Develop Reference

Add Update and Delete Item from Listview on Server Response Dynamically

Hi I don't know asking proper question or not but i want to develop Like Comment on Facebook post, Update comment and Delete Comment.
When i will add comment it will send request to server and it will give response with new values to fill in listadapter and that change may appear on my listview after click on enter or add button, and on delete it will send request to server and in response fill my listAdapter. and change may appear on my listview without refreshing listview. how can i perform this operation .
Thank You in Adavance.
Here is my Class.
public class CommmentActivity extends Activity{
DatabaseHandler db = new DatabaseHandler(this);
List<CommentListInfo> list_CommentInfo = new ArrayList<CommentListInfo>();
List<String> SuggetionList;
AutoCompleteTextView aCompletView;
EditText etComment;
String strComment;
ArrayAdapter<String> mentionList;
ListCommentAdapter commentAdapter;
ImageView IvAddComment;
ListView CommentList;
SessionCreator m_session;
boolean m = false;
boolean mBuzy;
int FirstPosition;
int ItemCounted;
int CurrentScrollState;
int TotalItemCount;
String UserId;
String VidoId;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.commentvideo_main);
SuggetionList = new ArrayList<String>();
String Curl = GlobalMethod.TokenGenerator() + "&action=getCommentsVideo";
Intent data = getIntent();
UserId = data.getStringExtra("userId");
VidoId = data.getStringExtra("videoId");
init();
String strfriendsSyncDate = m_session.getfriendsSyncDate();
Log.d("mData", strfriendsSyncDate);
new CommentsDetail().execute(UserId,VidoId,strfriendsSyncDate,Curl,"1");
commentAdapter = new ListCommentAdapter(getApplicationContext(), list_CommentInfo);
CommentList.setAdapter(commentAdapter);
CommentList.setOnScrollListener(new OnScrollListener() {
#Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
// TODO Auto-generated method stub
switch (scrollState) {
case OnScrollListener.SCROLL_STATE_IDLE:{
commentAdapter.notifyDataSetChanged();
//ManipulateVisibleView(view);
break;
}
case OnScrollListener.SCROLL_STATE_TOUCH_SCROLL:
{
mBuzy = true;
break;
}
case OnScrollListener.SCROLL_STATE_FLING:{
mBuzy = true;
break;
}
default:
break;
}
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
// TODO Auto-generated method stub
FirstPosition = firstVisibleItem;
ItemCounted = visibleItemCount;
TotalItemCount = totalItemCount;
int LastPosition = view.getLastVisiblePosition();
Log.d("First Position", ""+FirstPosition);
Log.d("ItemCountes",""+ItemCounted);
Log.d("totalItemCount",""+TotalItemCount);
Log.d("LastPosition",""+LastPosition);
if(visibleItemCount!=0 && ((firstVisibleItem+visibleItemCount)>=(totalItemCount))){
Log.d("mCalled", "call");
}
isScrollCompleted();
}
});
IvAddComment.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
strComment = etComment.getText().toString();
etComment.getText().clear();
String strUrl = GlobalMethod.TokenGenerator() + "&action=addCommentsVideo";
new CommentsDetail().execute(UserId,VidoId,strComment,strUrl,"0");
commentAdapter.notifyDataSetChanged();
}
});
}
private void isScrollCompleted(){
if(this.ItemCounted >0 && this.CurrentScrollState == OnScrollListener.SCROLL_STATE_IDLE){
Log.d("ItemCounted",""+ItemCounted);
Log.d("CurrentScrollState",""+CurrentScrollState);
}
}
private void init() {
// TODO Auto-generated method stub
m_session = new SessionCreator(getApplicationContext());
etComment = (EditText)findViewById(R.id.etComments);
CommentList = (ListView)findViewById(R.id.lvLatestComments);
IvAddComment = (ImageView)findViewById(R.id.addComment);
}
public class CommentsDetail extends AsyncTask<String, String, String>{
#Override
protected String doInBackground(String... params) {
// TODO Auto-generated method stub
ServiceHandler serviceClient;
String mJsonString;
try{
String userId = (String)params[0];
String vId = (String)params[1];
if(params[4].equals("0")){
String comment = (String)params[2];
String strUrl = (String)params[3];
List<NameValuePair> paramsNameValuePairs = new ArrayList<NameValuePair>();
paramsNameValuePairs.add(new BasicNameValuePair("userId", userId));
paramsNameValuePairs.add(new BasicNameValuePair("videoId", vId));
paramsNameValuePairs.add(new BasicNameValuePair("commentText", comment));
serviceClient = new ServiceHandler();
mJsonString = serviceClient.makeServiceCall(strUrl,
ServiceHandler.POST, paramsNameValuePairs);
Log.i("---->>>>>>>>>>", paramsNameValuePairs + "");
}else{
String syncdate = (String)params[2];
String strUrl = (String)params[3];
List<NameValuePair> paramsNameValuePairs = new ArrayList<NameValuePair>();
paramsNameValuePairs.add(new BasicNameValuePair("userId", userId));
paramsNameValuePairs.add(new BasicNameValuePair("videoId", vId));
paramsNameValuePairs.add(new BasicNameValuePair("friendsSyncDate", syncdate));
serviceClient = new ServiceHandler();
mJsonString = serviceClient.makeServiceCall(strUrl,
