Develop Reference

Android get attribute value from xml

I am trying to make an app which uses last.fm's web API, sends a query for similar artists and returns all the names of the similar artists. It seems as though I manage to connect and get the xml response properly. However, I cannot extract the value of the name-attribute. I am using artistName = xmlData.getAttributeValue(null, "name"); but all it gives me is null.
import android.app.Activity;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;
import java.util.*;
#SuppressWarnings("FieldCanBeLocal")
public class MainActivity extends Activity implements Observer {
private final String INPUTERROR = "Invalid/missing artist name.";
private NetworkCommunication nc;
private ArrayList<String> list;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
nc = new NetworkCommunication();
nc.register(this);
list = new ArrayList<>();
ListView lv = (ListView)findViewById(R.id.ListView_similarArtistsList);
ArrayAdapter adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, list);
lv.setAdapter(adapter);
}
public void searchButton_Clicked(View v){
EditText inputField = (EditText)findViewById(R.id.editText_artistName);
String searchString = inputField.getText().toString();
searchString = cleanSearchString(searchString);
if(validateSearchString(searchString)){
nc.setSearchString(searchString);
nc.execute();
}
else{
Toast.makeText(MainActivity.this, INPUTERROR, Toast.LENGTH_SHORT).show();
}
}
private String cleanSearchString(String oldSearchString){
String newString = oldSearchString.trim();
newString = newString.replace(" ", "");
return newString;
}
private boolean validateSearchString(String searchString){
boolean rValue = true;
if(TextUtils.isEmpty(searchString)){
rValue = false;
}
return rValue;
}
#Override
public void update(String artistName) {
list.add(artistName);
}
}
Here is my Network Communications class:
import android.os.AsyncTask;
import android.util.Log;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
#SuppressWarnings("FieldCanBeLocal")
class NetworkCommunication extends AsyncTask<Object, String, Integer> implements Subject {
private final String MYAPIKEY = "--------------------------";
private final String ROOT = "http://ws.audioscrobbler.com/2.0/";
private final String METHOD = "?method=artist.getsimilar";
private ArrayList<Observer> observers;
private int amountOfArtists = 0;
private String foundArtistName;
private String searchString;
NetworkCommunication(){
observers = new ArrayList<>();
}
void setSearchString(String newSearchString){
searchString = newSearchString;
}
private XmlPullParser sendRequest(){
try{
URL url = new URL(ROOT + METHOD + "&artist=" + searchString + "&api_key=" + MYAPIKEY);
XmlPullParser receivedData = XmlPullParserFactory.newInstance().newPullParser();
receivedData.setInput(url.openStream(), null);
return receivedData;
}
catch (IOException | XmlPullParserException e){
Log.e("ERROR", e.getMessage(), e);
}
return null;
}
private int tryProcessData(XmlPullParser xmlData){
int artistsFound = 0;
String artistName;
int eventType;
try{
while ((eventType = xmlData.next()) != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_TAG) {
if(xmlData.getName().equals("name")){
artistName = xmlData.getAttributeValue(null, "name");
publishProgress(artistName);
artistsFound++;
}
}
}
}
catch (IOException | XmlPullParserException e){
Log.e("ERROR", e.getMessage(), e);
}
if (artistsFound == 0) {
publishProgress();
}
return artistsFound;
}
#Override
protected Integer doInBackground(Object... params) {
XmlPullParser data = sendRequest();
if(data != null){
return tryProcessData(data);
}
else{
return null;
}
}
#Override
protected void onProgressUpdate(String... values){
/*
if (values.length == 0) {
//No data found...
}
*/
if (values.length == 1) {
setFoundArtistName(values[0]);
notifyObserver();
}
super.onProgressUpdate(values);
}
private void setFoundArtistName(String newArtistName){
foundArtistName = newArtistName;
}
#Override
public void register(Observer newObserver) {
observers.add(newObserver);
}
#Override
public void unregister(Observer deleteObserver) {
observers.remove(deleteObserver);
}
#Override
public void notifyObserver() {
for (Observer o : observers) {
Log.i("my tag.... ", "name = " + foundArtistName);
o.update(foundArtistName);
}
}
}
Here's a screenshot of the xml response in Google Chrome:
The only thing I am interested in extracting at this moment is the the value of the Name-Element.
I am logging the value of foundArtistName (in the method notifyObserver) it gives me A LOT of "my tag.... name = null my tag.... name = null my tag.... name = null etc.."
EDIT: I tried using getText() instead of getAttributeValue(), but it also gives me null.

