asked on

JSON Parser in listview in ListFragment

Is it possible to have a JSON Parser inside a ListFragment?

I've searched the web for hours. When I run my app, and click on the tab to view the list view, the app crashes.

public class FragmentsTab3 extends ListFragment implements ActionBar.TabListener {
...
JSONParser jParser = new JSONParser();
	        
	        //getting JSON string from URL
	        posts = jParser.getJSONFromUrlToArray(url);

for(int i = 0; i < posts.length(); i++){                        
				    HashMap<String, String> map = new HashMap<String, String>();    
				    JSONObject e = posts.getJSONObject(i);

				    map.put(TAG_TITLE, e.getString(TAG_TITLE));
				    map.put(TAG_VIEWS, e.getString(TAG_VIEWS) + " views");
				    
				    levelList.add(map);            
				}

Open in new window

My code works fine on a Activity or ListActivity

ASKER CERTIFIED SOLUTION

Dejan Pažin

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girionis

When I run my app, and click on the tab to view the list view, the app crashes.

What is the error?

BTMExpert

ASKER

05-16 11:48:48.514: E/AndroidRuntime(801): FATAL EXCEPTION: AsyncTask #1
05-16 11:48:48.514: E/AndroidRuntime(801): java.lang.RuntimeException: An error occured while executing doInBackground()
05-16 11:48:48.514: E/AndroidRuntime(801):       at android.os.AsyncTask$3.done(AsyncTask.java:299)
05-16 11:48:48.514: E/AndroidRuntime(801):       at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
05-16 11:48:48.514: E/AndroidRuntime(801):       at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
05-16 11:48:48.514: E/AndroidRuntime(801):       at java.util.concurrent.FutureTask.run(FutureTask.java:239)
05-16 11:48:48.514: E/AndroidRuntime(801):       at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
05-16 11:48:48.514: E/AndroidRuntime(801):       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
05-16 11:48:48.514: E/AndroidRuntime(801):       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
05-16 11:48:48.514: E/AndroidRuntime(801):       at java.lang.Thread.run(Thread.java:856)
05-16 11:48:48.514: E/AndroidRuntime(801): Caused by: java.lang.IllegalStateException: Fragment FragmentsTab3{40dae140} not attached to Activity
05-16 11:48:48.514: E/AndroidRuntime(801):       at android.app.Fragment.getResources(Fragment.java:762)
05-16 11:48:48.514: E/AndroidRuntime(801):       at com.androidbegin.fragmenttabs.FragmentsTab3$MyAsyncTask.doInBackground(FragmentsTab3.java:94)
05-16 11:48:48.514: E/AndroidRuntime(801):       at com.androidbegin.fragmenttabs.FragmentsTab3$MyAsyncTask.doInBackground(FragmentsTab3.java:1)
05-16 11:48:48.514: E/AndroidRuntime(801):       at android.os.AsyncTask$2.call(AsyncTask.java:287)
05-16 11:48:48.514: E/AndroidRuntime(801):       at java.util.concurrent.FutureTask.run(FutureTask.java:234)
05-16 11:48:48.514: E/AndroidRuntime(801):       ... 4 more
05-16 11:48:52.913: D/dalvikvm(801): GC_CONCURRENT freed 413K, 14% free 3509K/4052K, paused 4ms+7ms, total 65ms
05-16 11:48:52.943: D/dalvikvm(801): WAIT_FOR_CONCURRENT_GC blocked 64ms

BTMExpert

ASKER

Here's where I try to parse the JSON url

@Override
	    protected ArrayList<HashMap<String, String>>doInBackground(String... params) {

	        //Creating JSON Parser instance
	        JSONParser jParser = new JSONParser();
	        
	        //getting JSON string from URL
	     // Making HTTP request
			try {
				// defaultHttpClient
				DefaultHttpClient httpClient = new DefaultHttpClient();
				HttpGet httpGet = new HttpGet(url);

				HttpResponse httpResponse = httpClient.execute(httpGet);
				HttpEntity httpEntity = httpResponse.getEntity();
				is = httpEntity.getContent();			

			} catch (UnsupportedEncodingException e) {
				e.printStackTrace();
			} catch (ClientProtocolException e) {
				e.printStackTrace();
			} catch (IOException e) {
				e.printStackTrace();
			}
			
			try {
				BufferedReader reader = new BufferedReader(new InputStreamReader(
						is, "iso-8859-1"), 8);
				StringBuilder sb = new StringBuilder();
				String line = null;
				while ((line = reader.readLine()) != null) {
					sb.append(line + "\n");
				}
				is.close();
				json = sb.toString();
			} catch (Exception e) {
				Log.e("Buffer Error", "Error converting result " + e.toString());
			}