ServiceHandler.POST, paramsNameValuePairs);
Log.i("---->>>>>>>>>>", paramsNameValuePairs + "");
}
Log.d("Response Json-----------------------",mJsonString );
return mJsonString;
}catch (Exception e) {
e.getStackTrace();
}
return null;
}
#SuppressWarnings({ "unchecked", "unchecked", "unchecked" })
#Override
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
try{
if (result != null) {
JSONObject responsJsonObj = new JSONObject(result);
JSONObject jsonObj = (JSONObject) responsJsonObj
.optJSONObject("data");
try {
String str = jsonObj.getString("error");
if ( str != null || str.length() != 0) {
// error
//Toast.makeText(NewsfeedActivity.this, jsonObj.getString("error"),Toast.LENGTH_LONG).show();
return;
}
} catch (JSONException je) {
Log.d("jex ------>", "" + je.getMessage());
try {
String str = jsonObj.getString("message");
Log.d("message=", "" + str);
if ( str != null || str.length() != 0) {
// VALID RESPONSE, NOW PARSE IT
if (jsonObj.has("comments")) {
JSONArray colArray = jsonObj.getJSONArray("comments");
Log.d("Colunm Array", ""+colArray);
int nComments = colArray.length();
Log.d("# comments", "" + nComments);
for(int i=0; i<nComments; i++){
JSONObject obj = colArray.getJSONObject(i);
Gson Comments = new Gson();
String strComments = Comments.toJson(obj);
Log.d("# obj=", "" + obj.toString());
CommentListInfo cmtInfo = new CommentListInfo();
cmtInfo.c_userId = obj.getString("userId");
cmtInfo.c_name = obj.getString("name");
cmtInfo.DateAdded = obj.getString("dateAdded");
cmtInfo.CommentId = obj.getString("commentId");
cmtInfo.CommentText = obj.getString("text");
cmtInfo.ImageUrl = obj.getString("imageLink");
list_CommentInfo.add(cmtInfo);
}
}
}
if ( str != null || str.length() != 0) {
// VALID RESPONSE, NOW PARSE IT
if (jsonObj.has("addPosition")) {
Log.d("# obj=", "" + jsonObj.toString());
Log.d("Add Position", jsonObj.getString("addPosition"));
}
}
//
if ( str != null || str.length() != 0) {
// VALID RESPONSE, NOW PARSE IT
if (jsonObj.has("friendsSyncDate")) {
Log.d("# friendsDeleted", "" + jsonObj);
Log.d("# obj=", "" + jsonObj.toString());
String myString = m_session.getfriendsSyncDate();
Log.d("myString", myString);
m_session.putfriendsSyncDate(jsonObj.getString("friendsSyncDate"));
Log.d("Sync Date "," "+jsonObj.getString("friendsSyncDate"));
}
}
} catch (JSONException je2) {
je2.printStackTrace();
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
Here is my Adapter Class.
public class ListCommentAdapter extends BaseAdapter{
private Context mContext;
private List<CommentListInfo> CommentsInfo;
private LayoutInflater inflater;
private String szUserId;
private String szVideoID;
private boolean mBuzy = false;
public ListCommentAdapter(Context context, List<CommentListInfo> cmtInfo) {
// TODO Auto-generated constructor stub
mContext = context;
CommentsInfo = cmtInfo;
AppData mmap = (AppData)this.mContext.getApplicationContext();
szUserId = mmap.getUserId();
}
#Override
public int getCount() {
// TODO Auto-generated method stub
return CommentsInfo.size();
}
#Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return CommentsInfo.get(position);
}
#Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
Holder holder = new Holder();
CommentListInfo c = CommentsInfo.get(position);
try{
Log.i("nUserId", c.c_userId);
Log.i("nName", c.c_name);
Log.i("nCommentId", c.CommentId);
Log.i("nCommnet", c.CommentText);
Log.i("nImageUrl",c.ImageUrl);
}catch(Exception e){
Log.e("Erore is",""+e);
}
try{
if(inflater==null){
inflater = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
if(convertView==null){
convertView = inflater.inflate(R.layout.comment_list_item, null);
holder.ciProfileImage = (CircleImageView)convertView.findViewById(R.id.civCFLeftPic);
holder.tvComments = (TextView)convertView.findViewById(R.id.tvCommentbox);
holder.tvCDate = (TextView)convertView.findViewById(R.id.tvCfNotifyDate);
holder.tvName = (TextView)convertView.findViewById(R.id.tvCommentName);
convertView.setTag(holder);
}else{
holder = (Holder)convertView.getTag();
}
if(!mBuzy){
RemoteImageLoader task = new RemoteImageLoader();
task.setImageView(holder.ciProfileImage);
task.execute(c.ImageUrl);
Log.d("ImagerUrl", c.ImageUrl);
if(c.ImageUrl!=null){
Picasso.with(mContext)
.load(R.drawable.world1)
.placeholder(R.drawable.world1)
.error(R.drawable.world1)
.into(holder.ciProfileImage);
}else{
Picasso.with(mContext)
.load(R.drawable.world1)
.placeholder(R.drawable.world1)
.error(R.drawable.world1)
.into(holder.ciProfileImage);
}
holder.tvComments.setText(c.CommentText);
holder.tvCDate.setText(c.DateAdded);
holder.tvName.setText(c.c_name);
holder.tvComments.setTag(null);
}else{
holder.tvComments.setText("Loading...");
holder.tvComments.setTag(this);
}
return convertView;
}catch(Exception e){
System.out.println("Error IS :- "+ e);
}
return convertView;
}
private static class Holder{
private TextView tvName,tvComments,tvCDate;
private CircleImageView ciProfileImage;
}
}

