RecyclerView in fragment crash after start

Question

please help . i have used RecycleView in fragment . but when i start the activity... get crash! i think caused from view . but dont know why !? anybody have idea? Hi .please help . i have used RecycleView in fragment . but when i start the activity... get crash! i think caused from view . but dont know why !? anybody have idea?

fragmentHome.java

public class HomeFragment2 extends Fragment {

List<DataAdapter> ListOfdataAdapter;
RecyclerView recyclerView;
String HTTP_JSON_URL = "http://androidblog.esy.es/ImageJsonData.php";
String Image_Name_JSON = "image_title";
String Image_URL_JSON = "image_url";
JsonArrayRequest RequestOfJSonArray ;
RequestQueue requestQueue ;
View view ;
int RecyclerViewItemPosition ;
RecyclerView.LayoutManager layoutManagerOfrecyclerView;
RecyclerView.Adapter recyclerViewadapter;
ArrayList<String> ImageTitleNameArrayListForClick;


public static HomeFragment2 newInstance() {


    return new HomeFragment2();
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {

    View v = inflater.inflate(R.layout.fragment_home2, container, false);

    ImageTitleNameArrayListForClick = new ArrayList<>();

    ListOfdataAdapter = new ArrayList<>();

    recyclerView =getActivity(). findViewById(R.id.recyclerview1);

    recyclerView.setHasFixedSize(true);

    layoutManagerOfrecyclerView = new LinearLayoutManager(getActivity());

    recyclerView.setLayoutManager(layoutManagerOfrecyclerView);

    JSON_HTTP_CALL();

    // Implementing Click Listener on RecyclerView.
    recyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() {

        GestureDetector gestureDetector = new GestureDetector(getActivity(), new GestureDetector.SimpleOnGestureListener() {

            @Override public boolean onSingleTapUp(MotionEvent motionEvent) {

                return true;
            }

        });
        @Override
        public boolean onInterceptTouchEvent(RecyclerView Recyclerview, MotionEvent motionEvent) {

            view = Recyclerview.findChildViewUnder(motionEvent.getX(), motionEvent.getY());

            if(view != null && gestureDetector.onTouchEvent(motionEvent)) {

                //Getting RecyclerView Clicked Item value.
                RecyclerViewItemPosition = Recyclerview.getChildAdapterPosition(view);

                // Showing RecyclerView Clicked Item value using Toast.
                Toast.makeText(getActivity(), ImageTitleNameArrayListForClick.get(RecyclerViewItemPosition), Toast.LENGTH_LONG).show();
            }

            return false;
        }

        @Override
        public void onTouchEvent(RecyclerView Recyclerview, MotionEvent motionEvent) {

        }

        @Override
        public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

        }
    });

    return v;

}

public void JSON_HTTP_CALL(){

    RequestOfJSonArray = new JsonArrayRequest(HTTP_JSON_URL,

            new Response.Listener<JSONArray>() {
                @Override
                public void onResponse(JSONArray response) {

                    ParseJSonResponse(response);
                }
            },
            new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {

                }
            });

    requestQueue = Volley.newRequestQueue(getActivity());

    requestQueue.add(RequestOfJSonArray);
}

public void ParseJSonResponse(JSONArray array){

    for(int i = 0; i<array.length(); i++) {

        DataAdapter GetDataAdapter2 = new DataAdapter();

        JSONObject json = null;
        try {

            json = array.getJSONObject(i);

            GetDataAdapter2.setImageTitle(json.getString(Image_Name_JSON));

            // Adding image title name in array to display on RecyclerView click event.
            ImageTitleNameArrayListForClick.add(json.getString(Image_Name_JSON));

            GetDataAdapter2.setImageUrl(json.getString(Image_URL_JSON));

        } catch (JSONException e) {

            e.printStackTrace();
        }
        ListOfdataAdapter.add(GetDataAdapter2);
    }

    recyclerViewadapter = new RecyclerViewAdapter(ListOfdataAdapter, getActivity());

    recyclerView.setAdapter(recyclerViewadapter);
}
}

and error in logcat is :

                                                                          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2306)
                                                                          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2358)
                                                                          at android.app.ActivityThread.access$600(ActivityThread.java:156)
                                                                          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1340)
                                                                          at android.os.Handler.dispatchMessage(Handler.java:99)
                                                                          at android.os.Looper.loop(Looper.java:153)
                                                                          at android.app.ActivityThread.main(ActivityThread.java:5297)
                                                                          at java.lang.reflect.Method.invokeNative(Native Method)
                                                                          at java.lang.reflect.Method.invoke(Method.java:511)
                                                                          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833)
                                                                          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
                                                                          at dalvik.system.NativeStart.main(Native Method)
                                                                       Caused by: java.lang.NullPointerException
                                                                          at ir.dadevarzjooya.MainActivity2.HomeFragment2.onCreateView(HomeFragment2.java:60)
                                                                          at android.app.Fragment.performCreateView(Fragment.java:1695)
                                                                          at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:885)
                                                                          at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1057)
                                                                          at android.app.BackStackRecord.run(BackStackRecord.java:694)
                                                                          at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1435)
                                                                          at android.app.Activity.performStart(Activity.java:5131)
                                                                          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2279)
                                                                          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2358) 
                                                                          at android.app.ActivityThread.access$600(ActivityThread.java:156) 
                                                                          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1340) 
                                                                          at android.os.Handler.dispatchMessage(Handler.java:99) 
                                                                          at android.os.Looper.loop(Looper.java:153) 
                                                                          at android.app.ActivityThread.main(ActivityThread.java:5297) 
                                                                          at java.lang.reflect.Method.invokeNative(Native Method) 
                                                                          at java.lang.reflect.Method.invoke(Method.java:511) 
                                                                          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833) 
                                                                          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600) 
                                                                          at dalvik.system.NativeStart.main(Native Method) 

any body have idea ? i think this problem is caused from view ...

Answer 1

The problem is on this line.

recyclerView = getActivity().findViewById(R.id.recyclerview1);

Replace that line with this

recyclerView = v.findViewById(R.id.recyclerview1);

You should get your recycler view from the fragment's layout which is being initialized in the beginning of your method, not from the activity