			// try parse the string to a JSON object
			try {
				post = new JSONArray(json);
			} catch (JSONException e) {
				Log.e("JSON Parser", "Error parsing data " + e.toString());
			}
	       
	        String[] adobe_products = getResources().getStringArray(R.array.adobe_products);
	        
	        for(int i = 0; i < adobe_products.length; i++){                        
			    HashMap<String, String> map = new HashMap<String, String>();    

			    map.put(TAG_TITLE, adobe_products[i]);
			    
			    levelList.add(map);            
			}
	        

	        return levelList;

	    }

Open in new window

BTMExpert

ASKER

here's where I got most of my code from

http://www.androidhive.info/2012/01/android-json-parsing-tutorial/

Dejan Pažin

It doesnt look like JSON error - it states that you have a problem with a Fragment:

.... Fragment FragmentsTab3{40dae140} not attached to Activity....

Can you post the complete code?

girionis

Have a look here for a possible solution.

BTMExpert

ASKER

public class FragmentsTab3 extends ListFragment implements ActionBar.TabListener {

	private Fragment mFragment;
	//YouTube
	private static final String TAG_TITLE = "title";
	private static final String TAG_VIEWS = "views";
	//JSON Node names (level, sensorID, value)
	//pspace JSONArray

	private static String url = "secret url but just a basic json format like twitter";
	JSONArray posts = null;
	
	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
		return inflater.inflate(R.layout.fragment3, container, false);
	}
	public void onStart() {
        super.onStart();
        new MyAsyncTask().execute();
	}

	class MyAsyncTask extends AsyncTask<String, Integer, ArrayList<HashMap<String, String>> > {

	    //Hashmap for ListView
	    ArrayList<HashMap<String, String>> levelList = new ArrayList<HashMap<String, String>>();

	    @Override
	    protected ArrayList<HashMap<String, String>>doInBackground(String... params) {

	        //Creating JSON Parser instance
	        JSONParser jParser = new JSONParser();
	        
	        try {
				// Getting Array
				posts = jParser.getJSONFromUrlToArray(url);
			
				for(int i = 0; i < posts.length(); i++){                        
				    HashMap<String, String> map = new HashMap<String, String>();    
				    JSONObject e = posts.getJSONObject(i);

				    map.put(TAG_TITLE, e.getString(TAG_TITLE));
				    map.put(TAG_VIEWS, e.getString(TAG_VIEWS) + " views");
				    
				    levelList.add(map);            
				}
				
		
			} catch (JSONException e) {
				e.printStackTrace();
			}
	        return levelList;

	    }

	    @Override
	    protected void onPostExecute(ArrayList<HashMap<String, String>> levelList) {

	        ListAdapter adapter = new SimpleAdapter(getActivity(), levelList, R.layout.youtube_list, new String[] { TAG_TITLE }, new int[] {
				R.id.title });
	        setListAdapter(adapter);

	    }

	}

	
	public void onTabSelected(Tab tab, FragmentTransaction ft) {
		// TODO Auto-generated method stub
		mFragment = new FragmentsTab3();
		// Attach fragment3.xml layout
		ft.add(android.R.id.content, mFragment);
		ft.attach(mFragment);
	}

	public void onTabUnselected(Tab tab, FragmentTransaction ft) {
		// TODO Auto-generated method stub
		// Remove fragment3.xml layout
		ft.remove(mFragment);
	}

	public void onTabReselected(Tab tab, FragmentTransaction ft) {
		// TODO Auto-generated method stub

	}

	@Override
	public void onActivityCreated(Bundle savedInstanceState) {
		super.onActivityCreated(savedInstanceState);

		
		
	}

	public void onListItemClick(ListView l, View v, int position, long id) {
		// Do something with the data

	}
}

Open in new window

I have a JSONParser class with this function in it

public JSONArray getJSONFromUrlToArray(String url) {

		
		// Making HTTP request
		try {
			// defaultHttpClient
			DefaultHttpClient httpClient = new DefaultHttpClient();
			HttpGet httpGet = new HttpGet(url);

			HttpResponse httpResponse = httpClient.execute(httpGet);
			HttpEntity httpEntity = httpResponse.getEntity();
			is = httpEntity.getContent();			