You might have solved this already but I was working on a different app in Java and came across something similar. Mine was a bit simpler because I am using a local database but ~same thing. In your CommmentActivity's onCreate method pull out the commentAdapter declaration and the CommentList.setOnScrollListener and put them in their own method. Then call your newly defined commentAdapter method in onCreate and after you parse through the response.
Something like this
public void myAdaperMethod(Context context, List<CommentListInfo> list_CommentInfo){
commentAdapter = new ListCommentAdapter(this, list_CommentInfo);
CommentList.setAdapter(commentAdapter);
CommentList.setOnScrollListener(new OnScrollListener(){...}
}
onCreate{
myAdapterMethod(...);
}
post{...}
get{myAdapterMethod(...);}
Hope that helps.

You just need to re-bind your control after the listadapter has the new dataset.
CommentList.DataBind();

RSS feed images not shown using AsyncTask

I'm using AsyncTask trying to display the images of the rss feed. I'm catching the url of them from my RSSHandler and I want the images to be shown in my custom ListView but there's nothing. May you help me please? I'm stuck with this.
Yhis is the message in the LogCat:
FATAL EXCEPTION: AsyncTask #1
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:299)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
at java.util.concurrent.FutureTask.run(FutureTask.java:239)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:856)
Caused by: java.lang.NullPointerException: println needs a message
at android.util.Log.println_native(Native Method)
at android.util.Log.d(Log.java:138)
at com.riccardo.myapplication.DownloadImagesTask.download_Image(DownloadImagesTask.java:42)
at com.riccardo.myapplication.DownloadImagesTask.doInBackground(DownloadImagesTask.java:20)
at com.riccardo.myapplication.DownloadImagesTask.doInBackground(DownloadImagesTask.java:13)
at android.os.AsyncTask$2.call(AsyncTask.java:287)
at java.util.concurrent.FutureTask.run(FutureTask.java:234)
This is my Handler (edited):
public class RSSHandler extends DefaultHandler {
final int state_unknown = 0;
final int state_title = 1;
final int state_description = 2;
final int state_link = 3;
final int state_pubdate = 4;
int currentState = state_unknown;
ImageView imm;
RSSFeed feed;
RSSItem item;
boolean itemFound = false;
RSSHandler(){
}
RSSFeed getFeed(){
return feed;
}
#Override
public void startDocument() throws SAXException {
// TODO Auto-generated method stub
feed = new RSSFeed();
item = new RSSItem();
}
#Override
public void endDocument() throws SAXException {
// TODO Auto-generated method stub
}
#Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
// TODO Auto-generated method stub
if (localName.equalsIgnoreCase("item")){
itemFound = true;
item = new RSSItem();
currentState = state_unknown;
}
if ("enclosure".equals(qName)) {
int i;
for (i = 0; i < attributes.getLength(); i++)
if (attributes.getQName(i).equals("url")) ;
String url = attributes.getValue(i);
DownloadImagesTask downloadImages = new DownloadImagesTask(imm);
downloadImages.execute(url);
}
else if (localName.equalsIgnoreCase("title")){
currentState = state_title;
}
else if (localName.equalsIgnoreCase("description")){
currentState = state_description;
}
else if (localName.equalsIgnoreCase("link")){
currentState = state_link;
}
else if (localName.equalsIgnoreCase("pubdate")){
currentState = state_pubdate;
}
else{
currentState = state_unknown;
}
}
#Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
// TODO Auto-generated method stub
if (localName.equalsIgnoreCase("item")){
feed.addItem(item);
}
}
#Override
public void characters(char[] ch, int start, int length)
throws SAXException {
// TODO Auto-generated method stub
String strCharacters = new String(ch,start,length);
if (itemFound==true){
// "item" tag found, it's item's parameter
switch(currentState){
case state_title:
item.setTitle(strCharacters);
break;
case state_description:
item.setDescription(strCharacters);
break;
case state_link:
item.setLink(strCharacters);
break;
case state_pubdate:
item.setPubdate(strCharacters);
break;
default:
break;
}
}
else{
// not "item" tag found, it's feed's parameter
switch(currentState){
case state_title:
feed.setTitle(strCharacters);
break;
case state_description:
feed.setDescription(strCharacters);
break;
case state_link:
feed.setLink(strCharacters);
break;
case state_pubdate:
feed.setPubdate(strCharacters);
break;
default:
break;
}
}
currentState = state_unknown;
}
this my AsyncTask (edited):
public class DownloadImagesTask extends AsyncTask<String, Void, Bitmap> {
ImageView imageView = null;
String log = null;
public DownloadImagesTask(ImageView imageView){
//Put logic you need in the constructor
this.imageView = imageView;
}
#Override
protected Bitmap doInBackground(String... Urls) {
return download_Image(Urls[0]);
}
private Bitmap download_Image(String url) {
Bitmap bmp =null;
try{
URL ulrn = new URL(url);
HttpURLConnection con = (HttpURLConnection)ulrn.openConnection();
InputStream is = con.getInputStream();
bmp = BitmapFactory.decodeStream(is);
if (null != bmp)
return bmp;
}
catch(Exception e){
e.printStackTrace();
Log.d(log, "url= " + url);
}
return bmp;}
#Override
protected void onPostExecute(Bitmap result) {
imageView.setImageBitmap(result);
}
and this my custom ListView (edited):
public class CustomList extends ArrayAdapter<RSSItem> {
private final Activity context;
private final List<RSSItem> web;
private String url;
private AssetManager assets;
public CustomList(Activity context, List<RSSItem> web) {
super(context, R.layout.list_item, web);
this.context = context;
this.web = web;
this.url = url;
}
#Override
public View getView(int position, View view, ViewGroup parent) {
LayoutInflater inflater = context.getLayoutInflater();
final View rowView = inflater.inflate(R.layout.list_item, null, true);
Typeface myTypeface = Typeface.createFromAsset(context.getAssets(), "BPreplay.otf");
if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
}
final TextView txtTitle = (TextView) rowView.findViewById(R.id.item);
txtTitle.setText(web.get(position).getTitle());
txtTitle.setTypeface(myTypeface);
final TextView txtTitle2 = (TextView) rowView.findViewById(R.id.item2);
txtTitle2.setText(web.get(position).getDescription() + "...");
txtTitle2.setTypeface(myTypeface);
TextView txtTitle3 = (TextView) rowView.findViewById(R.id.pub);
txtTitle3.setText(web.get(position).getPubdate());
txtTitle3.setTypeface(myTypeface);
final TextView txtTitle4 = (TextView) rowView.findViewById(R.id.linke);
txtTitle4.setText("vai all'articolo completo --> " + web.get(position).getLink());
txtTitle4.setTypeface(myTypeface);
Button btn = (Button)rowView.findViewById(R.id.btn_share);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent sendIntent = new Intent();
sendIntent.setAction(Intent.ACTION_SEND);
sendIntent.putExtra(Intent.EXTRA_TEXT, "Leggi " +"''" + txtTitle.getText().toString()
+ ": " + txtTitle2.getText().toString()
+ txtTitle4.getText().toString() + "'' " + "Condiviso da Active News");
sendIntent.setType("text/plain");
context.startActivity(Intent.createChooser(sendIntent, rowView.getResources().getText(R.string.chooser_title)));
}
});
ImageView img = (ImageView)rowView.findViewById(R.id.immagine_feed);
DownloadImagesTask downloadImages = new DownloadImagesTask(img);
downloadImages.execute(url);
return rowView;
}
}

