JSON listview OnItemClickListener url (webview)

Question

I got all the data ... But I am not able to use webview url(UrlWeb) , i mean when i click on list item then it will open in web view. when i click any list it should pass corresponding url to the WebView activity.So how to achieve this, how to store corresponding url?? please someone help me..

My MainActivity :

public class MainActivity extends Activity {

ListView mListView;

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

    // URL to the JSON data         
    String strUrl = "http://www.mulnivasisangh.com/aman/listweb.json";

    // Creating a new non-ui thread task to download json data 
    DownloadTask downloadTask = new DownloadTask();

    // Starting the download process
    downloadTask.execute(strUrl);

    // Getting a reference to ListView of activity_main
    mListView = (ListView) findViewById(R.id.lv_countries);

    }

/** A method to download json data from url */
private String downloadUrl(String strUrl) throws IOException{
    String data = "";
    InputStream iStream = null;
    try{
            URL url = new URL(strUrl);

            // Creating an http connection to communicate with url 
            HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

            // Connecting to url 
            urlConnection.connect();

            // Reading data from url 
            iStream = urlConnection.getInputStream();

            BufferedReader br = new BufferedReader(new InputStreamReader(iStream));

            StringBuffer sb  = new StringBuffer();

            String line = "";
            while( ( line = br.readLine())  != null){
                sb.append(line);
            }

            data = sb.toString();

            br.close();

    }catch(Exception e){
            Log.d("Exception while downloading url", e.toString());
    }finally{
            iStream.close();
    }

    return data;
}



/** AsyncTask to download json data */
private class DownloadTask extends AsyncTask<String, Integer, String>{
    String data = null;
            @Override
            protected String doInBackground(String... url) {
                    try{
                        data = downloadUrl(url[0]);

                    }catch(Exception e){
                        Log.d("Background Task",e.toString());
                    }
                    return data;
            }

            @Override
            protected void onPostExecute(String result) {

                    // The parsing of the xml data is done in a non-ui thread 
                    ListViewLoaderTask listViewLoaderTask = new ListViewLoaderTask();

                    // Start parsing xml data
                    listViewLoaderTask.execute(result);                        

            }
}

/** AsyncTask to parse json data and load ListView */
private class ListViewLoaderTask extends AsyncTask<String, Void, SimpleAdapter>{

    JSONObject jObject;
    // Doing the parsing of xml data in a non-ui thread 
    @Override
    protected SimpleAdapter doInBackground(String... strJson) {
        try{
            jObject = new JSONObject(strJson[0]);
            CountryJSONParser countryJsonParser = new CountryJSONParser();
            countryJsonParser.parse(jObject);
        }catch(Exception e){
            Log.d("JSON Exception1",e.toString());
        }

        // Instantiating json parser class
        CountryJSONParser countryJsonParser = new CountryJSONParser();

        // A list object to store the parsed countries list
        List<HashMap<String, Object>> countries = null;

        try{
            // Getting the parsed data as a List construct
            countries = countryJsonParser.parse(jObject);
        }catch(Exception e){
            Log.d("Exception",e.toString());
        }          

        // Keys used in Hashmap 
        String[] from = { "country","flag","details", "URL"};

        // Ids of views in listview_layout
        int[] to = { R.id.tv_country,R.id.iv_flag,R.id.tv_country_details,R.id.tv_URL};

        // Instantiating an adapter to store each items
        // R.layout.listview_layout defines the layout of each item         
        SimpleAdapter adapter = new SimpleAdapter(getBaseContext(), countries, R.layout.lv_layout, from, to);  

        return adapter;
    }

    /** Invoked by the Android on "doInBackground" is executed */
    protected void onPostExecute(SimpleAdapter adapter) {

        // Setting adapter for the listview
        mListView.setAdapter(adapter);

        for(int i=0;i<adapter.getCount();i++){
            HashMap<String, Object> hm = (HashMap<String, Object>) adapter.getItem(i);
            String imgUrl = (String) hm.get("flag_path");
            ImageLoaderTask imageLoaderTask = new ImageLoaderTask();