I found the solution. I was using: artistName = xmlData.getAttributeValue(null, "name");, when I really should've used: artistName = xmlData.nextText();

My list is loading again when I am Pressing Back Button

I am also getting ArrayListIndexOutofBound when I am pressing list item when the orientation is changed.As far my knowledge of android I have written Parcelable code correctly.But I think my issues are with the recycler view setup.I am confused with two declaration of my adapter.Help me
MainActivity.class
package com.reader.ashishyadav271.hackernewsmaterial;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteStatement;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Parcelable;
import android.os.PersistableBundle;
import android.support.v4.util.LruCache;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ListView;
import android.widget.Toast;
import com.wang.avi.AVLoadingIndicatorView;
import org.json.JSONArray;
import org.json.JSONObject;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class MainActivity extends AppCompatActivity implements MyCustomAdapter.ClickListener {
private static final String STATE_LIST = "state_list";
Map<Integer, String> articleURLs = new HashMap<>();
Map<Integer, String> articleTitles = new HashMap<>();
Map<Integer, String> articleDates =new HashMap<>();
Map<Integer, String> articleAuthors =new HashMap<>();
ArrayList<Integer> articleIds=new ArrayList<>();
SQLiteDatabase articlesDB;
ArrayList<Information> data=new ArrayList<>();
ArrayList<String> titles=new ArrayList<>();
ArrayList<String> urls=new ArrayList<>();
ArrayList<String> authors=new ArrayList<>();
ArrayList<String> dateAndTimes=new ArrayList<>();
MyCustomAdapter adapter;
RecyclerView recyclerView;
AVLoadingIndicatorView av;
List<DownloadTask> tasks;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
av= (AVLoadingIndicatorView) findViewById(R.id.avloadingIndicatorView);
av.setVisibility(View.INVISIBLE);
tasks = new ArrayList<>();
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
recyclerView= (RecyclerView) findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
recyclerView.addItemDecoration(new SimpleDividerItemDecoration(
getApplicationContext()
));
articlesDB = this.openOrCreateDatabase("Articles", MODE_PRIVATE, null);
articlesDB.execSQL("CREATE TABLE IF NOT EXISTS article (id INTEGER PRIMARY KEY," +
" articleId INTEGER," +
" url VARCHAR," +
" title VARCHAR," +
" author VARCHAR," +
" date VARCHAR)");
if(savedInstanceState != null) {
data=savedInstanceState.getParcelableArrayList(STATE_LIST);
adapter=new MyCustomAdapter(getApplicationContext(),data);
adapter.setClickListener(this);
recyclerView.setAdapter(adapter);
}else{
if (isOnline()) {
requestData("https://hacker-news.firebaseio.com/v0/topstories.json?print=pretty");
} else {
updateDisplay();
Toast.makeText(this, "Network isn't available", Toast.LENGTH_LONG).show();
}
}
//adapter=new MyCustomAdapter(getApplicationContext(),getData());
//adapter.setClickListener(this);
//recyclerView.setAdapter(adapter);
}
protected boolean isOnline() {
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
if (netInfo != null && netInfo.isConnectedOrConnecting()) {
return true;
} else {
return false;
}
}
private void requestData(String uri) {
DownloadTask task = new DownloadTask();
task.execute(uri);
}
#Override
public void itemClicked(View view, int position) {
Intent i = new Intent(getApplicationContext(), Main2Activity.class);
i.putExtra("articleUrl", urls.get(position));
startActivity(i);
}
protected void updateDisplay() {
adapter=new MyCustomAdapter(getApplicationContext(),getData());
adapter.setClickListener(this);
recyclerView.setAdapter(adapter);;
}
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putParcelableArrayList(STATE_LIST, data);
}
public class DownloadTask extends AsyncTask<String, Void, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
if (tasks.size() == 0) {
av.setVisibility(View.VISIBLE);
}
tasks.add(this);
}
#Override
protected String doInBackground(String... urls) {
String result = "";
URL url;
HttpURLConnection urlConnection;
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;
result += current;
data = reader.read();
}
JSONArray jsonArray = new JSONArray(result);
articlesDB.execSQL("DELETE FROM article");
for (int i = 0; i < 15; i++) {
String articleId = jsonArray.getString(i);
url = new URL("https://hacker-news.firebaseio.com/v0/item/" + articleId + ".json?print=pretty");
urlConnection = (HttpURLConnection) url.openConnection();
in = urlConnection.getInputStream();
reader = new InputStreamReader(in);
data = reader.read();
String articleInfo = "";
while (data != -1 ) {
char current = (char) data;
articleInfo += current;
data = reader.read();
}
JSONObject jsonObject = new JSONObject(articleInfo);