The issue occurs here:
#Override
protected Bitmap doInBackground(ImageView... imageViews) {
this.imageView = imageViews[0];
return download_Image((String)imageView.getTag());
}
download_Image takes a url as a string parameter, why are you passing the imageView.getTag();
Change your asyncTask to something like this:
public class DownloadImagesTask extends AsyncTask<String, Void, Bitmap> {
ImageView imageView = null;
public DownloadImagesTask(ImageView imageView){
//Put logic you need in the constructor
this.imageView = imageView;
}
#Override
protected Bitmap doInBackground(String... Urls) {
return download_Image(Urls[0]);
}
#Override
protected void onPostExecute(Bitmap result) {
imageView.setImageBitmap(result);
}
}
So when you call it you would pass an imageView to the constructor, then pass a string url to the execute method of the asyntask:
DownloadImagesTask downloadImages = new DownloadImagesTask(someImageView);
downloadImages.execute("http://www.yoururl.com/api/");
EDIT:
Run the task right after you get the both url and imageview.
public CustomList(Activity context, List<RSSItem> web, String url) {
super(context, R.layout.list_item, web);
this.context = context;
this.web = web;
this.url = url;
}
DownloadImagesTask downloadImages = new DownloadImagesTask(img);
downloadImages.execute(url);
make sure you have a url Log.d(log, "url= " + url);

