Develop Reference

I can't scroll the recyclerView of one fragment

I have 6 fragments in a Sliding tab layout. All of them have RecyclerView implemented in them. I have populated the RecyclerView. But I one of the fragments does not allow me to scroll, but the rest are working fine.
See the gif below:
This is my problem
Genres.java
public class Genres extends Fragment {
private static final String TAG = "Genres";
RecyclerView recyclerView_genre;
GenresAdapter genresAdapter;
ArrayList<GenresModel> Genrelist = new ArrayList<>();
long genreId;
String genreName;
Cursor genrecursor;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.genres_activity, container, false);
recyclerView_genre = view.findViewById(R.id.recyclerView_genre);
recyclerView_genre.setHasFixedSize(true);
LinearLayoutManager genreLayout = new LinearLayoutManager(getContext());
recyclerView_genre.setLayoutManager(genreLayout);
String[] proj1 = {MediaStore.Audio.Genres.NAME, MediaStore.Audio.Genres._ID};
genrecursor=getActivity().getContentResolver().query(MediaStore.Audio.Genres.EXTERNAL_CONTENT_URI,proj1,null, null, null);
if (genrecursor != null) {
if (genrecursor.moveToFirst()) {
do {
genreId = genrecursor.getLong(genrecursor.getColumnIndexOrThrow(MediaStore.Audio.Genres._ID));
genreName = genrecursor.getString(genrecursor.getColumnIndexOrThrow(MediaStore.Audio.Genres.NAME));
GenresModel genresModel = new GenresModel(genreId,genreName );
Genrelist.add(genresModel);
Collections.sort(Genrelist, new Comparator<GenresModel>() {
#Override
public int compare(GenresModel lhs, GenresModel rhs) {
return lhs.getGenreName().compareTo(rhs.getGenreName());
}
});
} while (genrecursor.moveToNext());
}
}
genrecursor.close();
genresAdapter = new GenresAdapter(getContext(),Genrelist);
recyclerView_genre.setAdapter(genresAdapter);
genresAdapter.notifyDataSetChanged();
return view;
}
GenresAdapter.java
public class GenresAdapter extends RecyclerView.Adapter<GenresAdapter.GenresHolder> {
Context gContext;
ArrayList<GenresModel> GenreList = new ArrayList<>();
public GenresAdapter(Context gContext, ArrayList<GenresModel> genreList) {
this.gContext = gContext;
GenreList = genreList;
}
#Override
public GenresAdapter.GenresHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view3 = LayoutInflater.from(gContext).inflate(R.layout.row_genre, parent, false);
return new GenresHolder(view3);
}
#Override
public void onBindViewHolder(GenresAdapter.GenresHolder holder, int position) {
final GenresModel genresModel1 = GenreList.get(position);
holder.genreText.setText( genresModel1.getGenreName());
}
#Override
public int getItemCount() {
return GenreList.size();
}
public class GenresHolder extends RecyclerView.ViewHolder {
TextView genreText;
public GenresHolder(View itemView) {
super(itemView);
genreText = itemView.findViewById(R.id.genreText);
}
}
}
activity_genre.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView_genre"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingTop="130dp"
>
</android.support.v7.widget.RecyclerView>
</LinearLayout>
row_genre.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginStart="10dp"
android:paddingTop="35dp"
>
<TextView
android:id="#+id/genreText"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="#ffffff"
android:textSize="14sp"
/>
</LinearLayout>

I found out the solution myself. Actually the the problem was with the viewpager transformation. I applied https://github.com/geftimov/android-viewpager-transformers/wiki/CubeOutTransformer to my viewpager and for some reason my first 3 fragments were working and rest were not!

How to show recycler view in the fragments of tablayout?