String articleTitle = jsonObject.getString("title");
String articleURL = jsonObject.getString("url");
String articleDate=jsonObject.getString("time");
String articleAuthor=jsonObject.getString("by");
long unixSeconds = Long.valueOf(articleDate);
Date date = new Date(unixSeconds*1000L); // *1000 is to convert seconds to milliseconds
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss"); // the format of your date
String formattedarticleDate = sdf.format(date);
articleIds.add(Integer.valueOf(articleId));
articleTitles.put(Integer.valueOf(articleId), articleTitle);
articleURLs.put(Integer.valueOf(articleId), articleURL);
articleDates.put(Integer.valueOf(articleId), formattedarticleDate);
articleAuthors.put(Integer.valueOf(articleId), articleAuthor);
String sql = "INSERT INTO article (articleId, url, title, author, date) VALUES (? , ? , ? , ?, ?)";
SQLiteStatement statement = articlesDB.compileStatement(sql);
statement.bindString(1, articleId);
statement.bindString(2, articleURL);
statement.bindString(3, articleTitle);
statement.bindString(4, articleAuthor);
statement.bindString(5, formattedarticleDate);
statement.execute();
}
}catch (Exception e) {
e.printStackTrace();
}
return result;
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
tasks.remove(this);
if (tasks.size() == 0) {
av.setVisibility(View.INVISIBLE);
}
updateDisplay();
}
}
private List<Information> getData() {
/*List<Information> data=new ArrayList<>();
for(int i=0;i<20;i++){
titles.add(i,"Wikileaks Asssange wins UN ruling on arbitrary detention");
url.add(i,"https://www.google.co.in/search?q=best+custom+list+row");
date.add(i,"3 hrs");
author.add(i,"aburan28");
}
for(int i=0;i<20;i++){
Information current=new Information();
current.title=titles.get(i);
current.url=url.get(i);
current.author=author.get(i);
current.date=date.get(i);
data.add(current);
}
return data;*/
Cursor c = articlesDB.rawQuery("SELECT * FROM article", null);
try {
int urlIndex = c.getColumnIndex("url");
int titleIndex = c.getColumnIndex("title");
int authorIndex = c.getColumnIndex("author");
int dateIndex = c.getColumnIndex("date");
c.moveToFirst();
titles.clear();
//urls.clear();
authors.clear();
dateAndTimes.clear();
int i=0;
while (c != null) {
titles.add(c.getString(titleIndex));
urls.add(c.getString(urlIndex));
authors.add(c.getString(authorIndex));
dateAndTimes.add(c.getString(dateIndex));
Information current=new Information();
current.title=titles.get(i);
current.url=urls.get(i);
current.author=authors.get(i);
current.date = dateAndTimes.get(i);
data.add(current);
i++;
c.moveToNext();
}
}catch (Exception e) {
e.printStackTrace();
}finally {
c.close();
}
return data;
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
startActivity(new Intent(getApplicationContext(),SettingsActivity.class));
return true;
}
if (id == R.id.action_about) {
startActivity(new Intent(getApplicationContext(),About.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
Information.class
package com.reader.ashishyadav271.hackernewsmaterial;
import android.os.Parcel;
import android.os.Parcelable;
public class Information implements Parcelable {
public String title;
public String author;
public String date;
public String url;
public Information(){
}
protected Information(Parcel in) {
title = in.readString();
author = in.readString();
date = in.readString();
url = in.readString();
}
public static final Creator<Information> CREATOR = new Creator<Information>() {
#Override
public Information createFromParcel(Parcel in) {
return new Information(in);
}
#Override
public Information[] newArray(int size) {
return new Information[size];
}
};
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(title);
dest.writeString(author);
dest.writeString(date);
dest.writeString(url);
}
}
Log Cat Error
02-06 14:52:58.106 8369-8369/com.reader.ashishyadav271.hackernewsmaterial E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.reader.ashishyadav271.hackernewsmaterial, PID: 8369
java.lang.IndexOutOfBoundsException: Invalid index 0, size is 0
at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
at java.util.ArrayList.get(ArrayList.java:308)
at com.reader.ashishyadav271.hackernewsmaterial.MainActivity.itemClicked(MainActivity.java:137)
at com.reader.ashishyadav271.hackernewsmaterial.MyCustomAdapter$MyViewHolder.onClick(MyCustomAdapter.java:77)
at android.view.View.performClick(View.java:4471)
at android.view.View$PerformClick.run(View.java:18778)
at android.os.Handler.handleCallback(Handler.java:808)
at android.os.Handler.dispatchMessage(Handler.java:103)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:5345)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:828)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:644)
at dalvik.system.NativeStart.main(Native Method)