Android Async XML Parsing

I was trying to parse XML from a url and show it on a listview. But, listview is showing
like this
http://postimg.org/image/ucbdjpwj5/
[I can't post any image directly here, because my reputation is under 10 ]
Here are my code
MainActivity
getRssDataTask ts = new getRssDataTask();
ts.execute("http://www.xyzapp.com/feed");
}
private class getRssDataTask extends AsyncTask<String, Void, List<NewsItem>>{
#Override
protected List<NewsItem> doInBackground(String... params) {
// TODO Auto-generated method stub
try {
// Create RSS reader
RSSReader rssReader = new RSSReader(params[0]);
// Parse RSS, get items
return rssReader.getItems();
} catch (Exception e) {
Log.e("App", e.getMessage());
}
return null;
}
#Override
protected void onPostExecute(List<NewsItem> result) {
ListView Items = (ListView) findViewById(R.id.listView);
// Create a list adapter
ArrayAdapter<NewsItem> rs = new ArrayAdapter<NewsItem>(local,android.R.layout.simple_list_item_1, result);
// Set list adapter for the ListView
Items.setAdapter(rs);
RssHandler
public class RssHandler extends DefaultHandler {
private List<NewsItem> rssItem;
private NewsItem currentItem;
private boolean parsingTitle;
private boolean parsingDes;
public RssHandler() {
// TODO Auto-generated constructor stub
rssItem = new ArrayList<NewsItem>();
}
public List<NewsItem> getItems() {
return rssItem;
}
#Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
// TODO Auto-generated method stub
if ("item".equals(qName)) {
currentItem = new NewsItem();
} else if ("title".equals(qName)) {
parsingTitle = true;
} else if ("content:encoded".equals(qName)) {
parsingDes = true;
}
}
#Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
// TODO Auto-generated method stub
if ("item".equals(qName)) {
rssItem.add(currentItem);
currentItem = null;
} else if ("title".equals(qName)) {
parsingTitle = false;
} else if ("content:encoded".equals(qName)) {
parsingDes = false;
}
}
#Override
public void characters(char[] ch, int start, int length)
throws SAXException {
// TODO Auto-generated method stub
if (parsingTitle) {
if (currentItem != null)
currentItem.setTitle(new String(ch, start, length));
} else if (parsingDes) {
if (currentItem != null) {
currentItem.setDes(new String(ch, start, length));
parsingDes = false;
}
}
}
}
RssReader
public class RSSReader {
private String RssUrl;
public RSSReader(String RssUrl) {
// TODO Auto-generated constructor stub
this.RssUrl = RssUrl;
}
public List<NewsItem> getItems() throws Exception{
SAXParserFactory factory = SAXParserFactory.newInstance();
SAXParser saxParser = factory.newSAXParser();
RssHandler handler = new RssHandler();
saxParser.parse(RssUrl, handler);
return handler.getItems();
}
}
I was unable to figure out the problem. My question is what wrong I am doing ?

Implement the following method in NewsItem:
#Override
public String toString() {
// return a String value representing this object
// Assuming two class String properties called title and description
return title + ": " + description;
}

Parsing CDATA in android RSS

I'm trying to make an ANDROID app that reads RSS feeds so I used this tutorial ( http://android-er.blogspot.com/2010/05/simple-rss-reader-ii-implement-with.html ) and implemented it to my own url rss feeder. But the description tag isn't being shown..mostly cz in the xml of the feeder the description tags are CDATA. how can i parse the description cdata in my rss??Thanks!
here is my RSSHandler code :
import org.xml.sax.Attributes;
import org.xml.sax.SAXException; import org.xml.sax.helpers.DefaultHandler;
public class RSSHandler extends DefaultHandler {
final int state_unknown = 0;
final int state_title = 1;
final int state_description = 2;
final int state_link = 3;
final int state_pubdate = 4;
int currentState = state_unknown;
RSSFeed feed;
RSSItem item;
boolean itemFound = false;
RSSHandler(){
}
RSSFeed getFeed(){
return feed;
}
#Override
public void startDocument() throws SAXException {
// TODO Auto-generated method stub
feed = new RSSFeed();
item = new RSSItem();
}
#Override
public void endDocument() throws SAXException {
// TODO Auto-generated method stub
}
#Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
// TODO Auto-generated method stub
if (localName.equalsIgnoreCase("item")){
itemFound = true;
item = new RSSItem();
currentState = state_unknown;
}
else if (localName.equalsIgnoreCase("title")){
currentState = state_title;
}
else if (localName.equalsIgnoreCase("description")){
currentState = state_description;
}
else if (localName.equalsIgnoreCase("link")){
currentState = state_link;
}
else if (localName.equalsIgnoreCase("pubdate")){
currentState = state_pubdate;
}
else{
currentState = state_unknown;
}
}
#Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
// TODO Auto-generated method stub
if (localName.equalsIgnoreCase("item")){
feed.addItem(item);
}
}
#Override
public void characters(char[] ch, int start, int length)
throws SAXException {
// TODO Auto-generated method stub
String strCharacters = new String(ch,start,length);
if (itemFound==true){
// "item" tag found, it's item's parameter
switch(currentState){
case state_title:
item.setTitle(strCharacters);
break;
case state_description:
item.setDescription(strCharacters);
break;
case state_link:
item.setLink(strCharacters);
break;
case state_pubdate:
item.setPubdate(strCharacters);
break;
default:
break;
}
}
else{
// not "item" tag found, it's feed's parameter
switch(currentState){
case state_title:
feed.setTitle(strCharacters);
break;
case state_description:
feed.setDescription(strCharacters);
break;
case state_link:
feed.setLink(strCharacters);
break;
case state_pubdate:
feed.setPubdate(strCharacters);
break;
default:
break;
}
}
currentState = state_unknown;
}
and here is my RSSReader code :
public class AndroidRssReader extends ListActivity {
private RSSFeed myRssFeed = null;
//private ArrayList<RSSItem> myRssFeed = null;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
try {
//URL rssUrl = new URL("http://www.gov.hk/en/about/rss/govhkrss.data.xml");
URL rssUrl = new URL("http://www.merehbi.com/online/index.php?option=com_content&view=category&layout=blog&id=58&Itemid=155&lang=ar&format=feed&type=rss");
SAXParserFactory mySAXParserFactory = SAXParserFactory.newInstance();
SAXParser mySAXParser = mySAXParserFactory.newSAXParser();
XMLReader myXMLReader = mySAXParser.getXMLReader();
RSSHandler myRSSHandler = new RSSHandler();
myXMLReader.setContentHandler(myRSSHandler);
InputSource myInputSource = new InputSource(rssUrl.openStream());
myXMLReader.parse(myInputSource);
myRssFeed = myRSSHandler.getFeed();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ParserConfigurationException e) {
e.printStackTrace();
} catch (SAXException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
if (myRssFeed!=null)
{
TextView feedTitle = (TextView)findViewById(R.id.feedtitle);
TextView feedDescribtion = (TextView)findViewById(R.id.feeddescribtion);
TextView feedPubdate = (TextView)findViewById(R.id.feedpubdate);
TextView feedLink = (TextView)findViewById(R.id.feedlink);
feedTitle.setText(myRssFeed.getTitle());
feedDescribtion.setText(myRssFeed.getDescription());
feedPubdate.setText(myRssFeed.getPubdate());
feedLink.setText(myRssFeed.getLink());
ArrayAdapter<RSSItem> adapter =
new ArrayAdapter<RSSItem>(this,
android.R.layout.simple_list_item_1,myRssFeed.getList());
setListAdapter(adapter);
}
}
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
Intent intent = new Intent(this,ShowDetails.class);
Bundle bundle = new Bundle();
bundle.putString("keyTitle", myRssFeed.getItem(position).getTitle());
bundle.putString("keyDescription", myRssFeed.getItem(position).getDescription());
bundle.putString("keyLink", myRssFeed.getItem(position).getLink());
bundle.putString("keyPubdate", myRssFeed.getItem(position).getPubdate());
intent.putExtras(bundle);
startActivity(intent);
}
}

