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RecyclerView inside fragment is not clickable

I am programming a music player app and having a problem with a RecyclerView inside a fragment(which connects to tab layout in my main activity) from some reason the RecyclerView is not clickable and when I am pressing an item the app just close.
Can you please help me with that?
I added the fragment class and the adapter class.
public class MusicAdapter extends RecyclerView.Adapter<MusicAdapter.MusicviewHolder> {
private List<Music> songs;
public Resources res;
Context context;
public MusicAdapter(Context context, List<Music> songs) {
String s = String.valueOf(R.drawable.lionkingposter);
songs.add(new Music("jgggug", "Circle of life", "Alton John ", "Lion King",s));
// }
this.songs = songs;//constructor
this.context=context;
}
interface MusicListener {
void onMusicClicked(int position, View view);
// void onDeleteClicked(int position);
}
MusicListener listener;
public void setListener(MusicListener listener) {
this.listener = listener;
}
#Override
public MusicviewHolder onCreateViewHolder(ViewGroup parent, int viewType) {//function design the cell
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.cell, parent, false);
MusicviewHolder musicviewholder = new MusicviewHolder(view);
return musicviewholder;
}
#Override
public void onBindViewHolder(MusicviewHolder holder, int position) {//this function takes the object and put it in the cell
Music music = songs.get(position);
if (music.getPhoto() != null) {
try {
holder.songImg.setImageResource(Integer.parseInt(music.getPhoto()));
} catch (Exception e) {
//holder.songImg.setImageURI(Uri.parse(music.getPhoto()));
byte[] decodedString = Base64.decode(music.getPhoto(), Base64.DEFAULT);
Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
holder.songImg.setImageBitmap(decodedByte);
}
} else {
holder.songImg.setImageResource(0);
}
holder.songName.setText(music.getTitle());
holder.movieName.setText(music.getAlbum());
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Intent intent=new Intent(context,MediaPlayer.class);
//intent.putExtra("song",position);
//context.startActivity(intent);
Toast.makeText(context,"hello",Toast.LENGTH_SHORT);
}
});
}
#Override
public int getItemCount() {
return songs.size();
}
public class MusicviewHolder extends RecyclerView.ViewHolder {
TextView songName;
TextView movieName;
ImageView songImg;
public MusicviewHolder(#NonNull View itemView) {
super(itemView);
songName = itemView.findViewById(R.id.song_title);
movieName = itemView.findViewById(R.id.movie_title);
songImg = itemView.findViewById(R.id.song_img);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (listener != null)
listener.onMusicClicked(getAdapterPosition(), v);
}
}
);
}
}
}
public class SongFragment extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
private RecyclerView recyclerview;
private RecyclerView.Adapter myadapter;
private RecyclerView.LayoutManager layoutManager;
View view;
private ArrayList<Music> songs=new ArrayList<>();
private Resources res;
public Context context;
Bundle bundle;
// private ShowSongActivity show;
public SongFragment() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* #param param1 Parameter 1.
* #param param2 Parameter 2.
* #return A new instance of fragment SongsFragment.
*/
// TODO: Rename and change types and number of parameters
public static SongFragment newInstance(String param1, String param2) {
SongFragment fragment = new SongFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
ArrayList<Music> listTemp = MusicManager.getInstance(getContext()).getMusics();
if (listTemp != null)
songs.addAll((Collection<? extends Music>) listTemp.clone());
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_songs, container, false);
recyclerview = (RecyclerView) view.findViewById(R.id.songs_recycler);
MusicAdapter musicAdapter = new MusicAdapter(context,songs);
recyclerview.setLayoutManager(new LinearLayoutManager(getActivity()));
recyclerview.setAdapter(musicAdapter);
recyclerview.setLayoutManager(new LinearLayoutManager(getContext(), RecyclerView.VERTICAL, false));
return view;
}
}