Now I get it after years.I would have simply used.
FLAG_ACTIVITY_CLEAR_TOP - If set, and the activity being launched is already running in the current task, then instead of launching a new instance of that activity, all of the other activities on top of it will be closed and this Intent will be delivered to the (now on top) old activity as a new Intent.

Can not see progress on Progress bar in Android

On button click I am calling openChannel function
fetchXML is a thread which downloads xml and sets variables. Though it takes 2-5 seconds to load new view I can see progressbar jump from 0 to 100 directly.
Also Toast in openchannel ... it loads only after new view is loaded i.e. after loadView ... which breaks the purpose for what it was written.
Toast should run before showNews() but it is getting executed after it !!!!
Why it is getting delayed ?
Any help aprreciated.
UPDATE :
HandleXML.java
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;
public class HandleXML
{
private List<String> title = new ArrayList<String>();
private List<String> description = new ArrayList<String>();
private int totalNews = 0;
private String urlString = null;
private XmlPullParserFactory xmlFactoryObject = null;
public volatile boolean parsingComplete = true;
public HandleXML(String url)
{
this.urlString = url;
}
public List<String> getTitle()
{
return title;
}
public List<String> getDescription()
{
return description;
}
public int getTotalNews()
{
return totalNews;
}
public void parseXMLAndStoreIt(XmlPullParser myParser)
{
int event;
String text=null;
boolean isItem = false, isTitle = false;
try
{
event = myParser.getEventType();
while (event != XmlPullParser.END_DOCUMENT && totalNews < 10)
{
String name=myParser.getName();
switch (event)
{
case XmlPullParser.START_TAG:
if(name.equals("item"))
{
isItem = true;
}
break;
case XmlPullParser.TEXT:
text = myParser.getText();
text = text.replaceAll("<.*?>", "");
break;
case XmlPullParser.END_TAG:
if(name.equals("title") && isItem)
{
title.add(text);
isItem = false;
isTitle = true;
}
else if(name.equals("description") && isTitle)
{
description.add(text);
totalNews++;
isTitle = false;
}
break;
}
event = myParser.next();
}
parsingComplete = false;
}
catch (Exception e)
{
e.printStackTrace();
}
}
public void fetchXML()
{
Thread thread = new Thread(new Runnable(){
#Override
public void run()
{
try
{
URL url = new URL(urlString);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.connect();
InputStream stream = conn.getInputStream();
xmlFactoryObject = XmlPullParserFactory.newInstance();
XmlPullParser myparser = xmlFactoryObject.newPullParser();
myparser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false);
myparser.setInput(stream, null);
parseXMLAndStoreIt(myparser);
stream.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
});
thread.start();
}
}
MainActivity.java
import java.util.Date;
import java.util.List;
import java.util.Random;
import android.support.v7.app.ActionBarActivity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.res.Configuration;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.Toast;
public class MainActivity extends ActionBarActivity {
private int titleIds[] = {R.id.news1,R.id.news2,R.id.news3,R.id.news4,R.id.news5,R.id.news6,R.id.news7,R.id.news8,R.id.news9,R.id.news10};
private int descIds[] = {R.id.desc1,R.id.desc2,R.id.desc3,R.id.desc4,R.id.desc5,R.id.desc6,R.id.desc7,R.id.desc8,R.id.desc9,R.id.desc10};
private int colorIds[] = {R.color.DarkSalmon,R.color.DarkCyan,R.color.CornflowerBlue,R.color.BlueViolet,R.color.Goldenrod,R.color.Orchid,R.color.IndianRed,R.color.MediumAquamarine,R.color.LightCoral,R.color.Teal};
private ProgressBar progress;
private HandleXML obj = null;
private int currCnt = 0;
private int rand_color = new Random().nextInt(10);
private int rand_color2 = new Random().nextInt(10);
private boolean inMain = true, inChannel = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
findViewById(R.id.newsScroll).setVisibility(View.GONE);
findViewById(R.id.newsChannels).setVisibility(View.VISIBLE);
progress = (ProgressBar) findViewById(R.id.progressBar);
progress.setMax(100);
}
public void showNews(String url)
{
currDesc = null;
currTitle = null;
obj = null;
progress.setProgress(30);
System.out.println("30 : "+new Date());
rand_color = new Random().nextInt(10);
rand_color2 = new Random().nextInt(10);
if(rand_color == rand_color2 && rand_color == 9)
rand_color2 = 0;
else if(rand_color == rand_color2)
rand_color2 = rand_color+1;
obj = new HandleXML(url);
obj.fetchXML();
progress.setProgress(50);
while(obj.parsingComplete);
progress.setProgress(70);
if(obj.getTitle().size() >0 && obj.getDescription().size() >0)
{
List<String> title = obj.getTitle();
List<String> description = obj.getDescription();
for(int i=0; i<obj.getTotalNews(); i++)
{
Button twT = (Button) findViewById(titleIds[i]);
twT.setText(title.get(i).trim());
twT.setBackground(new ColorDrawable(getResources().getColor(colorIds[rand_color])));
Button twD = (Button) findViewById(descIds[i]);
twD.setText(description.get(i).trim());
twD.setVisibility(View.GONE);
}
}
else
{
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setTitle("AHL NEWS ALERT")
.setMessage("FAILED TO LOAD NEWS !!")
.setCancelable(false)
.setNegativeButton("Close",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
});
AlertDialog alert = builder.create();
alert.show();
}
progress.setProgress(90);
}
public void openChannel(View view)
{
progress.setProgress(10);
Toast.makeText(getBaseContext(), "Loading Please Wait ... ", Toast.LENGTH_SHORT).show();
showNews("http://example.com/news.xml");
progress.setProgress(100);
findViewById(R.id.newsScroll).setVisibility(View.VISIBLE);
findViewById(R.id.newsChannels).setVisibility(View.GONE);
findViewById(R.id.newsScroll).scrollTo(0, 0);
inMain = false;
inChannel = true;
}
}

