}
private HashMap<String, String> createStory(String name, String number) {
HashMap<String, String> storyNameNo = new HashMap<String, String>();
storyNameNo.put(name, number);
return storyNameNo;
}
}
How can i integrate my listview in above fragment?
If you want ListView in fragment then you'd be better off using your Fragment which would subclass ListFragment.
And the onCreateView() from ListFragment will return a ListView that you can populate.
http://developer.android.com/reference/android/app/ListFragment.html
http://www.vogella.com/tutorials/AndroidListView/article.html#listfragments
For Fragments, if you want a separate ListView and more in one fragment, it'l help if you go through:
http://www.easyinfogeek.com/2013/07/full-example-of-using-fragment-in.html
..for what is more to the layout and calling onCreateView()
Also, (not a part of the question, but from & for your code) if it helps, i'd suggest
Use a for each loop where you can instead of for(;;)
(in your case at: for each json child node in json main node)
http://docs.oracle.com/javase/1.5.0/docs/guide/language/foreach.html
How does the Java 'for each' loop work?
I have a feature in my app that gets a users gps coordinates then returns nearby breweries. When I use the feature it has never forced closed, and others have tested it to and it worked. One user reported this error when they opened the activity that gets the user location and tries to get the location of breweries:
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.beerportfolio.beerportfoliopro/com.example.beerportfoliopro.FindBrewery}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2355)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2391)
at android.app.ActivityThread.access$600(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1335)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:155)
at android.app.ActivityThread.main(ActivityThread.java:5511)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1029)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:796)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.example.beerportfoliopro.FindBrewery.onCreate(FindBrewery.java:42)
at android.app.Activity.performCreate(Activity.java:5066)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1101)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2311)
... 11 more
My activity that is launched is:
package com.example.beerportfoliopro;
import android.content.Context;
import android.content.SharedPreferences;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.util.Log;
import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;
import com.beerportfolio.beerportfoliopro.R;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
/**
* Created by mike on 7/3/13.
*/
public class FindBrewery extends ActionbarMenu {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.beer_location_list);
String title = "Nearby Breweries";
TextView topTitle = (TextView) findViewById(R.id.beerLocationTitle);
topTitle.setText(title);
//get user location
LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
double longitude = location.getLongitude();
double latitude = location.getLatitude();
//construct url
String url = myURLandKey;
Log.d("urlTest",url);
//async task goes here
new GetNearbyBreweries(this).execute(url);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main2, menu);
return true;
}
}
Lastly my asynctask is:
package com.example.beerportfoliopro;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
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.JSONObject;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.preference.PreferenceManager;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;
import com.beerportfolio.beerportfoliopro.R;
public class GetNearbyBreweries extends AsyncTask
<String, Void, String> {
Context c;
private ProgressDialog Dialog;
public GetNearbyBreweries (Context context)
{
c = context;
Dialog = new ProgressDialog(c);
}
#Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
return readJSONFeed(arg0[0]);
}
protected void onPreExecute() {
Dialog.setMessage("Locating Breweries");
Dialog.setTitle("Loading");
Dialog.setCancelable(false);
Dialog.show();
}
protected void onPostExecute(String result){
//decode json here
try{
JSONObject json = new JSONObject(result);
//acces listview
ListView lv = (ListView) ((Activity) c).findViewById(R.id.locationList);
//make array list for beer
final List<BreweryLocationData> tasteList = new ArrayList<BreweryLocationData>();
for(int i = 0; i < json.getJSONArray("data").length(); i++) {
String brewery = json.getJSONArray("data").getJSONObject(i).getJSONObject("brewery").getString("name");
String id = json.getJSONArray("data").getJSONObject(i).getJSONObject("brewery").getString("id");
String latitude = json.getJSONArray("data").getJSONObject(i).getString("latitude");
String longitude = json.getJSONArray("data").getJSONObject(i).getString("longitude");
String distance = json.getJSONArray("data").getJSONObject(i).getString("distance");
int count = i + 1;
//create object