i use this tutorial and its codes
http://www.androidhive.info/2011/11/android-xml-parsing-tutorial/
and change some code by this answer
https://stackoverflow.com/a/8489223/3636653
public static void main(String[] args) throws Exception {
File file = new File("data.xml");
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(file);
NodeList nodes = doc.getElementsByTagName("topic");
for (int i = 0; i < nodes.getLength(); i++) {
Element element = (Element) nodes.item(i);
NodeList title = element.getElementsByTagName("title");
Element line = (Element) title.item(0);
System.out.println("Title: " + getCharacterDataFromElement(line));
}
}
public static String getCharacterDataFromElement(Element e) {
Node child = e.getFirstChild();
if (child instanceof CharacterData) {
CharacterData cd = (CharacterData) child;
return cd.getData();
}
return "";
}

How to Build a RSS reader for Android?

I am new to android and i am trying to build a RSS reader for Android. I have built all the classes and XML files but its not giving the required output. Its just showing the message
No RSS feed available.
Please can some one suggest what should i do.
Here is the code which i took from the tutorial and tried to manipulate-
public final String RSSFEEDOFCHOICE = "http://blog.01synergy.com/feed/";
public final String tag = "RSSReader";
private RSSFeed feed = null;
/** Called when the activity is first created. */
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
// go get our feed!
feed = getFeed(RSSFEEDOFCHOICE);
// display UI
UpdateDisplay();
}
private RSSFeed getFeed(String urlToRssFeed)
{
try
{
// setup the url
URL url = new URL(urlToRssFeed);
// create the factory
SAXParserFactory factory = SAXParserFactory.newInstance();
// create a parser
SAXParser parser = factory.newSAXParser();
// create the reader (scanner)
XMLReader xmlreader = parser.getXMLReader();
// instantiate our handler
RSSHandler theRssHandler = new RSSHandler();
// assign our handler
xmlreader.setContentHandler(theRssHandler);
// get our data via the url class
InputSource is = new InputSource(url.openStream());
// perform the synchronous parse
xmlreader.parse(is);
// get the results - should be a fully populated RSSFeed instance, or null on error
return theRssHandler.getFeed();
}
catch (Exception ee)
{
// if we have a problem, simply return null
return null;
}
}
public boolean onCreateOptionsMenu(Menu menu)
{
super.onCreateOptionsMenu(menu);
menu.add(0,0,0, "Choose RSS Feed");
menu.add(0,1,0, "Refresh");
Log.i(tag,"onCreateOptionsMenu");
return true;
}
public boolean onOptionsItemSelected(Menu item){
switch (((View) item).getId()) {
case 0:
Log.i(tag,"Set RSS Feed");
return true;
case 1:
Log.i(tag,"Refreshing RSS Feed");
return true;
}
return false;
}
private void UpdateDisplay()
{
TextView feedtitle = (TextView) findViewById(R.id.feedtitle);
TextView feedpubdate = (TextView) findViewById(R.id.feedpubdate);
ListView itemlist = (ListView) findViewById(R.id.itemlist);
if (feed == null)
{
feedtitle.setText("No RSS Feed Available");
return;
}
feedtitle.setText(feed.getTitle());
feedpubdate.setText(feed.getPubDate());
ArrayAdapter<RSSItem> adapter = new ArrayAdapter<RSSItem>(this,android.R.layout.simple_list_item_1,feed.getAllItems());
itemlist.setAdapter(adapter);
itemlist.setOnItemClickListener(this);
itemlist.setSelection(0);
}
public void onItemClick(AdapterView parent, View v, int position, long id)
{
Log.i(tag,"item clicked! [" + feed.getItem(position).getTitle() + "]");
Intent itemintent = new Intent(this,ShowDescription.class);
Bundle b = new Bundle();
b.putString("title", feed.getItem(position).getTitle());
b.putString("description", feed.getItem(position).getDescription());
b.putString("link", feed.getItem(position).getLink());
b.putString("pubdate", feed.getItem(position).getPubDate());
itemintent.putExtra("android.intent.extra.INTENT", b);
startSubActivity(itemintent,0);
}
private void startSubActivity(Intent itemintent, int i) {
// TODO Auto-generated method stub
}
}