If fetchXML is using a Thread then that's how it should work. You set the progress to 10 and then call loadNews which calls fetchXML in which there is a Thread.
It takes only a fraction of second to create a Thread for you.
I suggest you use an AsyncTask which give you more control over the process of fetching and parsing the xml. You should update your ProgressBar from inside the AsyncTask. There two method for this. One is onProgressUpdate and the other would be onPostExecute.

Starting new activity through Runnable

I check if a string is NULL in a Thread, if its null, the Handler starts
a Runnable which starts a new Activity.
Everything works fine, but, after the new activity is displayed it switches back to the calling Activity and it crashes.
Here is a code snippet.
if(username==null)
{
dialogs.dismiss();
handlers.post(new MyRunable());
}
and Runnable is
public class MyRunable implements Runnable
{
public void run(){
Toast.makeText(ListActivity.this, "Your Connection is too slow",Toast.LENGTH_LONG).show();
startActivity(new Intent(ListActivity.this,Anim.class));
}
}
Here is my Full Source
package com.cram;
import java.io.File;
import java.io.IOException;
import javax.xml.parsers.ParserConfigurationException;
import org.xml.sax.SAXException;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Typeface;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class BuddyListActivity extends Activity
{
String ss;
private static ProgressDialog dialogs,dialog;
private Thread downloadThreads;
boolean results=false;
Context ctx;
String[]ddd;
ListView lv1;
String [] icons;
BuddyDbAdapter adapter;
NetworkInfo netinfo;
Cursor cursor;
String values;
GetBuddy gb;
BuddyDB db;
String[] username;
String[] firstname;
String[] lastname;
String[] avatar;
String[] id;
File[] iconss;
Handler handlers;
boolean ready=false;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.buddy);
db=new BuddyDB(BuddyListActivity.this);
Typeface font = Typeface.createFromAsset(getAssets(),"fonts/Fortheloveofhate.ttf");
TextView btxt = (TextView) findViewById(R.id.textbuddy);
btxt.setTypeface(font);
ctx=getApplicationContext();
lv1=(ListView)findViewById(R.id.list22);
netinfo=null;
adapter=new BuddyDbAdapter(BuddyListActivity.this);
netinfo=checkDataConnection(getApplicationContext());
handlers = new Handler();
adapter.open();
if(netinfo!=null)
{
downloadThreads = (Thread) getLastNonConfigurationInstance();
if (downloadThreads != null && downloadThreads.isAlive()) {
dialog = ProgressDialog.show(this, "Download", "downloading");
}
startdownload();
}
if(netinfo==null)
{
cursor=adapter.showBuddy();
if (cursor==null||cursor.moveToFirst()==false)
{
AlertDialog.Builder buddybox = new AlertDialog.Builder(this);
buddybox.setMessage("You have No Buddies Yet douche!!");
buddybox.setNeutralButton("Okay", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
startActivity(new Intent(getBaseContext(),Anim.class));
}
});
buddybox.setCancelable(false);
buddybox.show();
}
else
{
cursor.moveToFirst();
int j=0;
ddd=new String[cursor.getCount()];
icons=new String [cursor.getCount()];
do
{
String firstName = cursor.getString(cursor.getColumnIndex(BuddyDbAdapter.BUDDY_FISTNAME));
String lastname = cursor.getString(cursor.getColumnIndex(BuddyDbAdapter.BUDDY_LASTNAME));
String Avatar = cursor.getString(cursor.getColumnIndex(BuddyDbAdapter.AVATAR));
ddd[j]=firstName+" "+lastname;
Log.d("Test", ddd[j]);
icons[j]=Avatar;
Log.d("Test", icons[j]);
j++;
}while(cursor.moveToNext());
iconss= new File[icons.length];
Log.d("Test",icons.length+"");
for (int q = 0; q < icons.length; q++) {
iconss[q] = new File(Download.ROOT +"/"+ icons[q]+".jpg");
Log.d("Test", iconss[q].getAbsolutePath().toString());
}
//adapter.close();
lv1.setAdapter(new BuddyAdapter(BuddyListActivity.this,R.layout.list1,ddd,iconss));
onDestroy();
}
}
}
private void box() {
// TODO Auto-generated method stub
cursor=adapter.showBuddy();
if (cursor==null||cursor.moveToFirst()==false)
{
dialogs.dismiss();
AlertDialog.Builder buddybox = new AlertDialog.Builder(this);
buddybox.setMessage("You have No Buddies Yet ass!!");
