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I have implemented a Custom List View which displays text along with image. The List View fetches data from XML data present over the internet. When the user scrolls down, more data is loaded into the application. Now, I am trying to include a search bar so that when the user searches for some data, the application displays the results returned by the search. The main problem is that the list view doesn't show the correct data when search is performed.

When I check the URL that is being executed by the Search bar in a browser, it shows the correct results, but in Android application it behaves differently.

Below is the code of my Activity that performs this whole work:-

public class OrganizationActivity extends Activity implements OnScrollListener {

int itemsPerPage = 10;
boolean loadingMore = false;
int mPos=0;

// All static variables
static final String URL = "some URL";
static int page_no = 1;

// XML node keys
static final String KEY_ORGANIZATION = "organization"; // parent node
static final String KEY_ID = "id";
static final String KEY_NAME = "name";
static final String KEY_CITY = "city";
static final String KEY_STATE = "state";
static final String KEY_IMAGE_URL = "image";

ListView list;
LazyAdapter adapter;
ArrayList<HashMap<String, String>> orgsList = new ArrayList<HashMap<String, String>>();
private EditText filterText = null;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.main);

    filterText = (EditText) findViewById(R.id.search_box_et);
    filterText.addTextChangedListener(new TextWatcher() 
    {
        @Override
        public void afterTextChanged(Editable arg0) {
            // TODO Auto-generated method stub
        }

        @Override
        public void beforeTextChanged(CharSequence arg0, int arg1,
                int arg2, int arg3) {
            // TODO Auto-generated method stub
        }

        @Override
        public void onTextChanged(CharSequence arg0, int arg1, int arg2,
                int arg3) {
            // TODO Auto-generated method stub
            if(arg0.length()==0)
            {
                list.setAdapter(new LazyAdapter(OrganizationActivity.this, orgsList));
            }
            list.setAdapter(new LazyAdapter(OrganizationActivity.this, orgsList));
            String searchtext = null;
            try {
                searchtext=URLEncoder.encode(arg0.toString().trim(),"UTF-8");
            } catch (UnsupportedEncodingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            String urlStr = "myURL?search="+searchtext;
            new LoadData().execute(urlStr);
            adapter = new LazyAdapter(OrganizationActivity.this, orgsList);
            list.setAdapter(adapter);
        }

    });

    XMLParser parser = new XMLParser();
    String xml = parser.getXmlFromUrl(URL); // getting XML from URL
    Document doc = parser.getDomElement(xml); // getting DOM element

    NodeList nl = doc.getElementsByTagName(KEY_ORGANIZATION);
    // looping through all organization nodes <organization>
    for (int i = 0; i < nl.getLength(); i++) {
        // creating new HashMap
        HashMap<String, String> map = new HashMap<String, String>();
        Element e = (Element) nl.item(i);
        // adding each child node to HashMap key => value
        map.put(KEY_ID, parser.getValue(e, KEY_ID));
        map.put(KEY_NAME, parser.getValue(e, KEY_NAME));
        map.put(KEY_CITY, parser.getValue(e, KEY_CITY));
        map.put(KEY_STATE, parser.getValue(e, KEY_STATE));
        map.put(KEY_IMAGE_URL, parser.getValue(e, KEY_IMAGE_URL));

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

    list = (ListView) findViewById(R.id.list);

    View footerView = ((LayoutInflater) this
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(
            R.layout.listfooter, null, false);
    list.addFooterView(footerView);

    // Getting adapter by passing xml data ArrayList
    adapter = new LazyAdapter(this, orgsList);
    list.setAdapter(adapter);
    list.setOnScrollListener(this);

    // Click event for single list row
    list.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {

            String name = orgsList.get(position).get(KEY_NAME).toString();
            Toast.makeText(getApplicationContext(), name, Toast.LENGTH_LONG)
                    .show();
        }
    });

}


private class LoadData extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... urls) {

        for (String url : urls) {
            // TODO Auto-generated method stub
            XMLParser parser = new XMLParser();
            String xml = parser.getXmlFromUrl(url); // getting XML from URL
            Document doc = parser.getDomElement(xml); // getting DOM element

            NodeList nl = doc.getElementsByTagName(KEY_ORGANIZATION);
            // looping through all organization nodes <organization>
            for (int i = 0; i < nl.getLength(); i++) {
                // creating new HashMap
                HashMap<String, String> map = new HashMap<String, String>();
                Element e = (Element) nl.item(i);
                // adding each child node to HashMap key => value
                map.put(KEY_ID, parser.getValue(e, KEY_ID));
                map.put(KEY_NAME, parser.getValue(e, KEY_NAME));
                map.put(KEY_CITY, parser.getValue(e, KEY_CITY));
                map.put(KEY_STATE, parser.getValue(e, KEY_STATE));
                map.put(KEY_IMAGE_URL, parser.getValue(e, KEY_IMAGE_URL));

                // adding HashList to ArrayList
                orgsList.add(map);
            }
        }
        return null;
    }

    @Override
    protected void onPostExecute(String result) {
        // TODO Auto-generated method stub
        adapter = new LazyAdapter(OrganizationActivity.this, orgsList);
        list.setAdapter(adapter);
        list.setSelectionFromTop(mPos, 0);
    }
}

@Override
public void onScroll(AbsListView view, int firstVisibleItem,
        int visibleItemCount, int totalItemCount) {

    //Get the visible item position
    mPos=list.getFirstVisiblePosition();

    int lastInScreen = firstVisibleItem + visibleItemCount;

    //Is the bottom item visible & not loading more already? Load more !
    if ((lastInScreen == totalItemCount) && !(loadingMore)) {
        page_no++;
        String pageURL = "myURL?page="
                + page_no;
        new LoadData().execute(pageURL);
    }

}

@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
    // TODO Auto-generated method stub

}

}

Please help me out in finding the solution to this problem...

Shekhar Chikara
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  • What do you mean by 'doesn't show the correct data'? – code-jaff Aug 09 '12 at 06:32
  • 2
    It shows the previous data loaded in the list view and the data returned by the search query... – Shekhar Chikara Aug 09 '12 at 06:35
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    @ShekharChikara Read this post to search `custom List` http://android-helper.blogspot.in/2011/03/android-search-in-listview-example.html – Akshay Aug 09 '12 at 06:38
  • 2
    Please read the following article carefully, it will be more helpful to you: [Android custom listview with Image and Text/](http://www.androidhive.info/2012/02/android-custom-listview-with-image-and-text/) – ckpatel Aug 09 '12 at 06:36

1 Answers1

0

Looks like I was doing little bit of mistake in refreshing my ListView with the new data and also I was calling the notifyDataSetListener somewhere else. Now it is working absolutely fine..

Shekhar Chikara
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