This is the data file which I have prepared in order to put data in the recycler view of my fragment
public class Data
{
public static ArrayList<Information> getData(){
ArrayList<Information> data= new ArrayList<>();
int [] images={
R.drawable.fuel,
R.drawable.milage,
R.drawable.serviceicon,
R.drawable.engine,
R.drawable.carbattery
};
String[] InformationAbout = {"245 Est miles to empty","4768 Miles Drove", "2 service compaings","245 EST mile to empty","72% battery level is good"};
for (int i=0;i<=images.length-1;i++)
{
Information current= new Information();
current.title=InformationAbout[i];
current.imageId=images[i];
data.add(current);
}
return data;
}
}
This is the information class which I have created in order to assign ID.
public class Information
{
public int imageId; //Reference to all the images in the drawable folder
public String title;
}
The listadapter which I have created in order to serve the recycler view and bind it to the view:
public class ListAdapter extends RecyclerView.Adapter<ListAdapter.MyViewHolder> {
private Activity context;
ArrayList<Information> data;
//LayoutInflater inflator;
public ListAdapter(Activity context , ArrayList<Information> data){
this.context = context;
this.data=data;
//this.inflator = LayoutInflater.from(context);
}
#Override
public ListAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = context.getLayoutInflater() ;
View view=inflater.inflate(R.layout.list_single,parent,false);
MyViewHolder myViewHolder= new MyViewHolder(view);
return myViewHolder;
}
#Override
public void onBindViewHolder(ListAdapter.MyViewHolder holder, int position) {
holder.textview.setText(data.get(position).title);
holder.imageView.setImageResource(data.get(position).imageId);
}
#Override
public int getItemCount() {
return data.size();
}
public class MyViewHolder extends RecyclerView.ViewHolder{
TextView textview;
ImageView imageView;
public MyViewHolder(View itemView) {
super(itemView);
textview = (TextView) itemView.findViewById(R.id.text_corresponding_image);
imageView = (ImageView) itemView.findViewById(R.id.icon_health_report);
}
}
}
This is the XML file which I am trying to serve in the adapter of the recyclerview.
list_single.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/list_single"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="#+id/icon_health_report"
android:layout_width="#dimen/tabel_image_width"
android:layout_height="#dimen/table_image_height"/>
<TextView
android:id="#+id/text_corresponding_image"
android:layout_width="wrap_content"
android:layout_height="20dp"/>
</LinearLayout>
This is the layout of the fragment:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.a129346.applicationpoc.Fragments.HealthReportFragmentTab">
<android.support.v7.widget.RecyclerView
android:id="#+id/vechile_report_lv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
This is the fragmenttab.java class where I am initiating the recycler view of the layout:
public class HealthReportFragmentTab extends Fragment {
private static String TAG = HealthReportFragmentTab.class.getSimpleName();
private RecyclerView recyclerView;
private ListAdapter mylistAdapter;
private HealthHistoryFragmentTab.OnFragmentInteractionListener mListener;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootview = inflater.inflate(R.layout.health_report_fragment, container, false);
initViews(rootview);
return rootview;
}
private void initViews(View view){
recyclerView = (RecyclerView) view.findViewById(R.id.vechile_report_lv);
mylistAdapter = new ListAdapter(getActivity(), Data.getData());
recyclerView.setAdapter(mylistAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
}
}
but I am not able to get the data on the this vehicle health tab. I want the images in the image array and text in front of the image which is the categories string array.

In the fragmentTab.java class, simply add:
public class HealthReportFragmentTab extends Fragment {
private static String TAG = HealthReportFragmentTab.class.getSimpleName();
private RecyclerView recyclerView;
private ListAdapter mylistAdapter;
private HealthHistoryFragmentTab.OnFragmentInteractionListener mListener;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootview = inflater.inflate(R.layout.health_report_fragment, container, false);
initViews(rootview);
return rootview;
}
private void initViews(View view){
recyclerView = (RecyclerView) view.findViewById(R.id.vechile_report_lv);
mylistAdapter = new ListAdapter(getActivity(), Data.getData());
recyclerView.setAdapter(mylistAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
}
}
In place of getActivity I applied getContext() method because it a fragment and then it needs a context in order to setlayout.