buddybox.setNeutralButton("Okay", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
startActivity(new Intent(getBaseContext(),Anim.class));
}
});
buddybox.setCancelable(false);
buddybox.show();
}
}
private NetworkInfo checkDataConnection(Context applicationContext) {
final ConnectivityManager connMgr = (ConnectivityManager)BuddyListActivity.this.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkinfo=null;
final android.net.NetworkInfo wifi =connMgr.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
final android.net.NetworkInfo mobile =connMgr.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if(wifi.isConnected()||mobile.isConnected())
{networkinfo=connMgr.getActiveNetworkInfo();
return networkinfo;
}
else
{
return null;
}
}
#Override
protected void onDestroy() {
super.onDestroy();
if (adapter != null) {
adapter.close();
}
}
#Override
protected void onStop()
{
super.onStop();
finish();
}
private void startdownload() {
dialogs = ProgressDialog.show(BuddyListActivity.this, "Contacting Our Servers", "Geting Your Buddies Avatar");
downloadThreads = new MyThread();
downloadThreads.start();
}
public class MyThread extends Thread {
#Override
public void run() {
try {
new Thread();
GetBuddy tt=new GetBuddy();
String xml=tt.get();
if(xml==null)
{ dialogs.dismiss();
handlers.post(new MyRunable());
ready=false;
//downloadThreads.suspend();
}
final Download cd = new Download();
results = cd.downloadBitmap();
if(results)
{
BuddyParse bp=new BuddyParse();
try {
username=bp.show(xml);
// if(username==null)
// { dialogs.dismiss();
// handlers.post(new MyRunable());
// //downloadThreads.suspend();
// }
firstname=bp.firstname();
lastname=bp.lastname();
avatar=bp.avatar();
id=bp.id();
adapter.deleteAll();
ready=true;
}
catch (ParserConfigurationException e)
{
e.printStackTrace();
}
catch (SAXException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
// Log.d("len", username.length+"");
for(int k=0; k<username.length;k++)
{
adapter.insertBuddy(id[k], username[k], firstname[k], lastname[k], avatar[k]);
Log.d("Test", id[k]+username[k]+firstname[k]+lastname[k]+avatar[k]+"");
}
box();
cursor=adapter.showBuddy();
cursor.moveToFirst();
int i=0;
ddd=new String[cursor.getCount()];
icons=new String [cursor.getCount()];
do
{
String firstName = cursor.getString(cursor.getColumnIndex(BuddyDbAdapter.BUDDY_FISTNAME));
String lastname = cursor.getString(cursor.getColumnIndex(BuddyDbAdapter.BUDDY_LASTNAME));
String Avatar = cursor.getString(cursor.getColumnIndex(BuddyDbAdapter.AVATAR));
ddd[i]=firstName+" "+lastname;
Log.d("Test", ddd[i]);
icons[i]=Avatar;
Log.d("Test",icons[i]);
i++;
}while(cursor.moveToNext());
iconss= new File[avatar.length];
for (int k = 0; k < avatar.length; k++) {
iconss[k] = new File(Download.ROOT+"/"+avatar[k]+".jpg");
Log.d("Test", iconss[k].getAbsolutePath()+"thread");
//Log.d("Test", ddd[k]);
}
if (results&&ready)
{
dialogs.dismiss();
handlers.post(new MyRuns());
}
}
// else
// { dialogs.dismiss();
// handlers.post(new MyRunable());
//
// }
}finally {
}
}
}
public class MyRuns implements Runnable {
public void run() {
ready=true;
lv1.setAdapter(new BuddyAdapter(ctx,R.layout.list1,ddd,iconss));
onDestroy();
}
}
public class MyRunable implements Runnable {
public void run() {
//Toast.makeText(BuddyListActivity.this, "Your Connection is too slow", Toast.LENGTH_LONG).show();
startActivity(new Intent(BuddyListActivity.this,Anim.class));
}
}
}

use main thread to start your thread check runOnUiThread(Runnable action)

Setting RETURN in the try catch block and setting
android:noHistory="true" in Android Manifest for all activities fixed my problem

If you are trying to create an async task in a different thread I would recommend you to use the following class:
private final class MyRunnable extends
AsyncTask<Void, Void, Document> {
protected Document doInBackground(Void... params) {
}
protected void onPostExecute(Document result) {
}
}
You only have to change the parameters.
More info here:
http://developer.android.com/reference/android/os/AsyncTask.html

Finish your current activity when starting another activity from runnable .

