AsyncTask with ProgressBar and Xml parsing using DOM parser

AsynCall.java ::

package com.web;

import java.util.logging.Level;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.w3c.dom.Document;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.os.AsyncTask;

public class Async extends AsyncTask<String, Void, Document> {

public ProgressDialog pDialog;
Context context;
public boolean isRunning = false;
AsyncListener listener;
public boolean isCancelled = false;
String errorMessage;
boolean isError = false;
public String message = "Loading please wait...";
Document doc;
DefaultHttpClient client;
HttpParams httpParameters;

public Async(Context context) {
this.context = context;
pDialog = new ProgressDialog(context);
pDialog.setMessage(message);
pDialog.setOnCancelListener(new DialogInterface.OnCancelListener() {

@Override
public void onCancel(DialogInterface arg0) {
cancel(true);
}
});
client = new DefaultHttpClient(httpParameters);
}

@Override
protected Document doInBackground(String... params) {
try {
pDialog.setCancelable(false);
HttpGet uri = new HttpGet("Your Url.");
httpParameters = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParameters, 4000);
HttpConnectionParams.setSoTimeout(httpParameters, 5000);
client = new DefaultHttpClient(httpParameters);
HttpResponse resp = client.execute(uri);
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = db.parse(resp.getEntity().getContent());
return doc;
} catch (Exception e) {
     e.printStack();
return null;
}
}

public void setAsyncListener(AsyncListener listener) {
this.listener = listener;
}

public void setProggressDialogMessage(String msg) {
this.message = msg;
}

@Override
protected void onPostExecute(Document doc) {
pDialog.dismiss();
if (listener != null) {
if (isError) {
listener.onErrorReceived(errorMessage);
} else
listener.onResponseReceived(doc);
}
}

@Override
protected void onPreExecute() {
pDialog.setMessage(message);
showProgressbar();
}

private void showProgressbar() {
if (!isCancelled) {
pDialog.show();
}
}

@Override
protected void onCancelled() {
pDialog.dismiss();
super.onCancelled();
isCancelled = true;
}
}

AsyncListener.java ::

package com.web;
import org.w3c.dom.Document;

public interface AsyncListener {
  public void onResponseReceived(Document doc);
public void onErrorReceived(String str);
}

AsyncActivity.java ::

public class AsyncActivity  extends BaseActivity{

public AsyncCall asyncCall;

private Async async;

@Override

public void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

asyncCall = (AsyncCall) getLastNonConfigurationInstance();

  

if (asyncCall == null) {

asyncCall = new AsyncCall(this);

}

async = (Async) getLastNonConfigurationInstance();

if (async == null) {

async = new Async(this);

}

}

  

@Override

public void onResume() {

if(async != null && async.isRunning && async.pDialog != null && !async.pDialog.isShowing()) {

async.pDialog.setMessage(async.message);

async.pDialog.show();

}

else if(async != null && !async.isRunning && async.pDialog.isShowing()) {

async.pDialog.dismiss();

}

if(asyncCall != null && asyncCall.isRunning && asyncCall.pDialog != null && !asyncCall.pDialog.isShowing()) {

asyncCall.pDialog.setMessage(asyncCall.message);

asyncCall.pDialog.show();

}

else if(asyncCall != null && !asyncCall.isRunning && asyncCall.pDialog.isShowing()) {

asyncCall.pDialog.dismiss();

}

super.onResume();

}

    @Override

    protected void onPause() {

    super.onPause();

    }

}

XMLParser :: 


public class XMLParser {

/**
* Getting XML from URL making HTTP request
* @param url string
* */

public String getXmlFromUrl(String url) {

String xml = null;
try {

       DefaultHttpClient httpClient = new DefaultHttpClient();

       HttpPost httpPost = new HttpPost(url);
        HttpResponse httpResponse = httpClient.execute(httpPost);
      HttpEntity httpEntity = httpResponse.getEntity();
      xml = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return xml;
}

/**
* Getting XML DOM element
* @param XML string
* */
public Document getDomElement(String xml){
Document doc = null;
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try {
DocumentBuilder db = dbf.newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(xml));
doc = db.parse(is);
} catch (ParserConfigurationException e) {
return null;
} catch (SAXException e) {
return null;
} catch (IOException e) {
return null;
}
return doc;
}
/** Getting node value
* @param elem element
*/
public final String getElementValue( Node elem ) {
Node child;
if( elem != null){
if (elem.hasChildNodes()){
for( child = elem.getFirstChild(); child != null; child = child.getNextSibling() ){
if( child.getNodeType() == Node.TEXT_NODE  ){
return child.getNodeValue();
}
}
}
}
return "";
}
/**
* Getting node value
* @param Element node
* @param key string
* */
public String getValue(Element item, String str) {
NodeList n = item.getElementsByTagName(str);
return this.getElementValue(n.item(0));
}


// code snipest ::


NodeList nl,statelist;
nl= doc.getElementsByTagName("country");
XMLParser parser = new XMLParser();
// looping through all item nodes <item>
if(nl != null) {
for (int i = 0; i < nl.getLength(); i++) {
Country country_obj = new Country();
Element e = (Element) nl.item(i);

country_obj.c_id = parser.getValue(e, "id");
country_obj.c_name = parser.getValue(e, "c_name");
statelist = e.getElementsByTagName("state");
------------------------------------

}
}