My views are giving me a null pointer exception

In my app,I get some data from my server. They are displayed fine,but when I pass them in my Detailed Fragment,then all views are null:(.
So here is my code.
public class MainActivityFragment extends Fragment {
public static final String TAG = "AelApp";
public static ArrayList<MyModel> listItemsList;
RecyclerView myList;
public static MatchReportsAdapter adapter;
public MainActivityFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
updateMatchReport();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
getActivity().setTitle("Match Report");
View rootView = inflater.inflate(R.layout.fragment_main_activity, container, false);
listItemsList = new ArrayList<>();
myList = (RecyclerView)rootView.findViewById(R.id.listview_match_reports);
final LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity());
myList.setHasFixedSize(true);
myList.setLayoutManager(linearLayoutManager);
adapter = new MatchReportsAdapter(getActivity(), listItemsList);
myList.setAdapter(adapter);
return rootView;
}
public void updateMatchReport(){
Intent i = new Intent(getActivity(), MatchReport.class);
getActivity().startService(i);
}
}
Adapter
public class MatchReportsAdapter extends
RecyclerView.Adapter<MatchReportsAdapter.RowHolder>{
private List<MyModel> reportsList;
private Context mContext;
private ImageLoader mImageLoader;
private int focused = 0;
public MatchReportsAdapter(Activity activity, List<MyModel> reportsLists){
this.reportsList = reportsLists;
this.mContext=activity;
}
#Override
public RowHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_items,null);
final RowHolder holder = new RowHolder(v);
return holder;
}
#Override
public void onBindViewHolder(RowHolder holder, int position) {
final MyModel listItems = reportsList.get(position);
holder.itemView.setSelected(focused==position);
holder.getLayoutPosition();
mImageLoader = AppController.getInstance().getImageLoader();
holder.thumbnail.setImageUrl(listItems.getImage(),mImageLoader);
holder.thumbnail.setDefaultImageResId(R.drawable.reddit_placeholder);
holder.name.setText(Html.fromHtml(listItems.getTitle()));
holder.relativeLayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String article = listItems.getArticle();
String image = listItems.getImage();
Intent i = new Intent(mContext, DetailedActivity.class);
i.putExtra("articleKey",article);
i.putExtra("imageKey",image);
mContext.startActivity(i);
}
});
}
#Override
public int getItemCount() {
return reportsList.size();
}
public class RowHolder extends RecyclerView.ViewHolder{
protected NetworkImageView thumbnail;
protected TextView name;
protected RelativeLayout relativeLayout;
public RowHolder(View itemView) {
super(itemView);
this.relativeLayout = (RelativeLayout)
itemView.findViewById(R.id.recLayout);
this.thumbnail =
(NetworkImageView)itemView.findViewById(R.id.thumbnail);
this.name = (TextView)itemView.findViewById(R.id.title);
}
}
}
DetailedActivity
public class DetailedActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detailed);
if(savedInstanceState == null){
getSupportFragmentManager()
.beginTransaction()
.add(R.id.detailed_match_reports,new DetailedActivityFragment())
.commit();
}
}
}
DetailedActivityFragment
public class DetailedActivityFragment extends Fragment {
TextView articleTextView;
String image;
String article;
ImageView imageView;
public DetailedActivityFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.fragment_detailed_activity, container, false);
articleTextView = (TextView)getActivity().findViewById(R.id.articleTextView);
imageView = (ImageView)getActivity().findViewById(R.id.imageNews);
Intent i = getActivity().getIntent();
article = i.getStringExtra("articleKey");
image = i.getStringExtra("imageKey");
Picasso.with(getActivity()).load(image).into(imageView);
articleTextView.setText(article);
return v;
}
}
All of my data are passed after clicking a row good. I know this as I debug the following lines.
article = i.getStringExtra("articleKey");
image = i.getStringExtra("imageKey");
and see that both String variables are not null. However,the both views(TextView,ImageView) of my detailed fragment are null.
Maybe I am doing something wrong with my xml file,and I don't see it.
activity_main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/match_reports"
tools:context="theo.testing.androidservices.fragments.MainActivityFragment">
</FrameLayout>
fragment_main_activity
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/recLayout"
tools:context=".activities.MainActivity"
android:background="#fff">
<android.support.v7.widget.RecyclerView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/listview_match_reports"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
/>
</RelativeLayout>
activity_detailed.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/detailed_match_reports"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="theo.testing.androidservices.activities.DetailedActivity"
tools:ignore="MergeRootFrame">
</FrameLayout>
and finally
fragment_detailed_activity
<?xml version="1.0" encoding="utf-8"?>
<ScrollView android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/imageNews"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
xmlns:android="http://schemas.android.com/apk/res/android">
<TextView
android:layout_gravity="center_horizontal"
android:padding="10dp"
android:text="xcvxcvxcv"
android:textColor="#000"
android:layout_marginTop="5dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/articleTextView"/>
</ScrollView>
What am I missing?
Thanks
Theo.