Try to set onClickListener on the holder into the onBindViewHolder method and when invoke the listener it need to be passed into the setListener(MusicListener listener) method. Something like this:
holder.itemView.setOnClickListener(v -> this.listener.onMusicClicked(position, v);});
In my opinion, it's better to change the interface MusicListener like that:
interface MusicListener {
void onMusicClicked(int position, Music item);
}
And return the clicked item directly like this:
holder.itemView.setOnClickListener(v -> this.listener.onMusicClicked(position, songs.get(position);});
Furthermore, it is better to pass the MusicListener when you create the RecyclerView Adapter because you can easily forget to set it and this will cause the Nullpointer Exception.
I am not sure why you are doing this: String s = String.valueOf(R.drawable.lionkingposter); If you want to keep the Drawable resource in the class make property int (Integer) and keep only the R.drawable.lionkingposter when you set the drawable resource to an ImageView use setBackgroundResource method as described here
I hope this helped ;)

I faced the same problem, Don't know the actual cause of this but I found a working solution.
You need to create a Listener class which implements RecyclerView.OnItemTouchListener
public class MatchClickListener implements RecyclerView.OnItemTouchListener {
private GestureDetector gestureDetector;
private ClickListener clickListener;
public MatchClickListener(Context context, final RecyclerView recyclerView, final ClickListener clickListener) {
this.clickListener = clickListener;
gestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
#Override
public boolean onSingleTapUp(MotionEvent e) {
return true;
}
#Override
public void onLongPress(MotionEvent e) {
View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
if (child != null && clickListener != null) {
clickListener.onLongClick(child, recyclerView.getChildPosition(child));
}
}
});
}
#Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
View child = rv.findChildViewUnder(e.getX(), e.getY());
if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
clickListener.onClick(child, rv.getChildPosition(child));
}
return false;
}
#Override
public void onTouchEvent(#NotNull RecyclerView rv, MotionEvent e) {
}
#Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
}
public interface ClickListener {
void onClick(View view, int position);
void onLongClick(View view, int position);}
}
Then call it from your fragment or mainactivity where recyler view is created
recyclerView.addOnItemTouchListener(new MatchClickListener
(getActivity(),recyclerView, new MatchClickListener.ClickListener() {
#Override
public void onClick(View view, int position) {
Intent in =new Intent(getActivity(), TournamentPage.class);
startActivity(in);
}
#Override
public void onLongClick(View view, int position) {
}
}));

First, implement the interface in fragment something like that.
public class SongFragment extends Fragment implements MusicAdapter.MusicListener
Second, override the method.
#Override
public void onMusicClicked(int position, View view) {
}
Third, Pass the view to the method. but below the adapter object
musicAdapter.setListener(this::onItemClick);
Here is the complete solution.
public class SongFragment extends Fragment implements MusicAdapter.MusicListener {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
private RecyclerView recyclerview;
private RecyclerView.Adapter myadapter;
private RecyclerView.LayoutManager layoutManager;
View view;
private ArrayList<Music> songs=new ArrayList<>();
private Resources res;
public Context context;
Bundle bundle;
// private ShowSongActivity show;
public SongFragment() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* #param param1 Parameter 1.
* #param param2 Parameter 2.
* #return A new instance of fragment SongsFragment.
*/
// TODO: Rename and change types and number of parameters
public static SongFragment newInstance(String param1, String param2) {
SongFragment fragment = new SongFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
ArrayList<Music> listTemp = MusicManager.getInstance(getContext()).getMusics();
if (listTemp != null)
songs.addAll((Collection<? extends Music>) listTemp.clone());
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_songs, container, false);
recyclerview = (RecyclerView) view.findViewById(R.id.songs_recycler);
MusicAdapter musicAdapter = new MusicAdapter(context,songs);
recyclerview.setLayoutManager(new LinearLayoutManager(getActivity()));
recyclerview.setAdapter(musicAdapter);
recyclerview.setLayoutManager(new LinearLayoutManager(getContext(), RecyclerView.VERTICAL, false));
musicAdapter.setListener(this::onItemClick);
return view;
}
#Override
public void onMusicClicked(int position, View view) {
// here implement which you want
}
}