		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		} catch (ClientProtocolException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		try {
			BufferedReader reader = new BufferedReader(new InputStreamReader(
					is, "iso-8859-1"), 8);
			StringBuilder sb = new StringBuilder();
			String line = null;
			while ((line = reader.readLine()) != null) {
				sb.append(line + "\n");
			}
			is.close();
			json = sb.toString();
		} catch (Exception e) {
			Log.e("Buffer Error", "Error converting result " + e.toString());
		}

		// try parse the string to a JSON object
		try {
			jObjA = new JSONArray(json);
		} catch (JSONException e) {
			Log.e("JSON Parser", "Error parsing data " + e.toString());
		}
		// return JSON String
		return jObjA;

	}

Open in new window

BTMExpert

ASKER

I still get an error. I tried to start over with the slide tab template and I still get the same crashing and error. Is there an example of a listfragment and json that works? If I use a static array for my listview it works fine. If i use json on a list activity it works fine. list fragment crashes.

BTMExpert

ASKER

05-16 20:27:14.926: E/AndroidRuntime(6511): FATAL EXCEPTION: main
05-16 20:27:14.926: E/AndroidRuntime(6511): android.os.NetworkOnMainThreadException
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at java.net.InetAddress.getAllByName(InetAddress.java:214)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at com.example.stupidandroids.JSONParser.getJSONFromUrlToArray(JSONParser.java:88)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at com.example.stupidandroids.Videos.onCreateView(Videos.java:44)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:461)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.view.ViewPager.populate(ViewPager.java:1064)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.view.ViewPager.populate(ViewPager.java:911)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1432)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.View.measure(View.java:15518)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.View.measure(View.java:15518)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.widget.LinearLayout.measureVertical(LinearLayout.java:847)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.View.measure(View.java:15518)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2176)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.View.measure(View.java:15518)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1874)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1089)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1265)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:989)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4351)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.Choreographer.doCallbacks(Choreographer.java:562)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.Choreographer.doFrame(Choreographer.java:532)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.os.Handler.handleCallback(Handler.java:725)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.os.Handler.dispatchMessage(Handler.java:92)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.os.Looper.loop(Looper.java:137)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at android.app.ActivityThread.main(ActivityThread.java:5041)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at java.lang.reflect.Method.invokeNative(Native Method)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at java.lang.reflect.Method.invoke(Method.java:511)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-16 20:27:14.926: E/AndroidRuntime(6511):       at dalvik.system.NativeStart.main(Native Method)

Anyone?

girionis

Can you post your full code?

BTMExpert

ASKER

Main.java

import java.util.Locale;

import android.app.ActionBar;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.NavUtils;
import android.support.v4.view.ViewPager;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class MainActivity extends FragmentActivity implements
		ActionBar.TabListener {

	/**
	 * The {@link android.support.v4.view.PagerAdapter} that will provide
	 * fragments for each of the sections. We use a
	 * {@link android.support.v4.app.FragmentPagerAdapter} derivative, which
	 * will keep every loaded fragment in memory. If this becomes too memory
	 * intensive, it may be best to switch to a
	 * {@link android.support.v4.app.FragmentStatePagerAdapter}.
	 */
	SectionsPagerAdapter mSectionsPagerAdapter;

	/**
	 * The {@link ViewPager} that will host the section contents.
	 */
	ViewPager mViewPager;

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

		// Set up the action bar.
		final ActionBar actionBar = getActionBar();
		actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

		// Hide Actionbar Icon
		actionBar.setDisplayShowHomeEnabled(false);

		// Hide Actionbar Title
		actionBar.setDisplayShowTitleEnabled(false);

		// Create the adapter that will return a fragment for each of the three
		// primary sections of the app.
		mSectionsPagerAdapter = new SectionsPagerAdapter(
				getSupportFragmentManager());

		// Set up the ViewPager with the sections adapter.
		mViewPager = (ViewPager) findViewById(R.id.pager);
		mViewPager.setAdapter(mSectionsPagerAdapter);

		// When swiping between different sections, select the corresponding
		// tab. We can also use ActionBar.Tab#select() to do this if we have
		// a reference to the Tab.
		mViewPager
				.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
					@Override
					public void onPageSelected(int position) {
						actionBar.setSelectedNavigationItem(position);
					}
				});

		// Create first Tab
		actionBar.addTab(actionBar.newTab()
				.setText("Videos")
				.setTabListener(this));