Change these
articleTextView = (TextView)getActivity().findViewById(R.id.articleTextView);
imageView = (ImageView)getActivity().findViewById(R.id.imageNews);
to
articleTextView = (TextView)v.findViewById(R.id.articleTextView);
imageView = (ImageView)v.findViewById(R.id.imageNews);
You'r passing data to DetailActivity. So first retrieve in DetailActivity and then pass to DetailFragment.
Also you need to pass data to DetailFragment using Bundle with setArguments(bundle)

Your Textview articleTextView is in the fragment but you are finding it in the activitys xml:
articleTextView = (TextView)getActivity().findViewById(R.id.articleTextView);
insetad you should do:
articleTextView = (TextView)(v.findViewById(R.id.articleTextView));
Do the same for Imageviewl.

ReclyclerView and CardView, onclick method perform the action on several CardViews at same time

I've got a RecyclerView which populates from an ArrayList. The output is a CardView layout.
In the Cardview, there are 2 buttons amongst other Views.
They only have to read the current value of a TextView, which by default is 1, and increase or decrease it.
The Arraylist contains 8 items.
When I run the app the UI works fine. Trouble is when I try to modify the value of the TextView.
The value is correctly increased and decreased on the CardView I'm working on, but ALSO the value is modified on another CardView. And in that second CardView, modifying its TextView value, also modifies the first one.
So, what am I doing wrong?
This is my Fragment:
public class Fragment_rosas extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.layout_rosas,container,false);
RecyclerView recyclerview_rosas;
RecyclerView.Adapter adaptador_rv_rosas;
RecyclerView.LayoutManager lm_rosas;
List rosas = new ArrayList();
rosas.add(new Tropa(1,R.drawable.minibarbaro, getResources().getString(R.string.barbaro),7,1));
recyclerview_rosas = (RecyclerView) view.findViewById(R.id.recyclerView_tropasRosas);
recyclerview_rosas.setHasFixedSize(true);
lm_rosas = new LinearLayoutManager(getContext());
recyclerview_rosas.setLayoutManager(lm_rosas);
adaptador_rv_rosas = new AdaptadorTropa(rosas);
recyclerview_rosas.setAdapter(adaptador_rv_rosas);
return view;
}
}
And here the part of code on my Adapter:
#Override
public void onBindViewHolder(final TropaViewHolder viewHolder, int i) {
viewHolder.imagen.setImageResource(items.get(i).getImagen());
viewHolder.nombre.setText(items.get(i).getNombre());
viewHolder.maxnivel.setText(String.valueOf(items.get(i).getNivelMax()));
viewHolder.espacioencamp.setText((String.valueOf(items.get(i).getEspacioEnCamp())));
final String nombre = items.get(i).getNombre();
final int maxnivel = items.get(i).getNivelMax();
viewHolder.nivelmas.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String niveltemp = viewHolder.nivel.getText().toString();
String nivelmaxtemp = viewHolder.maxnivel.getText().toString();
int nivel = Integer.parseInt(niveltemp);
int maxxnivel = Integer.parseInt(nivelmaxtemp);
int nuevonivel = nivel+1 ;
if (nuevonivel<=maxxnivel) {
viewHolder.txtv_nivel.setText(String.valueOf(nuevonivel));
}
}
});
My OnCreateViewHolder (nothing really happens here):
#Override
public TropaViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View v = LayoutInflater.from(viewGroup.getContext())
.inflate(R.layout.cardview, viewGroup, false);
return new TropaViewHolder(v);
}