This is my first approach to RSS Reader, It's no so dynamic and has boilerplate code but worked well for myself.
Usage:
RssParser parser = new RssParser(feedUrl);
Log.i("LOG", "Description: " + parser.getItem(3).description); //4th item's description
Class:
package com.uncocoder.course.app.feed_reader;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import android.util.Log;
public class RssParser extends DefaultHandler {
private StringBuilder content;
private boolean inChannel;
private boolean inImage;
private boolean inItem;
private ArrayList<Item> items = new ArrayList<Item>();
private Channel channel = new Channel();
private Item lastItem;
public RssParser(String url) {
try {
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
XMLReader xr = sp.getXMLReader();
URL sourceUrl = new URL(url);
xr.setContentHandler(this);
xr.parse(new InputSource(sourceUrl.openStream()));
}
catch (ParserConfigurationException e) {
e.printStackTrace();
}
catch (SAXException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
public class Item {
public String title;
public String description;
public String link;
public String category;
public String pubDate;
public String guid;
}
public class Channel {
public String title;
public String description;
public String link;
public String lastBuildDate;
public String generator;
public String imageUrl;
public String imageTitle;
public String imageLink;
public String imageWidth;
public String imageHeight;
public String imageDescription;
public String language;
public String copyright;
public String pubDate;
public String category;
public String ttl;
}
#Override
public void startDocument() throws SAXException {
Log.i("LOG", "StartDocument");
}
#Override
public void endDocument() throws SAXException {
Log.i("LOG", "EndDocument");
}
#Override
public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException {
if (localName.equalsIgnoreCase("image")) {
inImage = true;
}
if (localName.equalsIgnoreCase("channel")) {
inChannel = true;
}
if (localName.equalsIgnoreCase("item")) {
lastItem = new Item();
items.add(lastItem);
inItem = true;
}
content = new StringBuilder();
}
#Override
public void endElement(String uri, String localName, String qName) throws SAXException {
if (localName.equalsIgnoreCase("image")) {
inImage = false;
}
if (localName.equalsIgnoreCase("channel")) {
inChannel = false;
}
if (localName.equalsIgnoreCase("item")) {
inItem = false;
}
if (localName.equalsIgnoreCase("title")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.title = content.toString();
} else if (inImage) {
channel.imageTitle = content.toString();
} else if (inChannel) {
channel.title = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("description")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.description = content.toString();
} else if (inImage) {
channel.imageDescription = content.toString();
} else if (inChannel) {
channel.description = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("link")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.link = content.toString();
} else if (inImage) {
channel.imageLink = content.toString();
} else if (inChannel) {
channel.link = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("category")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.category = content.toString();
} else if (inChannel) {
channel.category = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("pubDate")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.pubDate = content.toString();
} else if (inChannel) {
channel.pubDate = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("guid")) {
if (content == null) {
return;
}
lastItem.guid = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("url")) {
if (content == null) {
return;
}
channel.imageUrl = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("width")) {
if (content == null) {
return;
}
channel.imageWidth = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("height")) {
if (content == null) {
return;
}
channel.imageHeight = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("language")) {
if (content == null) {
return;
}
channel.language = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("copyright")) {
if (content == null) {
return;
}
channel.copyright = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("ttl")) {
if (content == null) {
return;
}
channel.ttl = content.toString();
content = null;
}
}
#Override
public void characters(char[] ch, int start, int length) throws SAXException {
if (content == null) {
return;
}
content.append(ch, start, length);
}
public Item getItem(int index) {
return items.get(index);
}
}

Check following link, It's open source RSS reader for Android, You can download code for reference
http://code.google.com/p/android-rss/

There is a tutorial (including complete source code) on how to build an Android RSS reder here:
part 1 (complete application)
part 2 (application updated to parse image tags from desciption)
part 3 (application update with Android 3.0)
The tutorial uses SAX parser and includes a complete Android project that accesses an RSS feed and then displays the feed in a list view.
There still seems to be a lot of people interested in this - so if you are looking for an Android 3.0+ with fragments/async tasks etc, as well as complete application code, I have updated the posts again, and they can be found here!

