Parse XML on Android

Question

I am trying to use the API for our billing system in an Android Application, but I am having trouble figuring out how to parse the XML that it returns. Here is what my funct

Answer 1

Yes SAX parser is the solution and here is the basic code to get you started:

void parseExampleFunction(){
    SAXParserFactory spf = SAXParserFactory.newInstance();
    SAXParser sp = spf.newSAXParser();
    XMLReader xr = sp.getXMLReader();

    File myFile = new File( //the XML file which you need to parse );
    myFile.createNewFile();

    FileInputStream fOut =  new FileInputStream(myFile);
    BufferedInputStream bos = new BufferedInputStream( fOut );

    /** Create handler to handle XML Tags ( extends DefaultHandler ) */

    MessagesXMLHandler myXMLHandler = new MessagesXMLHandler(context);
    xr.setContentHandler(myXMLHandler);
    xr.parse(new InputSource(bos));
}

// the class where the parsing logic needs to defined.This preferably can be in a different .java file 
public class MessagesXMLHandler extends DefaultHandler{

    //this function is called automatically when a start tag is encountered
    @Override
    public void startElement(String uri, String localName, String qName,Attributes attributes) throws SAXException 
    //variable localName is the name of the tag

    //this function is called autiomatically when an end tag is encountered
    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
    }

    //this function gets called to return the value stored betweeen the closing and opening tags
    @Override
    public void characters(char[] ch, int start, int length) throws SAXException {
        //now variable value has the value stored between the closing and opening tags
        String value=new String(ch,start,length);
    }
}

Answer 2

1. Add java-json.jar in library folder
2. Compile files ('libs/java-json.jar') //add this line into your build

Here is the code to convert xml response to json response:

JSONObject jsonObj = null;
try {
        jsonObj = XML.toJSONObject(response.toString());
} catch (JSONException e) {
        Log.e("JSON exception", e.getMessage());
        e.printStackTrace();
}

Answer 3

for parse xml on android best way is to use SAXParser. i explained it bellow with demo....

first of all create your activity class like as bellw.

public class ActivityForSax extends ListActivity {
private ProgressDialog pDialog;
private ItemXMLHandler myXMLHandler;
private String rssFeed = "https://www.dropbox.com/s/t4o5wo6gdcnhgj8/imagelistview.xml?dl=1";
private TextView textview;
private ListView mListView;
private ArrayList<HashMap<String, String>> menuItems;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.xml_dom);

    textview = (TextView)findViewById(R.id.textView1);
    doParsing();

    mListView = getListView();
}

public void doParsing(){

    if (isNetworkAvailable()) {
        textview.setText("Loading...Please wait...");
        new AsyncData().execute(rssFeed);
    } else {
        showToast("No Network Connection!!!");
    }   
}
class AsyncData extends AsyncTask<String, Void, Void> {

    @Override
    protected void onPreExecute() {
        menuItems = new ArrayList<HashMap<String, String>>();
        pDialog = new ProgressDialog(ActivityForSax.this);
        pDialog.setTitle("Loading....");
        pDialog.setMessage("Please wait...");
        pDialog.show();
        super.onPreExecute();
    }

    @Override
    protected Void doInBackground(String... params) {

        try {
            SAXParserFactory spf = SAXParserFactory.newInstance();
            SAXParser sp = spf.newSAXParser();
            XMLReader xr = sp.getXMLReader();

            myXMLHandler = new ItemXMLHandler();
            xr.setContentHandler(myXMLHandler);

            URL _url = new URL(params[0]);

            xr.parse(new InputSource(_url.openStream()));

        } catch (ParserConfigurationException pce) {
            Log.e("SAX XML", "sax parse error", pce);
        } catch (SAXException se) {
            Log.e("SAX XML", "sax error", se);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;

    }

    @Override
    protected void onPostExecute(Void result) {
        super.onPostExecute(result);

        textview.setText("Done!!!");
        if (pDialog != null && pDialog.isShowing()) {
            pDialog.dismiss();
        }

        ArrayList<Bean> itemsList = myXMLHandler.getItemsList();

        for (int i = 0; i < itemsList.size(); i++) {
            Bean objBean = itemsList.get(i);
            // creating new HashMap
            HashMap<String, String> map = new HashMap<String, String>();
            // adding each child node to HashMap key => value
            map.put("TITLE :: ", objBean.getTitle());
            map.put("DESC :: ", objBean.getDesc());
            map.put("PUBDATE :: ", objBean.getPubDate());

            // adding HashList to ArrayList
            menuItems.add(map);
        }

        // Adding menuItems to ListView
        ListAdapter adapter = new SimpleAdapter(ActivityForSax.this, menuItems,
                R.layout.list_item,
                new String[] { "TITLE :: ", "DESC :: ", "PUBDATE :: " }, new int[] {
                R.id.name, R.id.email, R.id.mobile });

        mListView.setAdapter(adapter);

    }
}

public void showToast(String msg) {
    Toast.makeText(ActivityForSax.this, msg, Toast.LENGTH_LONG).show();
}

public boolean isNetworkAvailable() {
    ConnectivityManager connectivity = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
    if (connectivity == null) {
        return false;
    } else {
        NetworkInfo[] info = connectivity.getAllNetworkInfo();
        if (info != null) {
            for (int i = 0; i < info.length; i++) {
                if (info[i].getState() == NetworkInfo.State.CONNECTED) {
                    return true;
                }
            }
        }
    }
    return false;
}
}

now you need to create default handler class for parsing xml data.

public class ItemXMLHandler extends DefaultHandler {

Boolean currentElement = false;
String currentValue = "";
Bean item = null;
private ArrayList<Bean> itemsList = new ArrayList<Bean>();

public ArrayList<Bean> getItemsList() {
    return itemsList;
}

// Called when tag starts
@Override
public void startElement(String uri, String localName, String qName,
        Attributes attributes) throws SAXException {

    currentElement = true;
    currentValue = "";

    if (localName.equals("item")) {
        item = new Bean();
    }

}

// Called when tag closing
@Override
public void endElement(String uri, String localName, String qName)
        throws SAXException {

    currentElement = false;

    if (localName.equals("id")) {
        item.setId(currentValue);
    } else if (localName.equals("title")) {
        item.setTitle(currentValue);
    } else if (localName.equals("desc")) {
        item.setDesc(currentValue);
    } else if (localName.equals("pubDate")) {
        item.setPubDate(currentValue);
    } else if (localName.equals("link")) {
        item.setLink(currentValue);
    } else if (localName.equals("item")) {
        itemsList.add(item);
    }
}

// Called to get tag characters
@Override
public void characters(char[] ch, int start, int length)
        throws SAXException {

    if (currentElement) {
        currentValue = currentValue + new String(ch, start, length);
    }
}
}

and finally your Bean class like as...

public class Bean {

private String id;
private String title;
private String desc;
private String pubDate;
private String link;

public String getId() {
    return id;
}

public void setId(String id) {
    this.id = id;
}

public String getTitle() {
    return title;
}

public void setTitle(String title) {
    this.title = title;
}

public String getDesc() {
    return desc;
}

public void setDesc(String desc) {
    this.desc = desc;
}

public String getPubDate() {
    return pubDate;
}

public void setPubDate(String pubDate) {
    this.pubDate = pubDate;
}

public String getLink() {
    return link;
}

public void setLink(String link) {
    this.link = link;
}
}