Fetching Data From Web Server using Sax Parsing

Question

I am fetching data from Web server using SAX parsing method all the data is shown in LogCat but not shown in my emulator

@SuppressLint("NewApi")
    public class IotdHandler extends DefaultHandler {
    private String url = "http://www.nasa.gov/rss/dyn/image_of_the_day.rss";
    private boolean inUrl = false;
    private boolean inTitle = false;
    private boolean inDescription = false;
    private boolean inItem = false;
    private boolean inDate = false;
    private static Bitmap image = null;
    private String imageUrl=null;
    private static String title = null;
    private static StringBuffer description = new StringBuffer();
    private static String date = null;

    public void processFeed() {
    try {
    //This part is added to allow the network connection on a main GUI thread...    
    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
    StrictMode.setThreadPolicy(policy); 
    SAXParserFactory factory = SAXParserFactory.newInstance();
    SAXParser parser = factory.newSAXParser();
    XMLReader reader = parser.getXMLReader();
    reader.setContentHandler(this);
    URL urlObj = new URL(url);
    InputStream inputStream = urlObj.openConnection().getInputStream();
    reader.parse(new InputSource(inputStream));
    } 
    catch (Exception e) 
    {
        e.printStackTrace();
        System.out.println(new String("Got Exception General"));
    }
    }

    private Bitmap getBitmap(String url) {
    try {
        System.out.println(url);
    HttpURLConnection connection =
    (HttpURLConnection)new URL(url).openConnection();
    connection.setDoInput(true);
    connection.connect();
    InputStream input = connection.getInputStream();
    Bitmap bitmap = BitmapFactory.decodeStream(input);
    input.close();
    return bitmap;
    } 
    catch (IOException ioe) 
    {
        System.out.println(new String("IOException in reading Image"));
        return null;
    }
    catch (Exception ioe) 
    {
        System.out.println(new String("IOException GENERAL"));
        return null;
    }
    }

    public void startElement(String uri, String localName, String qName,
    Attributes attributes) throws SAXException 
    {

    if (localName.equals("enclosure"))
    {
        System.out.println(new String("characters Image"));
        imageUrl = attributes.putValue("","url");
        System.out.println(imageUrl);
        inUrl = true; 
    }
    else { inUrl = false; }
    if (localName.startsWith("item")) { inItem = true; }
    else if (inItem) {
    if (localName.equals("title")) { inTitle = true; }
    else { inTitle = false; }
    if (localName.equals("description")) { inDescription = true; }
    else { inDescription = false; }
    if (localName.equals("pubDate")) { inDate = true; }
    else { inDate = false; }
    }
    }

    public void characters(char ch[], int start, int length) {
        System.out.println(new String("characters"));
    String chars = new String(ch).substring(start, start + length);
    System.out.println(chars);
    if (inUrl && image == null) 
    {
        System.out.println(new String("IMAGE"));
        System.out.println(imageUrl);
        image = getBitmap(imageUrl);
    }
    if (inTitle && title == null) {
        System.out.println(new String("TITLE"));
        title = chars; }
    if (inDescription) { description.append(chars); }
    if (inDate && date == null) { date = chars; }
    }

    public static Bitmap getImage() { return image; }
    public static String getTitle() { return title; }
    public static StringBuffer getDescription() { return description; }
    public static String getDate() { return date; }

    }

---

This is my MainActivity class I am trying to fetch the data from nasa rss feed all the data is shown in the logcat but not displayed in the emulator

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        IotdHandler handler = new IotdHandler(); //create handler
        handler.processFeed(); //start parsing
       resetDisplay(IotdHandler.getTitle(), IotdHandler.getDate(),
                IotdHandler.getImage(), IotdHandler.getDescription());
    }



    private void resetDisplay(String title, String date, Bitmap image, StringBuffer description)
    {
        TextView titleView = (TextView)findViewById(R.id.imageTitle);
        titleView.setText(title);

        TextView dateView = (TextView)findViewById(R.id.imageDate);
        dateView.setText(date);

        ImageView imageView = (ImageView)findViewById(R.id.imageDisplay);

        imageView.setImageBitmap(image);

        TextView descriptionView = (TextView)findViewById(R.id.imageDescription);
        descriptionView.setText(description);

    }
    }

Answer 1

A class containing the properties:

public class ImageDetails {
    private String imageDate, imageTitle, imageDesc;
    // getters and setters here
}

inside the IOHandler class, inside the startElement function, add this,

if(qName.equalsIgnoreCase("channel") {
    imageDetails = new ImageDetails();
    // make sure imageDetails is declared in the class
}

this line instantiates the imgedetails class when the start tag channel is found, and it would be intantiated just once since the feed has only one item.

other changes to be made in the IOHandler class

create a function like

public ImageDetails getImageDetails() {
    // call the function that reads the documents or parses it
    return imageDetails;
}

Whenever the localnames match use the setter methods to set the values.

Create an instance of IOHandler in the activity class

IOHandler ioHandler = new IOHandler(pass values if needed);
ImageDetails imageDetails = ioHandler.getImageDetails();

use imageDetails.getter methods to fill the textviews with data.

======== EDIT #1

change the startElement function to this:

 @Override
public void startElement(String uri, String localName, String qName,
        org.xml.sax.Attributes attributes) throws SAXException {
    super.startElement(uri, localName, qName, attributes);

     if (qName.equals("enclosure"))
        {
            System.out.println(new String("characters Image"));
            //imageUrl = attributes.putValue("","url");
            // I have commented out this line, try to figure out how to get this atleast
            System.out.println(imageUrl);
            inUrl = true; 
        }
        else { inUrl = false; }
        if (qName.startsWith("item")) { inItem = true; }
        else if (inItem) {
        if (qName.equals("title")) { inTitle = true; }
        else { inTitle = false; }
        if (qName.equals("description")) { inDescription = true; }
        else { inDescription = false; }
        if (qName.equals("pubDate")) { inDate = true; }
        else { inDate = false; }
        }
        }

}

Hope this helps.