Here is the solution, as mentioned in the comment above, it addresses two problems:
1. positiontoValueMap - saves current value for each position
2. onclicklistener is passed to the ViewHolder in onCreateViewHolder
Adapter Class
public class MyAdapter extends RecyclerView.Adapter {
private Context context;
private List<String> dataList;
private Map<Integer, Integer> positionToValueMap = new HashMap<>();
public MyAdapter(Context context, List<String> dataList) {
this.context = context;
this.dataList = dataList;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.recycler_view_item, null, false);
return new MyViewHolder(view, new OnRecyclerItemClickListener());
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
((MyViewHolder) holder).onRecyclerItemClickListener.updatePosition(position);
((MyViewHolder) holder).position.setText("" + position);
((MyViewHolder) holder).title.setText(dataList.get(position));
int valueToDisplay = 1;
if(positionToValueMap.containsKey(position)) {
valueToDisplay = positionToValueMap.get(position);
} else {
positionToValueMap.put(position, valueToDisplay);
}
((MyViewHolder) holder).valueView.setText("value: " + valueToDisplay);
}
#Override
public int getItemCount() {
return dataList.size();
}
private class MyViewHolder extends RecyclerView.ViewHolder {
private OnRecyclerItemClickListener onRecyclerItemClickListener;
private TextView position;
private TextView title;
private TextView valueView;
public MyViewHolder(View itemView, OnRecyclerItemClickListener onRecyclerItemClickListener) {
super(itemView);
itemView.setOnClickListener(onRecyclerItemClickListener);
this.onRecyclerItemClickListener = onRecyclerItemClickListener;
this.position = (TextView) itemView.findViewById(R.id.position);
this.title = (TextView) itemView.findViewById(R.id.title);
this.valueView = (TextView) itemView.findViewById(R.id.value_view);
}
}
private class OnRecyclerItemClickListener implements View.OnClickListener {
private int position = -1;
public void updatePosition(int position) {
this.position = position;
}
#Override
public void onClick(View v) {
int oldValue = positionToValueMap.get(position); // get current value
oldValue++; // increment
positionToValueMap.put(position, oldValue); // save current value
notifyItemChanged(position); // update clicked view so that it picks up the new saved value from the positionToValueMap in onBindViewHolder
}
}
}
RecyclerView item layout
<TextView
android:id="#+id/position"
android:layout_width="30dp"
android:layout_height="50dp"
android:textColor="#android:color/white"
android:gravity="center"
android:background="#android:color/holo_green_light"
android:layout_alignParentLeft="true"/>
<TextView
android:id="#+id/title"
android:layout_width="50dp"
android:layout_height="50dp"
android:textColor="#android:color/white"
android:gravity="center"
android:background="#android:color/holo_green_dark"
android:layout_toRightOf="#id/position" />
<TextView
android:id="#+id/value_view"
android:layout_width="match_parent"
android:layout_height="50dp"
android:textColor="#android:color/white"
android:gravity="center"
android:background="#android:color/holo_green_light"
android:layout_toRightOf="#id/title"
android:layout_alignParentRight="true"/>
</RelativeLayout>
And Activity to test it out
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
recyclerView.setAdapter(new MyAdapter(getApplicationContext(), getSampleData()));
}
private static List<String> getSampleData() {
List<String> dataList = new ArrayList<>();
dataList.add("zero");
dataList.add("one");
dataList.add("two");
dataList.add("three");
dataList.add("four");
dataList.add("five");
dataList.add("six");
dataList.add("seven");
dataList.add("eight");
dataList.add("nine");
dataList.add("ten");
dataList.add("eleven");
dataList.add("twelve");
dataList.add("thirteen");
dataList.add("fourteen");
dataList.add("fifteen");
dataList.add("sixteen");
dataList.add("seventeen");
dataList.add("eighteen");
dataList.add("nineteen");
dataList.add("twenty");
return dataList;
}
}
activity layout
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/root_view"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/white"/>
</RelativeLayout>

