I need public class FragmentB that extends ActionBarActivity. It has no errors, but when I try to call it in an adapter.
FragmentPagerAdapter code:
public class FragmentPagerAdapter extends android.support.v4.app.FragmentPagerAdapter{
private static int NUM_ITEMS = 3;
public FragmentPagerAdapter(FragmentManager fragmentManager) {
super(fragmentManager);
}
// Returns total number of pages
@Override
public int getCount() {
return NUM_ITEMS;
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
FragmentA a = new FragmentA();
return a;
case 1:
FragmentB b = new FragmentB();
return b;
case 2:
FragmentC c = new FragmentC();
return c;
default:
return null;
}
}
// Returns the page title for the top indicator
@Override
public CharSequence getPageTitle(int position) {
return "Page " + position;
}
}
It says that I need a class that extends android.support.v4.app.Fragment at return b. At Fragment A and C there is no implementation of ActionBarActivity, that is why there is no error, while in return b there is.
Basicly I need to show all the events on Fragment B. If I test it without the fragments it works, but with them it becomes a slight problem. I need the fragments because of the ViewPager for sliding.
Fragment B code:
private static final String TAG = FragmentB.class.getSimpleName();
private static final String url = "http://server.si/events.php";
private ProgressDialog pDialog;
private List<Event> eventList = new ArrayList<Event>();
private ListView listView;
private CustomListAdapter adapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
adapter = new CustomListAdapter(getActivity(), eventList);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_b, container, false);
ListView listView = (ListView) rootView.findViewById(R.id.list);
listView.setAdapter(adapter);
pDialog.setMessage("Loading Events...");
pDialog.show();
JsonArrayRequest eventReq = new JsonArrayRequest(url,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
Log.d(TAG, response.toString());
hidePDialog();
for (int i = 0; i < response.length(); i++) {
try {
JSONObject obj = response.getJSONObject(i);
Event event = new Event();
event.setTitle(obj.getString("name"));
event.setPicture_url(obj.getString("picture_url"));
event.setCity(obj.getString("city"));
event.setDate(obj.getString("date"));
eventList.add(event);
} catch (JSONException e) {
e.printStackTrace();
}
}
// notifying list adapter about data changes
// so that it renders the list view with updated data
adapter.notifyDataSetChanged();
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d(TAG, "Error: " + error.getMessage());
hidePDialog();
}
});
AppController.getInstance().addToRequestQueue(eventReq);
return rootView;
}
@Override
public void onDestroy() {
super.onDestroy();
hidePDialog();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
CustomListAdapter code: public class CustomListAdapter extends BaseAdapter { private Activity activity; private LayoutInflater inflater; private List eventItems; ImageLoader imageLoader = AppController.getInstance().getImageLoader(); public CustomListAdapter(Activity activity, List eventItems) { this.activity = activity; this.eventItems = eventItems; }
@Override
public int getCount() {
return eventItems.size();
}
@Override
public Object getItem(int location) {
return eventItems.get(location);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (inflater == null)
inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
if (convertView == null)
convertView = inflater.inflate(R.layout.list_row, null);
if (imageLoader == null)
imageLoader = AppController.getInstance().getImageLoader();
NetworkImageView thumbNail = (NetworkImageView) convertView
.findViewById(R.id.picture);
TextView name = (TextView) convertView.findViewById(R.id.name);
TextView city = (TextView) convertView.findViewById(R.id.city);
TextView date = (TextView) convertView.findViewById(R.id.date);
Event m = eventItems.get(position);
thumbNail.setImageUrl(m.getPicture_url(), imageLoader);
name.setText(m.getTitle());
city.setText("City: " + String.valueOf(m.getCity()));
date.setText(String.valueOf(m.getDate()));
return convertView;
}
This is the error at run:
java.lang.NullPointerException: Attempt to invoke virtual method 'com.android.volley.toolbox.ImageLoader teamtwo.event.com.events.Events.AppController.getImageLoader()' on a null object reference
at teamtwo.event.com.events.Events.CustomListAdapter.<init>(CustomListAdapter.java:27)
at teamtwo.event.com.events.FragmentB.onCreate(FragmentB.java:50)
Looks like, I'm doing something wrong with OnCreate methods. I don't know where should i put the code in. OnCreate is before everything inflates or creates both the activity and the fragment, while OnCreateView sets the fragment layout. I have no idea what to do.