            HashMap<String, Object> hmDownload = new HashMap<String, Object>();
            hm.put("flag_path",imgUrl);
            hm.put("position", i);

            // Starting ImageLoaderTask to download and populate image in the listview 
            imageLoaderTask.execute(hm);
        }

        mListView.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> arg0, View view, int arg2,
                    long arg3) {
                // TODO Auto-generated method stub
                        String URL = ((TextView) view.findViewById(R.id.tv_URL)).getText().toString();//this will take the value of the invincible textView
                        Intent i = new Intent(MainActivity.this, WebViewActivity.class);
                        i.putExtra("URL", URL);
                        startActivity(i); 
                      } 
});
    }
    }

/** AsyncTask to download and load an image in ListView */
private class ImageLoaderTask extends AsyncTask<HashMap<String, Object>, Void, HashMap<String, Object>>{

    @Override
    protected HashMap<String, Object> doInBackground(HashMap<String, Object>... hm) {

        InputStream iStream=null;
        String imgUrl = (String) hm[0].get("flag_path");
        int position = (Integer) hm[0].get("position");

        URL url;
        try {
            url = new URL(imgUrl);

            // Creating an http connection to communicate with url
            HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

            // Connecting to url                
            urlConnection.connect();

            // Reading data from url 
            iStream = urlConnection.getInputStream();

            // Getting Caching directory 
            File cacheDirectory = getBaseContext().getCacheDir();

            // Temporary file to store the downloaded image 
            File tmpFile = new File(cacheDirectory.getPath() + "/wpta_"+position+".png");               

            // The FileOutputStream to the temporary file
            FileOutputStream fOutStream = new FileOutputStream(tmpFile);

            // Creating a bitmap from the downloaded inputstream
            Bitmap b = BitmapFactory.decodeStream(iStream);             

            // Writing the bitmap to the temporary file as png file
            b.compress(Bitmap.CompressFormat.PNG,100, fOutStream);              

            // Flush the FileOutputStream
            fOutStream.flush();

            //Close the FileOutputStream
            fOutStream.close();             

            // Create a hashmap object to store image path and its position in the listview
            HashMap<String, Object> hmBitmap = new HashMap<String, Object>();

            // Storing the path to the temporary image file
            hmBitmap.put("flag",tmpFile.getPath());

            // Storing the position of the image in the listview
            hmBitmap.put("position",position);              

            // Returning the HashMap object containing the image path and position
            return hmBitmap;                


        }catch (Exception e) {              
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(HashMap<String, Object> result) {
        // Getting the path to the downloaded image
        String path = (String) result.get("flag");          

        // Getting the position of the downloaded image
        int position = (Integer) result.get("position");

        // Getting adapter of the listview
        SimpleAdapter adapter = (SimpleAdapter ) mListView.getAdapter();

        // Getting the hashmap object at the specified position of the listview
        HashMap<String, Object> hm = (HashMap<String, Object>) adapter.getItem(position);   

        // Overwriting the existing path in the adapter 
        hm.put("flag",path);

        // Noticing listview about the dataset changes
        adapter.notifyDataSetChanged(); 
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}

}

My CountryJSONParser :

public class CountryJSONParser {

// Receives a JSONObject and returns a list
public List<HashMap<String,Object>> parse(JSONObject jObject){      

    JSONArray jCountries = null;
    try {       
        // Retrieves all the elements in the 'countries' array 
        jCountries = jObject.getJSONArray("webs");
    } catch (JSONException e) {
        e.printStackTrace();
    }

     // Invoking getCountries with the array of json object
     // where each json object represent a country
    return getCountries(jCountries);
}


private List<HashMap<String, Object>> getCountries(JSONArray jCountries){
    int countryCount = jCountries.length();
    List<HashMap<String, Object>> countryList = new ArrayList<HashMap<String,Object>>();
    HashMap<String, Object> country = null; 