		// For each of the sections in the app, add a tab to the action bar.
		for (int i = 1; i < mSectionsPagerAdapter.getCount(); i++) {
			// Create a tab with text corresponding to the page title defined by
			// the adapter. Also specify this Activity object, which implements
			// the TabListener interface, as the callback (listener) for when
			// this tab is selected.
			actionBar.addTab(actionBar.newTab()
					.setText(mSectionsPagerAdapter.getPageTitle(i))
					.setTabListener(this));
		}

	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

	@Override
	public void onTabSelected(ActionBar.Tab tab,
			FragmentTransaction fragmentTransaction) {
		// When the given tab is selected, switch to the corresponding page in
		// the ViewPager.
		mViewPager.setCurrentItem(tab.getPosition());
	}

	@Override
	public void onTabUnselected(ActionBar.Tab tab,
			FragmentTransaction fragmentTransaction) {
	}

	@Override
	public void onTabReselected(ActionBar.Tab tab,
			FragmentTransaction fragmentTransaction) {
	}

	/**
	 * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
	 * one of the sections/tabs/pages.
	 */
	public class SectionsPagerAdapter extends FragmentPagerAdapter {

		public SectionsPagerAdapter(FragmentManager fm) {
			super(fm);
		}

		@Override
		public Fragment getItem(int position) {
			// getItem is called to instantiate the fragment for the given page.
			// Return a DummySectionFragment (defined as a static inner class
			// below) with the page number as its lone argument.
			if(position > 0) {
			System.out.println(position);
			Fragment fragment = new DummySectionFragment();
			Bundle args = new Bundle();
			args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, position + 1);
			fragment.setArguments(args);
			
			return fragment;
			} else {
				Fragment fragment = new Videos();
				return fragment;
			}
		}

		@Override
		public int getCount() {
			// Show 3 total pages.
			return 3;
		}

		@Override
		public CharSequence getPageTitle(int position) {
			Locale l = Locale.getDefault();
			switch (position) {
			case 0:
				return getString(R.string.title_section1).toUpperCase(l);
			case 1:
				return getString(R.string.title_section2).toUpperCase(l);
			case 2:
				return getString(R.string.title_section3).toUpperCase(l);
			case 3:
				return getString(R.string.title_section4).toUpperCase(l);
			case 4:
				return getString(R.string.title_section5).toUpperCase(l);
			}

			return null;
		}
	}

	/**
	 * A dummy fragment representing a section of the app, but that simply
	 * displays dummy text.
	 */
	public static class DummySectionFragment extends Fragment {
		/**
		 * The fragment argument representing the section number for this
		 * fragment.
		 */
		public static final String ARG_SECTION_NUMBER = "section_number";

		public DummySectionFragment() {
		}

		@Override
		public View onCreateView(LayoutInflater inflater, ViewGroup container,
				Bundle savedInstanceState) {
			View rootView = inflater.inflate(R.layout.fragment_main_dummy,
					container, false);
			TextView dummyTextView = (TextView) rootView
					.findViewById(R.id.section_label);
			dummyTextView.setText(Integer.toString(getArguments().getInt(
					ARG_SECTION_NUMBER)));
			return rootView;
		}
	}
	
	

}

Open in new window

JSONParser.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
 
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONArray;


import android.util.Log;

public class JSONParser {

	static InputStream is = null;
	static JSONObject jObj = null;
	static JSONArray jObjA = null;
	static String json = "";

	// constructor
	public JSONParser() {

	}

public JSONObject getJSONFromUrl(String url) {
        
        // Making HTTP request
        try {
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
 
            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();            
 
        } catch (UnsupportedEncodingException exception) {
            exception.printStackTrace();
        } catch (ClientProtocolException exception) {
            exception.printStackTrace();
        } catch (IOException exception) {
            exception.printStackTrace();
        }
        
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "iso-8859-1"), 8);
            StringBuilder sBuilder = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sBuilder.append(line + "\n");
            }
            is.close();
            json = sBuilder.toString();
        } catch (Exception exception) {
            exception.printStackTrace();
        }
 
        // Parsing the string to a JSON object
        try {
        	jObj = new JSONObject(json);
        } catch (JSONException exception) {
            exception.printStackTrace();
        }
 
        // JSON String
        return jObj;
 
    }

	public JSONObject getJSONFromUrlToObject(String url) {

		// Making HTTP request
		try {
			// defaultHttpClient
			DefaultHttpClient httpClient = new DefaultHttpClient();
			HttpPost httpPost = new HttpPost(url);