Update recyclerview data

since several days I try to handle data in recyclerview in viewpager2. The viewpager has an adapter managing the data in recyclerview. But everything I try to do seems to not work. Maybe I missundersteand the purpose or something. I hope you can help me.
This activity manages the viewpager and its adapter. It sends the data to the inner recyclerview:
public class AudioFilePanel extends AppCompatActivity
{
private String currentTab;
private ViewPagerAdapter adapter;
private ViewPager2 viewPager;
private TabLayout tabLayout;
private Map<String, List<String>> content;
private String path;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_audio_file_panel);
viewPager = findViewById(R.id.view_pager2);
tabLayout = findViewById(R.id.tabs);
Button addFilesByTag = findViewById(R.id.add_files_with_tag);
if (null == currentTab)
{
currentTab = "music";
}
content = listByTag();
adapter = new ViewPagerAdapter(getApplicationContext(), new ArrayList<>(content.values()));
viewPager.setAdapter(adapter);
new TabLayoutMediator(tabLayout, viewPager,
(tab, position) -> tab.setText(content.keySet().toArray()[position].toString())).attach();
tabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener()
{
#Override
public void onTabSelected(TabLayout.Tab tab)
{
currentTab = tab.getText().toString();
}
#Override
public void onTabUnselected(TabLayout.Tab tab)
{
}
#Override
public void onTabReselected(TabLayout.Tab tab)
{
}
});
addFilesByTag.setOnClickListener(l ->
{
Intent fileBrowser = new Intent(AudioFilePanel.this, FileBrowser.class);
startActivityForResult(fileBrowser, 1);
});
}
private void updateViweData()
{
content = listByTag();
adapter = new ViewPagerAdapter(getApplicationContext(), new ArrayList<>(content.values()));
viewPager.setAdapter(adapter);
}
private Map<String, List<String>> listByTag()
{
Map<String, List<String>> result = new HashMap<>();
DirectoryDao dao = new DirectoryDao(getApplicationContext());
String[] categories = {"music", "ambience", "effect"};
for (String category : categories)
{
List<String> directories =
dao.getDirectoriesForCategory(category).stream().map(Directory::getPath).collect(Collectors.toList());
result.put(category, directories);
}
return result;
}
This is the view pager adapter. It takes the data directly from the activity and should trigger data update in the inner recyclerview every time when an item will be clicked. See line 118-128:
public class ViewPagerAdapter extends RecyclerView.Adapter<ViewPagerAdapter.ViewHolder>
{
private List<List<String>> filesListsByCategory;
private LayoutInflater mInflater;
private Context ctx;
private ItemListAdapter adapter;
private List<String> categoryFiles;
public ViewPagerAdapter(Context context, List<List<String>> data)
{
this.mInflater = LayoutInflater.from(context);
this.filesListsByCategory = data;
this.ctx = context;
}
#NotNull
#Override
public ViewHolder onCreateViewHolder(#NotNull ViewGroup parent, int viewType)
{
return new ViewHolder(mInflater.inflate(R.layout.item_viewpager, parent, false));
}
#Override
public void onBindViewHolder(ViewHolder holder, int position)
{
FileBrowserService fbs = new FileBrowserService();
categoryFiles = filesListsByCategory.get(position);
adapter = new ItemListAdapter(categoryFiles, new ItemList.OnListFragmentInteractionListener()
{
#Override
public void onListFragmentInteraction(String item)
{
categoryFiles = fbs.getFiles(categoryFiles.get(position));
categoryFiles.add(0, "previous directory");
updateUi(adapter, holder);
}
});
holder.myView.setAdapter(adapter);
}
private void updateUi(ItemListAdapter adapter, ViewHolder holder)
{
adapter.notifyDataSetChanged();
holder.myView.setAdapter(adapter);
}
#Override
public int getItemCount()
{
return filesListsByCategory.size();
}
class ViewHolder extends RecyclerView.ViewHolder