Android View Pager and RecycleView

I just want to display a list using recycle view inside the view pager. (ex. just like android home page icons)
But here list is not showing and without view pager it works.
Please can anyone tell me where is the problem...
Thank you..
activity.xml
<android.support.v4.view.ViewPager
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
obj_tile.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="5dp">
<ImageView
android:id="#+id/iv_icon"
android:layout_width="50dp"
android:layout_height="50dp"
android:src="#android:drawable/alert_light_frame" />
<TextView
android:id="#+id/tv_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:maxLines="2"
android:text="Group Title" />
</LinearLayout>
-fragment_screen_slide_page.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/my_recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="PageViewer Title" />
</RelativeLayout>
MainActivity.java
public class MainActivity extends FragmentActivity {
private static final int NUM_PAGES = 5;
private ViewPager mPager;
private PagerAdapter mPagerAdapter;
List<TilePojo> tilePojoList=new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Instantiate a ViewPager and a PagerAdapter.
mPager = (ViewPager) findViewById(R.id.pager);
mPagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager());
mPager.setAdapter(mPagerAdapter);
/*Context context=MainActivity.this;
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.fragment_screen_slide_page, null);
RecyclerView rvTiles = (RecyclerView) findViewById(R.id.my_recycler_view);
for (int i = 0; i < 10; i++) {
TilePojo tilePojo = new TilePojo(R.drawable.apple, "Button Title " + i);
tilePojoList.add(tilePojo);
}
TileAdapter adapter = new TileAdapter(tilePojoList);
if(adapter!=null) {
rvTiles.setAdapter(adapter);
rvTiles.setLayoutManager(new GridLayoutManager(this, 2));
}
*/
}
#Override
public void onBackPressed() {
if (mPager.getCurrentItem() == 0) {
// If the user is currently looking at the first step, allow the system to handle the
// Back button. This calls finish() on this activity and pops the back stack.
super.onBackPressed();
} else {
// Otherwise, select the previous step.
mPager.setCurrentItem(mPager.getCurrentItem() - 1);
}
}
/**
* A simple pager adapter that represents 5 ScreenSlidePageFragment objects, in
* sequence.
*/
private class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter {
public ScreenSlidePagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
return new ScreenSlidePageFragment();
}
#Override
public int getCount() {
return NUM_PAGES;
}
}
}
-ScreenSlidePageFragment.java
public class ScreenSlidePageFragment extends Fragment {
List<TilePojo> tilePojoList=new ArrayList<>();
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
ViewGroup rootView = (ViewGroup) inflater.inflate(
R.layout.fragment_screen_slide_page, container, false);
View v = inflater.inflate(R.layout.fragment_screen_slide_page, null);
RecyclerView rvTiles = (RecyclerView) v.findViewById(R.id.my_recycler_view);
for (int i = 0; i < 10; i++) {
TilePojo tilePojo = new TilePojo(R.drawable.apple, "Button Title " + i);
tilePojoList.add(tilePojo);
}
TileAdapter adapter = new TileAdapter(tilePojoList);
if(adapter!=null) {
rvTiles.setAdapter(adapter);
rvTiles.setLayoutManager(new GridLayoutManager(this.getActivity(), 2));
}
return rootView;
}
}
TileAdapter.java
public class TileAdapter extends RecyclerView.Adapter<TileAdapter.ViewHolder> {
private List<TilePojo> list;
public TileAdapter(List<TilePojo> list) {
this.list = list;
}
#Override
public TileAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
Context context = parent.getContext();
LayoutInflater inflater = LayoutInflater.from(context);
// Inflate the custom layout
View tileView = inflater.inflate(R.layout.obj_tile, parent, false);
// Return a new holder instance
ViewHolder viewHolder = new ViewHolder(tileView);
return viewHolder;
}
#Override
public void onBindViewHolder(TileAdapter.ViewHolder holder, int position) {
TilePojo tilePojo=list.get(position);
holder.imageView.setImageResource(tilePojo.getSrc());
holder.nameTextView.setText(tilePojo.getTitle());
}
#Override
public int getItemCount() {
return list.size();
}
public static class ViewHolder extends RecyclerView.ViewHolder {
// Your holder should contain a member variable
// for any view that will be set as you render a row
public TextView nameTextView;
public ImageView imageView;
// We also create a constructor that accepts the entire item row
// and does the view lookups to find each subview
public ViewHolder(View itemView) {
// Stores the itemView in a public final member variable that can be used
// to access the context from any ViewHolder instance.
super(itemView);
nameTextView = (TextView) itemView.findViewById(R.id.tv_title);
imageView = (ImageView) itemView.findViewById(R.id.iv_icon);
}
}
}

I got the answer..
I just replace the following (#ScreenSlidePageFragment.java)
rootView.findViewById(R.id.my_recycler_view);
Thank you.