android onSaveInstanceState usage

Please guide in the following class what I should save in.
Please remember I am using only one string which is I am retriving from getextra method and there is nothing which I think I should store in the following overridden method.
protected void onSaveInstanceState(Bundle outState) {
// TODO Auto-generated method stub
super.onSaveInstanceState(outState);
}
Can you guide me what to store in onsave instance method and what not to?
package com.wozzon.activity;
import java.util.ArrayList;
import org.json.JSONArray;
import org.json.JSONObject;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Intent;
import android.graphics.Typeface;
import android.os.Bundle;
import android.text.Html;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.AdapterView.OnItemClickListener;
import com.wozzon.json.JSONService;
import com.wozzon.model.SearchCriteria;
import com.wozzon.pl.UIFactory;
import com.wozzon.util.Util;
import com.wozzon.util.WLConstants;
public class HomeBrowse extends Activity implements OnItemClickListener{
private final static String TAG = HomeBrowse.class.getSimpleName();
private ArrayList<BrowseRow> model=new ArrayList<BrowseRow>();
private BrowseAdapter adapter;
private ListView list;
private TextView browseTitle;
private TextView changeLink;
private SearchCriteria sc =SearchCriteria.getInstance();
private JSONArray jsonArray;
private ProgressDialog m_ProgressDialog = null;
private Runnable progressRunnable;
#Override
public void onCreate(Bundle savedInstanceState) {
try {
super.onCreate(savedInstanceState);
setContentView(R.layout.browse);
String errorMsg =Util.getExtraValue(getIntent().getExtras(), WLConstants.ERROR_MSG);
list =(ListView)findViewById(R.id.browse_cats);
if(errorMsg!= null){
UIFactory.displayAlert(new AlertDialog.Builder(HomeBrowse.this), "Status", errorMsg);
}
progressRunnable = new Runnable(){
#Override
public void run() {
try {
loadData();
} catch (Throwable e) {
Log.e(TAG, e.getMessage());
}
runOnUiThread(returnRes);
}
};
m_ProgressDialog = ProgressDialog.show(HomeBrowse.this,
"Please wait...", "Loading ...", true);
Thread thread = new Thread(progressRunnable);
thread.start();
} catch (Throwable e) {
Log.e(TAG, e.getMessage());
Util.handleError(HomeBrowse.this, HomeBrowse.class, e.getMessage());
//UIFactory.displayAlert(new AlertDialog.Builder(HomeBrowse.this), "Error Loading categories", e.getMessage());
}
}
private void loadData()throws Throwable{//loading object
jsonArray = JSONService.getJsonArray(getResources().getString(R.string.catJson));
}
private void fillResultRows(JSONArray jsonArray, BrowseAdapter adapter)throws Throwable{
BrowseRow br = null;
try {
for(int a=0; a<jsonArray.length(); a++){
JSONObject jsonObj = jsonArray.getJSONObject(a);
br = new BrowseRow();
br.name=jsonObj.getString("title");
br.image=jsonObj.getString("image");
br.searchType = jsonObj.getInt("searchType");
if(jsonObj.has("categoryIds")){
br.categoryIds = jsonObj.getString("categoryIds").replaceAll("-", ",");
}
if(jsonObj.has("subCategoryIds")){
br.subCategoryIds = jsonObj.getString("subCategoryIds").replaceAll("-", ",");
}
adapter.add(br);
}
} catch (Throwable e) {
throw e;
}
}
class BrowseAdapter extends ArrayAdapter<BrowseRow> {
BrowseAdapter() {
super(HomeBrowse.this, android.R.layout.simple_list_item_1, model);
}
public View getView(int position, View convertView,
ViewGroup parent) {
View row=convertView;
ResultWrapper wrapper=null;
if (row==null) {
LayoutInflater inflater=getLayoutInflater();
row=inflater.inflate(R.layout.browse_row, null);
wrapper=new ResultWrapper(row);
row.setTag(wrapper);
}
else {
wrapper=(ResultWrapper)row.getTag();
}
wrapper.populateFrom(model.get(position));
return(row);
}
}
class ResultWrapper {
private TextView name;
private String catIds="0";
private String subCatIds="0";
private ImageView image;
private int searchType;
private View row=null;
ResultWrapper(View row) {
this.row=row;
}
void populateFrom(BrowseRow r) {
getName().setText(r.name);
getIcon().setImageResource(getImageIcon(Integer.parseInt(r.image)));
catIds =r.categoryIds;
subCatIds = r.subCategoryIds;
searchType =r.searchType;
}
TextView getName() {
if (name==null) {
name=(TextView)row.findViewById(R.id.browse_row_name);
}
return name;
}
ImageView getIcon() {
if (image==null) {
image=(ImageView)row.findViewById(R.id.browse_row_icon);
}
return image;
}
}
private int getImageIcon(int catId){
int imageSource=R.drawable.all_cats;