{
RecyclerView myView;
RelativeLayout relativeLayout;
ViewHolder(View itemView)
{
super(itemView);
myView = itemView.findViewById(R.id.my_list);
myView.setLayoutManager(new LinearLayoutManager(ctx));
relativeLayout = itemView.findViewById(R.id.container);
}
}
}
It is the adapter of inner recyclerview. It represents just a list of elements:
public class ItemListAdapter extends RecyclerView.Adapter<ItemListAdapter.ViewHolder>
{
private List<String> files;
private final OnListFragmentInteractionListener mListener;
public ItemListAdapter(List<String> items, OnListFragmentInteractionListener listener)
{
files = items;
mListener = listener;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
return new ViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.fragment_item, parent, false));
}
#Override
public void onBindViewHolder(final ViewHolder holder, int position)
{
holder.file = files.get(position);
holder.mContentView.setText(files.get(position));
holder.mView.setOnClickListener(v ->
{
if (null != mListener)
{
// Notify the active callbacks interface (the activity, if the
// fragment is attached to one) that an item has been selected.
mListener.onListFragmentInteraction(holder.file);
}
});
}
#Override
public int getItemCount()
{
return files.size();
}
class ViewHolder extends RecyclerView.ViewHolder
{
private final View mView;
private final TextView mContentView;
private String file;
private ViewHolder(View view)
{
super(view);
mView = view;
mContentView = view.findViewById(R.id.content);
}
}
}
The last thing is the ItemList fragment.
public class ItemList extends Fragment
{
// TODO: Customize parameter argument names
private static final String ARG_COLUMN_COUNT = "column-count";
// TODO: Customize parameters
private int mColumnCount = 1;
private OnListFragmentInteractionListener mListener;
/**
* Mandatory empty constructor for the fragment manager to instantiate the fragment (e.g. upon screen orientation
* changes).
*/
public ItemList()
{
}
// TODO: Customize parameter initialization
#SuppressWarnings("unused")
public static ItemList newInstance(int columnCount)
{
ItemList fragment = new ItemList();
Bundle args = new Bundle();
args.putInt(ARG_COLUMN_COUNT, columnCount);
fragment.setArguments(args);
return fragment;
}
#Override
public void onAttach(Context context)
{
super.onAttach(context);
if (context instanceof OnListFragmentInteractionListener)
{
mListener = (OnListFragmentInteractionListener) context;
} else
{
throw new RuntimeException(context.toString() + " must implement OnListFragmentInteractionListener");
}
}
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
if (getArguments() != null)
{
mColumnCount = getArguments().getInt(ARG_COLUMN_COUNT);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_item_list, container, false);
if (view instanceof RecyclerView)
{
Context context = view.getContext();
RecyclerView recyclerView = (RecyclerView) view;
if (mColumnCount <= 1)
{
recyclerView.setLayoutManager(new LinearLayoutManager(context));
} else
{
recyclerView.setLayoutManager(new GridLayoutManager(context, mColumnCount));
}
recyclerView.setAdapter(new ItemListAdapter(getArguments().getStringArrayList("list"), mListener));
}
return view;
}
#Override
public void onDetach()
{
super.onDetach();
mListener = null;
}
/**
* This interface must be implemented by activities that contain this fragment to allow an interaction in this
* fragment to be communicated to the activity and potentially other fragments contained in that activity.
* <p/>
* See the Android Training lesson
* <a href= "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnListFragmentInteractionListener
{
// TODO: Update argument type and name
void onListFragmentInteraction(String item);
}
}
When I click, the data won't update. What I would like to have is:

This is what you have to do
add this method into your adapter class
public void updateData(List<String> filesList, int flag) {
if (flag == 0) { //append
for (int i = 0; i < filesList.size(); i++) {
files.add(messageList.get(i));
notifyItemInserted(getItemCount());
}
} else { //clear all
files.clear();
notifyDataSetChanged();
}
}
Then whenever you need to update recycle view call like below
mItemListAdapter.updateData(yourNewListOfItems, 0);
if you need to reset recycle-view call like below
mItemListAdapter.updateData(null, 1);

Add notifyDataSetChanged() in your adapter

Android Fragment with ViewPagers oncreateView Called in Wrong Fragment

I have a main activity which shows 3 fragments inside View Pagers with tabs.
mainActivity.java
public class mainActivity extends AppCompatActivity {
globalVariableActivity variable = new globalVariableActivity();
private APIService mAPIService;
private TextView mResponseTv;
private RecyclerView recyclerView;
private Token token = new Token("","","");
private Gson gson = new Gson();
private Context context=mainActivity.this;
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//check if token is still active
String current_token=token.getToken(context);
MyFirebaseInstanceIDService Fcm= new MyFirebaseInstanceIDService();
Fcm.onTokenRefresh(context,current_token);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(false);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new BeritaFragment(), "Berita");
adapter.addFragment(new DiskusiFragment(), "Diskusi");
adapter.addFragment(new PesanFragment(), "Pesan");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
//Toast.makeText(context,"Item " + position + " shown.", Toast.LENGTH_SHORT).show();
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
Toast.makeText(context,"Position : " + position + " Title : "+ mFragmentTitleList.get(position) + " shown.", Toast.LENGTH_SHORT).show();
return mFragmentTitleList.get(position);
}
}
interface LyfecycleListener {
void onCreatedView();
}
here's the first fragment code
beritaFragment.java
public class BeritaFragment extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private APIService mAPIService = APIUtils.getAPIService();;
private Gson gson = new Gson();
private TextView createdAtText;
private TextView judulText;
private ImageView imageView;
private RecyclerView mRecyclerView;
private ListAdapter mListadapter;
private ArrayList<DataBerita> list_berita= new ArrayList<>();
private OnFragmentInteractionListener mListener;
public BeritaFragment() {
}
// TODO: Rename and change types and number of parameters
public static BeritaFragment newInstance(String param1, String param2) {
BeritaFragment fragment = new BeritaFragment();
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getBeritaTask getBerita= new getBeritaTask();
try {
Log.d("berita :", "On create 1");
getBerita.execute().get(10000, TimeUnit.MILLISECONDS);
Log.d("berita :", "On create 2");
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
} catch (TimeoutException e) {
e.printStackTrace();
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_berita, container, false);
Log.d("Berita","On create view");
Toast.makeText(getActivity() ,"Berita Fragment onCreateView", Toast.LENGTH_SHORT).show();
ArrayList<DataBerita> data_berita;
mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_view);
judulText = (TextView)view.findViewById(R.id.summary_judul);
createdAtText = (TextView)view.findViewById(R.id.created_at);
//imageView = (ImageView)view.findViewById(R.id.gambar);
final LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
mRecyclerView.setLayoutManager(layoutManager);
//data_berita=getBeritaList();
Log.d("Berita","1");
Log.d("Berita List : ", list_berita.toString());
Log.d("Berita","3");
mListadapter = new ListAdapter(list_berita);
mRecyclerView.setAdapter(mListadapter);
//Log.d("Berita view :", view.toString());
return view;
}
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
public class ListAdapter extends RecyclerView.Adapter<ListAdapter.ViewHolder>
{
private ArrayList<DataBerita> dataList;
public ListAdapter(ArrayList<DataBerita> data)
{
this.dataList = data;
}
public class ViewHolder extends RecyclerView.ViewHolder
{
TextView judulText;