You can download and check my project on google-play.
This project is about some turkish sport channels feeds. Lots of channels are in one application.
You can check source code of project on github.

Parse this type of Rss Feeds easily using XmlPullParser
public class RSSParser {
public static ArrayList<Pojo> getParserData(String Data){
try {
RSSXMLTag currentTag = null;
ArrayList<Pojo> postDataList = new ArrayList<>();
XmlPullParserFactory factory = XmlPullParserFactory
.newInstance();
factory.setNamespaceAware(true);
XmlPullParser xpp = factory.newPullParser();
xpp.setInput(new StringReader(Data));
int eventType = xpp.getEventType();
Pojo pdData = null;
SimpleDateFormat dateFormat = new SimpleDateFormat(
"EEEE, DD MMM yyyy ");
while (eventType != XmlPullParser.END_DOCUMENT) {
int i = 0;
if (eventType == XmlPullParser.START_DOCUMENT) {
} else if (eventType == XmlPullParser.START_TAG) {
if (xpp.getName().equals("item")) {
pdData = new Pojo();
currentTag = RSSXMLTag.IGNORETAG;
} else if (xpp.getName().equals("title")) {
currentTag = RSSXMLTag.TITLE;
} else if (xpp.getName().equals("link")) {
currentTag = RSSXMLTag.LINK;
} else if (xpp.getName().equals("pubDate")) {
currentTag = RSSXMLTag.DATE;
} else if (xpp.getName().equals("creator")) {
currentTag = RSSXMLTag.CREATOR;
} else if (xpp.getName().equals("category")) {
currentTag = RSSXMLTag.CATEGORY;
} else if (xpp.getName().equals("description")) {
currentTag = RSSXMLTag.DESCRIPTION;
}
} else if (eventType == XmlPullParser.END_TAG) {
if (xpp.getName().equals("item")) {
// format the data here, otherwise format data in
// Adapter
Date postDate = dateFormat.parse(pdData.postDate);
pdData.postDate = dateFormat.format(postDate);
postDataList.add(pdData);
} else {
currentTag = RSSXMLTag.IGNORETAG;
}
} else if (eventType == XmlPullParser.TEXT) {
String content = xpp.getText();
content = content.trim();
Log.d("debug", content);
if (pdData != null) {
switch (currentTag) {
case TITLE:
if (content.length() != 0) {
if (pdData.postTitle != null) {
pdData.postTitle += content;
} else {
pdData.postTitle = content;
}
}
break;
case LINK:
if (content.length() != 0) {
if (pdData.postLink != null) {
pdData.postLink += content;
} else {
pdData.postLink = content;
}
}
break;
case DATE:
if (content.length() != 0) {
if (pdData.postDate != null) {
pdData.postDate += content;
} else {
pdData.postDate = content;
}
}
break;
case CATEGORY:
if (content.length() != 0) {
if (pdData.postCategory != null) {
i = i + 1;
if (i == 1) {
pdData.postCategory = content;
}
} else {
i = i + 1;
if (i == 1) {
pdData.postCategory = content;
}
}
}
break;
case DESCRIPTION:
if (content.length() != 0) {
if (pdData.postDescription != null) {
String s = content;
String string = s.substring(s.indexOf("src=\"") + 5, s.indexOf("\" class=\""));
pdData.postDescription += string;
} else {
String s = content;
String string = s.substring(s.indexOf("src=\"") + 5, s.indexOf("\" class=\""));
pdData.postDescription = string;
}
}
break;
case CREATOR:
if (content.length() != 0) {
if (pdData.postCreator != null) {
pdData.postCreator += content;
} else {
pdData.postCreator = content;
}
}
break;
default:
break;
}
}
}
eventType = xpp.next();
}
return postDataList;
}catch (Exception e){
e.printStackTrace();
}
return null;
}
public enum RSSXMLTag {
IGNORETAG, TITLE, LINK, DATE,CREATOR,CATEGORY, DESCRIPTION;
}
public class Pojo {
public String getPostTitle() {
return postTitle;
}
public void setPostTitle(String postTitle) {
this.postTitle = postTitle;
}
public String getPostLink() {
return postLink;
}
public void setPostLink(String postLink) {
this.postLink = postLink;
}
public String getPostDate() {
return postDate;
}
public void setPostDate(String postDate) {
this.postDate = postDate;
}
public String getPostCategory() {
return postCategory;
}
public void setPostCategory(String postCategory) {
this.postCategory = postCategory;
}
public String getPostDescription() {
return postDescription;
}
public void setPostDescription(String postDescription) {
this.postDescription = postDescription;
}
public String getPostCreator() {
return postCreator;
}
public void setPostCreator(String postCreator) {
this.postCreator = postCreator;
}
public String postTitle;
public String postLink;
public String postDate;
public String postCategory;
public String postDescription;
public String postCreator;
}
}