			HttpResponse httpResponse = httpClient.execute(httpPost);
			HttpEntity httpEntity = httpResponse.getEntity();
			is = httpEntity.getContent();			

		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		} catch (ClientProtocolException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		try {
			BufferedReader reader = new BufferedReader(new InputStreamReader(
					is, "iso-8859-1"), 8);
			StringBuilder sb = new StringBuilder();
			String line = null;
			while ((line = reader.readLine()) != null) {
				sb.append(line + "\n");
			}
			is.close();
			json = sb.toString();
		} catch (Exception e) {
			Log.e("Buffer Error", "Error converting result " + e.toString());
		}

		// try parse the string to a JSON object
		try {
			jObj = new JSONObject(json);
		} catch (JSONException e) {
			Log.e("JSON Parser", "Error parsing data " + e.toString());
		}

		// return JSON String
		return jObj;

	}
	
	public JSONArray getJSONFromUrlToArray(String url) {

		
		// Making HTTP request
		try {
			// defaultHttpClient
			DefaultHttpClient httpClient = new DefaultHttpClient();
			HttpGet httpGet = new HttpGet(url);

			HttpResponse httpResponse = httpClient.execute(httpGet);
			HttpEntity httpEntity = httpResponse.getEntity();
			is = httpEntity.getContent();			

		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		} catch (ClientProtocolException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		try {
			BufferedReader reader = new BufferedReader(new InputStreamReader(
					is, "iso-8859-1"), 8);
			StringBuilder sb = new StringBuilder();
			String line = null;
			while ((line = reader.readLine()) != null) {
				sb.append(line + "\n");
			}
			is.close();
			json = sb.toString();
		} catch (Exception e) {
			Log.e("Buffer Error", "Error converting result " + e.toString());
		}

		// try parse the string to a JSON object
		try {
			jObjA = new JSONArray(json);
		} catch (JSONException e) {
			Log.e("JSON Parser", "Error parsing data " + e.toString());
		}
		// return JSON String
		return jObjA;

	}
	
	
}

Open in new window

Videos.java

import java.util.ArrayList;
import java.util.HashMap;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.support.v4.app.Fragment;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class Videos extends Fragment {
	/**
	 * The fragment argument representing the section number for this
	 * fragment.
	 */
	private static final String TAG_TITLE = "title";
	private static final String TAG_VIEWS = "views";
	private ArrayList<HashMap<String, Object>> filterListData;
    private ListView filterListView;
	private static String url = "json formatted webpage like twitter";
	JSONArray posts = null;
	private ArrayList<HashMap<String, String>> levelList = new ArrayList<HashMap<String, String>>();

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
			Bundle savedInstanceState) {
		View rootView = inflater.inflate(R.layout.video_list,
				container, false);

		filterListView = (ListView) rootView.findViewById(R.id.list);
		new LoadJsonTask().execute(url);

		return rootView;
	}
	
	private class LoadJsonTask extends AsyncTask<String, Void, ArrayList<HashMap<String, String>> > {
	       protected ArrayList<HashMap<String, String>> doInBackground (String... params){
	           return doGetJson(params[0]);
	       }


	    @Override
	    protected void onPostExecute(ArrayList<HashMap<String, String>> levelList) {
	    	if(isAdded()){
	            getResources().getString(R.string.app_name);
	            ListAdapter adapter = new SimpleAdapter(getActivity(), levelList, R.layout.youtube_list, new String[] { TAG_TITLE, TAG_VIEWS }, new int[] {
					R.id.title, R.id.views });
	            filterListView.setAdapter(adapter);
	        }
	        

	    }

	}
	
	public ArrayList<HashMap<String, String>> doGetJson(String url) {
		JSONParser jParser = new JSONParser();
        
		try {
			// Getting Array
			posts = jParser.getJSONFromUrlToArray(url);
			
			for(int i = 0; i < posts.length(); i++){                        
			    HashMap<String, String> map = new HashMap<String, String>();    
			    JSONObject e = posts.getJSONObject(i);

			    map.put(TAG_TITLE, e.getString(TAG_TITLE));
			    map.put(TAG_VIEWS, e.getString(TAG_VIEWS) + " views");
			    
			    levelList.add(map);            
			}
			
	
		} catch (JSONException e) {
			e.printStackTrace();
		}
		
		return levelList;
	
	}
}

Open in new window

Dejan Pažin

We're also gonna need the xml files.

BTMExpert

ASKER

I got it working now