TextView waktuText;
ImageView gambarView;
public ViewHolder(View itemView)
{
super(itemView);
this.judulText = (TextView) itemView.findViewById(R.id.summary_judul);
this.waktuText = (TextView) itemView.findViewById(R.id.created_at);
//this.gambarView = (ImageView) itemView.findViewById(R.id.gambar);
}
}
#Override
public ListAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.berita_list_layout, parent, false);
ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
}
#Override
public void onBindViewHolder(ListAdapter.ViewHolder holder, final int position)
{
Uri ImageURI=Uri.parse(dataList.get(position).getGambar_utama());
holder.judulText.setText(dataList.get(position).getSummary_judul());
holder.waktuText.setText(dataList.get(position).getCreated_at());
//holder.gambarView.setImageURI(ImageURI);
holder.itemView.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
Toast.makeText(getActivity(), "Item " + position + " is clicked.", Toast.LENGTH_SHORT).show();
}
});
}
#Override
public int getItemCount()
{
return dataList.size();
}
}
private class getBeritaTask extends AsyncTask<Void, Void, Void> {
protected void onPreExecute() {
Log.d("Berita","2.1");
}
protected Void doInBackground(Void... voids) {
mAPIService.getBeritaList().enqueue(new Callback<Berita>() {
#Override
public void onResponse(Call<Berita> call, Response<Berita> response) {
list_berita = new ArrayList<>();
DataBerita data_berita = new DataBerita("","","","");
String id_berita;
String judul;
String gambar_utama;
String created_at;
Log.d("Berita","2.2");
if(response.isSuccessful()) {
Berita body = gson.fromJson(response.body().toString(),Berita.class);
for (int i = 0; i < body.getList_berita().getData().size(); i ++) {
id_berita=body.getList_berita().getData().get(i).getId_berita();
judul=body.getList_berita().getData().get(i).getSummary_judul();
gambar_utama=body.getList_berita().getData().get(i).getGambar_utama();
created_at=body.getList_berita().getData().get(i).getCreated_at();
data_berita = new DataBerita(id_berita,judul,gambar_utama,created_at);
list_berita.add(data_berita);
}
Log.d("Berita List",list_berita.toString());
}else{
Log.d("Berita", "Fail");
}
}
#Override
public void onFailure(Call<Berita> call, Throwable t) {
Log.d("Berita Fail", t.getMessage());
}
});
return null;
}
}
here's the 2nd and 3rd fragment (these 2 fragments are still mostly empty, with code for toast and log only for now)
DiskusiFragment.java
public class DiskusiFragment extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
private OnFragmentInteractionListener mListener;
public DiskusiFragment() {
// Required empty public constructor
}
// TODO: Rename and change types and number of parameters
public static DiskusiFragment newInstance(String param1, String param2) {
DiskusiFragment fragment = new DiskusiFragment();
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
Toast.makeText(getActivity() ,"Diskusi Fragment onCreateView", Toast.LENGTH_SHORT).show();
return inflater.inflate(R.layout.fragment_diskusi, container, false);
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
here's the problem,
fragment onCreateView function seems to be called on / in the wrong fragment.
when I start the app here's what happened :
Item position 0 , 1, and 2 is called
1st fragment on create view is called, and 2nd fragment on create view is called immediately
what happens next, depends on what I do :
when I change from 1st fragment => 2nd fragment, 3rd fragment on create view is called
when I change from 1st fragment => 3rd fragment, 3rd fragment on create view is called
when I switch from 2nd fragment => 1st fragment, no fragment on create view called
when I switch from 2nd fragment => 3rd fragment, no fragment on create view called
when I switch from 3rd fragment => 2nd fragment, no fragment on create view called (or sometimes 1st fragment on create view is called)
when I change from 3rd fragment => 1st fragment, 1st fragment on create view called
is this what suppose (in regard to onCreateView function is called on the wrong fragment) to happen?
if not, where did I code wrong?
Thank you very much
*EDIT : this behaviour is normal, I'm really new to android. Very sorry for the inconvenience guys