    // Taking each country, parses and adds to list object 
    for(int i=0; i<countryCount;i++){
        try {
            // Call getCountry with country JSON object to parse the country 
            country = getCountry((JSONObject)jCountries.get(i));
            countryList.add(country);

        } catch (JSONException e) {
            e.printStackTrace();
        }
    }
    return countryList;
}



// Parsing the Country JSON object 
private HashMap<String, Object> getCountry(JSONObject jCountry){

    HashMap<String, Object> country = new HashMap<String, Object>();
    String countryName = "";
    String flag="";
    String language = "";
    String capital = "";
    String web ="";


    try {
        countryName = jCountry.getString("Nom");
        flag = jCountry.getString("UrlImatge");
        language = jCountry.getString("Descripcio");
        capital = jCountry.getString("Id");
        web = jCountry.getString("UrlWeb");

        String details = "Descripcio : " + language + "\n" +
                "Id : " + capital + "\n" + "URL: " + web + "\n";

        country.put("country", countryName);
        country.put("UrlImatge", R.drawable.blank);
        country.put("flag_path", flag);
        country.put("details", details);
        country.put("URL", web);

    } catch (JSONException e) {         
        e.printStackTrace();
    }       
    return country;
}

}

Thanks in advance..

Answer 1

I use this trick when I want to pass data from listview to another activity.

1- I add a textView to my item-list.xml which is R.layout.lv_layout in your case and make its visibility gone. android:visibility="gone"

2- add the URL String to this textView, it wont be shown in the listview, because it has no visibility.

String[] from = { "country","flag","details", "URL"};

// Ids of views in listview_layout
int[] to = { R.id.tv_country,R.id.iv_flag,R.id.tv_country_details, R.id.tv_country_URL};//the forth one is the textView you set it as gone.

3- in OnItemClick function just add the following:

String URL = ((TextView) view.findViewById(R.id.tv_country_URL)).getText().toString();//this will take the value of the invincible textView
Intent i = new Intent(MainActivity.this, WebView.class);
i.putExtra("URL", URL);
startActivity(i);

4- use getIntent in your webView Activity to get the URL and load it.

if it is still vague please inform me. hope you got the idea.

Edit

you dont need getURL function anymore, I thought getCountries doesnt return a hashMap for URL. so all you have to do is create a invisible textView in your lv_layout and put each URL in it.

follow the 4 steps above.

for step 3 in Post:

protected void onPostExecute(SimpleAdapter adapter) {

    // Setting adapter for the listview
    mListView.setAdapter(adapter);

    for(int i=0;i<adapter.getCount();i++){
        HashMap<String, Object> hm = (HashMap<String, Object>) adapter.getItem(i);
        String imgUrl = (String) hm.get("flag_path");
        ImageLoaderTask imageLoaderTask = new ImageLoaderTask();

        HashMap<String, Object> hmDownload = new HashMap<String, Object>();
        hm.put("flag_path",imgUrl);
        hm.put("position", i);

        // Starting ImageLoaderTask to download and populate image in the listview 
        imageLoaderTask.execute(hm);
    }

    mListView.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> arg0, View view, int arg2,
                long arg3) {
            // TODO Auto-generated method stub
                            String URL = ((TextView) view.findViewById(R.id.tv_URL)).getText().toString();//this will take the value of the invincible textView
                    Intent i = new Intent(MainActivity.this, WebView.class);
                    i.putExtra("URL", URL);
                    startActivity(i); 
                  }      

Edit

for webViewActivity you need to get extra from the previous activity as the following:

public class WebViewActivity extends Activity{
private WebView webView;

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

    webView = (WebView) findViewById(R.id.webview);
    webView.setWebViewClient(new MyWebViewClient());


    String url = getIntent().getExtras().getString("URL")

    if (null != url) {
        webView.getSettings().setJavaScriptEnabled(true);
        webView.loadUrl(url);
    }
}

private class MyWebViewClient extends WebViewClient {
    @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        view.loadUrl(url);
        return true;
    }
}

}