BreweryLocationData tempLocation = new BreweryLocationData(brewery, id, longitude , latitude,distance);
//add to arraylist
tasteList.add(tempLocation);
//add items to listview
BreweryLocationInfoAdapter adapter1 = new BreweryLocationInfoAdapter(c ,R.layout.listview_item_row, tasteList);
lv.setAdapter(adapter1);
//set up clicks
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1,
int arg2, long arg3) {
BreweryLocationData o=(BreweryLocationData)arg0.getItemAtPosition(arg2);
String tempID = o.id;
Toast toast = Toast.makeText(c, tempID, Toast.LENGTH_SHORT);
toast.show();
//get beer details from id
Intent myIntent = new Intent(c, BreweryPage2.class);
myIntent.putExtra("id", tempID);
c.startActivity(myIntent);
}
});
}
}
catch(Exception e){
}
Dialog.dismiss();
}
public String readJSONFeed(String URL) {
StringBuilder stringBuilder = new StringBuilder();
HttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(URL);
try {
HttpResponse response = httpClient.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) {
HttpEntity entity = response.getEntity();
InputStream inputStream = entity.getContent();
BufferedReader reader = new BufferedReader(
new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
stringBuilder.append(line);
}
inputStream.close();
} else {
Log.d("JSON", "Failed to download file");
}
} catch (Exception e) {
Log.d("readJSONFeed", e.getLocalizedMessage());
}
return stringBuilder.toString();
}
}
You are getting a force close when attempting to get the users location. I would add validation that the use has GPS enabled and if not then give them an alert dialog asking them to enable, you may also send them directly to GPS settings.
Can the user reproduce the error?
From your code listing it seems line 42 is(maybe you edited it though):
39 LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
40 Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
41 double longitude = location.getLongitude();
42 double latitude = location.getLatitude();
Cant see why getLatitude() would break and not getLongitude()
You should validate location, to make sure you have it.
As a couple of others have pointed out, it is telling you that the error is on line 42. Unfortunately you have slightly affected the line numbers pasting it here. On your line 42 you are assuming something is not null, and it actually is null.
Given that LocationManager#getLastKnownLocation can return null, and you're not checking for that, I'd say that was your issue, and that your line 42 is where you call location.getLongitude().
getLastKnownLocation will only return a Location if the provider you specify has been used recently. If nothing has forced it to find a location yet, or for a long time (Android considers the last location too old to be correct), then you will get null.
I'm trying to develop a simple app that gets data from web service and displays it
It throws exception exactly when he calls response.execute(client)
package com.example.webbasedapp;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URI;
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 android.util.Log;
public class GETMethods {
public String getInternetData() throws Exception{
BufferedReader in=null;
String Data=null;
try{
HttpClient client=new DefaultHttpClient();
URI web=new URI("http://www.mybringback.com/");
HttpGet request = new HttpGet();
request.setURI(web);
HttpResponse reponse=client.execute(request);
Log.v("response code", reponse.getStatusLine()
.getStatusCode() + "");
InputStream inp=reponse.getEntity().getContent();
in=new BufferedReader(new InputStreamReader(inp));
StringBuffer buf=new StringBuffer();
String l="";
String nl=System.getProperty("line.separator");
while((l=in.readLine())!=null){
buf.append(l+nl);
}
in.close();
Data=buf.toString();
return Data;
}finally{
if(in!=null){
try{
in.close();
return Data;
}catch (Exception e){
Log.d("error",e.toString());
}
}
}
}
}
And this is my main activity
package com.example.webbasedapp;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;
public class Home extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
TextView test = (TextView) findViewById(R.id.data);
GETMethods data = new GETMethods();
String d = null;
try {
d = data.getInternetData();
// test.setText(d);
} catch (Exception e) {
// TODO Auto-generated catch block
d = "bla";
Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
// Log.d("testW",e.getMessage());
}
test.setText(d);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.home, menu);
return true;
}
}
You are attempting to access the network on the UI thread which is not allowed due to potential hangup issues. Look into AysncTask and implement GETMethods as one of them. It will look something like this:
public class GETMethods extends AsyncTask<String, Void, String>{
protected void doInBackground(String... params){
YourNetworkCode
}
}
So I am trying to create an Android app which basically reads out the twitter feed according to the search query inside a UI. The feed that I need to display form the parsed JSON is the user name, handle, profile picture and the tweet.