switch(catId){
case WLConstants.CATEGORY_FILM: imageSource =R.drawable.film; break;
case WLConstants.CATEGORY_MUSIC: imageSource =R.drawable.music; break;
case WLConstants.CATEGORY_ARTS: imageSource =R.drawable.art; break;
case WLConstants.CATEGORY_KIDS: imageSource =R.drawable.museum; break;
case WLConstants.CATEGORY_GALLERY_MUSEUM: imageSource =R.drawable.kids; break;
case WLConstants.CATEGORY_COMEDY: imageSource =R.drawable.comedy; break;
case WLConstants.CATEGORY_NIGHT_CLUBS: imageSource =R.drawable.clubs; break;
case WLConstants.CATEGORY_ATTRACTION: imageSource =R.drawable.touristattractions; break;
case WLConstants.CATEGORY_VARIOUS_EVENTS: imageSource =R.drawable.all_cats; break;
case WLConstants.CATEGORY_ALL_FOOD_DRINK: imageSource =R.drawable.restaurants; break;
}
return imageSource;
}
#Override
public void onItemClick(AdapterView<?> adp, View view, int item, long arg3) {
try {
if("".equals(sc.getSearchLocation()) && (!(Util.locationFound(sc.getGeoLocation()) && sc.isUK()))){
UIFactory.displayAlert(new AlertDialog.Builder(HomeBrowse.this), "Error", "Please provide location");
return;
}
ResultWrapper wrap = (ResultWrapper)view.getTag();
sc.setCategoryIds(wrap.catIds);
sc.setSubCategoryIds(wrap.subCatIds);
sc.setSearchType(wrap.searchType);
goSearch();
} catch (Throwable e) {
Log.e(TAG, e.getMessage());
Util.handleError(HomeBrowse.this, HomeBrowse.class, e.getMessage());
//UIFactory.displayAlert(new AlertDialog.Builder(this), "Error", e.getMessage());
}
}
private void applyListener(){
list.setOnItemClickListener(this);
changeLink.setOnClickListener(onclickListener);
}
private final void goSearch(){
try {
sc.setSearchString("");
Intent mainIntent = new Intent(HomeBrowse.this,SearchResults.class);
startActivity(mainIntent);
} catch (Throwable e) {
Log.e(TAG, e.getMessage());
Util.handleError(HomeBrowse.this, HomeBrowse.class, e.getMessage());
}
}
public OnClickListener onclickListener = new OnClickListener(){
// #Override
public void onClick(View aView) {
try {
int componentId =aView.getId();
switch(componentId){
case R.id.tv_changeDateType:
Intent intent = new Intent(HomeBrowse.this,TimeLocationSettings.class);
startActivity(intent);
break;
}
} catch (Exception e) {
Log.e(TAG, e.getMessage());
Util.handleError(HomeBrowse.this, HomeBrowse.class, e.getMessage());
}
}
};
private void configComponents(){
String titleStr,location = "";
String dateCrtStr = Util.getDateCritieraStr(sc.getDateCriteria());
titleStr= dateCrtStr;
if(!"".equals(sc.getSearchLocation())){
location = sc.getSearchLocation();
}else if(sc.isNearMe()){
location="Near me";
}else{
location = "Postcode or town";
}
titleStr = titleStr + " - "+ location;
browseTitle.setText(titleStr);
changeLink.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
}
public class BrowseRow {
private String name = "";
private String image = "";
private String categoryIds="0";
private String subCategoryIds="0";
private int searchType=1;
}
private Runnable returnRes = new Runnable() {
#Override
public void run() {
try {
browseTitle = (TextView)findViewById(R.id.browsePageTite);
changeLink = (TextView)findViewById(R.id.tv_changeDateType);
changeLink.setText(Html.fromHtml("<a href='#'>Change</a>"));
adapter=new BrowseAdapter();
applyListener();
configComponents();
fillResultRows(jsonArray, adapter);
if(jsonArray == null){
UIFactory.displayAlert(new AlertDialog.Builder(HomeBrowse.this), "Error", "Error Loading categories");
return;
}
list.setAdapter(adapter);
} catch (Throwable e) {
e.printStackTrace();
}
m_ProgressDialog.dismiss();
}
};
}

Not necessarily everything, because
The default implementation takes care of most of the UI per-instance state for you by calling onSaveInstanceState() on each view in the hierarchy that has an id, and by saving the id of the currently focused view (all of which is restored by the default implementation of onRestoreInstanceState(Bundle)).
via http://developer.android.com/reference/android/app/Activity.html#onSaveInstanceState(android.os.Bundle)
but if you override, you have to handle entire state by yourself.

You should be saving everything that describes the view's state that isn't saved elsewhere.
Save where the user is in a EditText, what value the EditText has, what dialog is currently displayed, etc. Your application should be able to reconstruct the exact state it was in from the bundle returned to in when it is paused by the user leaving the application and returning to it.