Now I have created the whole thing and my code compiles but as soon as I run it the app opens and I write something in the search feed and hit enter - " Unfortunately, AppName has stopped working " I am attaching my logcat and my source code for reference.
*Solved the issue by removing set text from DoInBackground and then giving adequate permission for Android to access internet. The issue now is that as I try and display the profile picture, the URL gets displayed, not the image.
Source code :
package com.example.twittersearchactivity;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
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.JSONObject;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class TwitterSearchActivity extends Activity {
private TextView tweetDisplay;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_twitter_search);
tweetDisplay = (TextView)findViewById(R.id.tweet_txt);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.twitter_search, menu);
return true;
}
public void searchTwitter(View view){
EditText searchTxt = (EditText)findViewById(R.id.search_edit);
String searchTerm = searchTxt.getText().toString();
if(searchTerm.length()>0){
try{
String encodedSearch = URLEncoder.encode(searchTerm, "UTF-8");
String searchURL = "http://search.twitter.com/search.json?q="+encodedSearch;
new GetTweets().execute(searchURL);
Log.i("1", "entered the searchterm");
}
catch(Exception e){
tweetDisplay.setText("Whoops - something went wrong!");
e.printStackTrace();
}
}
else
tweetDisplay.setText("Enter a search query!");
}
private class GetTweets extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... twitterURL) {
StringBuilder tweetFeedBuilder = new StringBuilder();
for (String searchURL : twitterURL) {
HttpClient tweetClient = new DefaultHttpClient();
try {
HttpGet tweetGet = new HttpGet(searchURL);
HttpResponse tweetResponse = tweetClient.execute(tweetGet);
StatusLine searchStatus = tweetResponse.getStatusLine();
if (searchStatus.getStatusCode() == 200) {
HttpEntity tweetEntity = tweetResponse.getEntity();
Log.i("2", "entered gettweets");
InputStream tweetContent = tweetEntity.getContent();
InputStreamReader tweetInput = new InputStreamReader(tweetContent);
BufferedReader tweetReader = new BufferedReader(tweetInput);
String lineIn;
while ((lineIn = tweetReader.readLine()) != null) {
tweetFeedBuilder.append(lineIn);
Log.i("3", "entered while in dobackground");
}
}
else {Log.i("error", "error");}
//tweetDisplay.setText("Whoops - something went wrong!");
}
catch(Exception e) {
Log.e("DEBUGTAG", "Remote Image Exception", e);
//tweetDisplay.setText("Whoops - something went wrong!");
e.printStackTrace();
}}
return tweetFeedBuilder.toString();
}
protected void onPostExecute(String result) {
StringBuilder y;
StringBuilder tweetResultBuilder = new StringBuilder();
try {
Log.i("tag", "entered try block");
JSONObject resultObject = new JSONObject(result);
JSONArray tweetArray = resultObject.getJSONArray("results");
for (int t=0; t<tweetArray.length(); t++) {
Log.i("tag", "entered the json stream");
JSONObject tweetObject = tweetArray.getJSONObject(t);
tweetResultBuilder.append(tweetObject.getString("from_user")+": ");
tweetResultBuilder.append(tweetObject.getString("from_user_name")+": ");
tweetResultBuilder.append(tweetObject.get("text")+"\n\n");
String imageURL = (String) tweetObject.get(("profile_image_url")+": ");
Bitmap bitmap = BitmapFactory.decodeStream((InputStream)new URL(imageURL).getContent());
#SuppressWarnings("deprecation")
Drawable d =new BitmapDrawable(bitmap);
d.setAlpha(255);
TextView.setCompoundDrawablesWithIntrinsicBounds(0,0,1,0);
}
}
catch (Exception e) {
tweetDisplay.setText("Whoops - something went wrong!");
e.printStackTrace();}
if(tweetResultBuilder.length()>0)
tweetDisplay.setText(tweetResultBuilder.toString());
else
tweetDisplay.setText("Sorry - no tweets found for your search!");
}
}}
You can't call view functions like setText on another thread like an AsyncTask doInBackground function. You need to do it in onPostExecute.