The FragmentPagerAdapter keeps additional fragments, besides the one shown, in the resumed state.
If you want to initialize stuff in the fragment you should do it when
OnCreate is called.
Anything that is related to the UI been loaded properly should happen on
onViewCreated
In addition, if you want to receive more information about how to handle fragments inside a ViewPager
#Shreyas Shetty answered it really well on this thread

What do you mean by "wrong" fragment? View pager creates next fragment prior to navigating to it to make the transition smooth and quick. And when the fragment is created its lifecycle methods are called accordingly, there's nothing wrong with this behaviour. If you want to perform some action when the user swipes to specific fragment in your view pager, you can use OnPageChangeListener.

Unable to get an onClick event in RecyclerView in a Fragment [duplicate]

This question already has answers here:
RecyclerView onClick
(49 answers)
Closed 4 years ago.
I'm using a Json to get data and images for my application. The images are displayed in a RecyclerView that is inside of a Fragment (Tab1.java) which is connected to MainActivity. I want to set it up in such a way, so that when the user clicks on an image in the RecyclerView, a new Activity (ViewImage.java) is launched and the image is displayed there.
So far, I've been able to fetch the Json data and display it in a recycler view. The images are displayed perfectly, but when I tried to setup "setItemOnClickListener", the application started to crash (I've marked that line with a comment in Tab1.java).
Tab1.java
/*
* A simple {#link Fragment} subclass.
* Activities that contain this fragment must implement the
* {#link Tab1.OnFragmentInteractionListener} interface
* to handle interaction events.
* Use the {#link Tab1#newInstance} factory method to
* create an instance of this fragment.
*/
public class Tab1 extends Fragment implements CardAdapter.OnItemClickListener{
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
public static final String EXTRA_URL = "imageUrl";
private RecyclerView mRecyclerView;
private CardAdapter mCardAdapter;
private ArrayList<Card> mCardList;
TextView textView;
private OnFragmentInteractionListener mListener;
public Tab1() {
// Required empty public constructor
}
/*
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* #param param1 Parameter 1.
* #param param2 Parameter 2.
* #return A new instance of fragment Tab1.
*/
// TODO: Rename and change types and number of parameters
public static Tab1 newInstance(String param1, String param2) {
Tab1 fragment = new Tab1();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
// #Override
public void onCreate(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_tab1, container, false);
mRecyclerView = v.findViewById(R.id.recycler_view);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
mCardList = new ArrayList<>();
/*
* Retrofit code to fetch the Json data
*/
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(ApiService.BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();
ApiService service = retrofit.create(ApiService.class);
Call<JsonResponse> call = service.getPopulationData();
final StringBuffer flagData = new StringBuffer();
call.enqueue(new Callback<JsonResponse>(){
#Override
public void onResponse(Call<JsonResponse> call, Response<JsonResponse> response) {
ArrayList<Worldpopulation> population=new ArrayList(response.body()
.getWorldpopulation());
for (Worldpopulation j : population) {
String countryName = j.getCountry();
String imageUrl = j.getFlag();
int rank = j.getRank();
mCardList.add(new Card(imageUrl, countryName, rank));
}
mCardAdapter = new CardAdapter(getActivity(), mCardList);
mRecyclerView.setAdapter(mCardAdapter);
// This particular line of code is causing the application to crash.
// And I cannot figure out how this is supposed to be implemented.
mCardAdapter.setItemOnClickListener((CardAdapter.OnItemClickListener) getContext());
}
#Override
public void onFailure(Call<JsonResponse> call, Throwable t) {
Log.d("JSONError", t.getMessage());
}
});
// Inflate the layout for this fragment
return v;
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
#Override
public void onItemClick(int position) {
Intent imagePreview = new Intent(getActivity(), ViewImage.class);
Card clickedItem = mCardList.get(position);
imagePreview.putExtra(EXTRA_URL, clickedItem.getImageUrl());
startActivity(imagePreview);
}
/*
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
CardAdapter.java
public class CardAdapter extends RecyclerView.Adapter<CardAdapter.CardViewHolder> {
private Context mContext;
private ArrayList<Card> mCardList;
private OnItemClickListener mListener;
public interface OnItemClickListener {
void onItemClick(int position);
}
public void setItemOnClickListener(OnItemClickListener listener) {
mListener = listener;
}
public CardAdapter(Context context, ArrayList<Card> cardList) {
mContext = context;
mCardList = cardList;
}
#Override
public CardViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(mContext).inflate(R.layout.card, parent, false);
return new CardViewHolder(v);
}
#Override
public void onBindViewHolder(CardViewHolder holder, int position) {
Card currentItem = mCardList.get(position);
String imageUrl = currentItem.getImageUrl();
String countryName = currentItem.getCountryName();
int rank = currentItem.getRank();
holder.mTextViewCountry.setText(countryName);
holder.mTextViewRank.setText("Rank: " + rank);
Picasso.get().load(imageUrl).fit().centerInside().into(holder.mImageView);
}
#Override
public int getItemCount() {
return mCardList.size();
}
public class CardViewHolder extends RecyclerView.ViewHolder {
public ImageView mImageView;
public TextView mTextViewCountry;
public TextView mTextViewRank;
public CardViewHolder(View itemView) {
super(itemView);
mImageView = itemView.findViewById(R.id.image_view);
mTextViewCountry = itemView.findViewById(R.id.text_view_country_name);
mTextViewRank = itemView.findViewById(R.id.text_view_rank);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (mListener != null) {
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION) {
mListener.onItemClick(position);
}
}
}
});
}
}
}
ViewImage.java
public class viewimage extends appcompatactivity {
#override
protected void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.activity_view_image);
// imageview where the image is to be displayed in this activity
imageview imageview = findviewbyid(r.id.fullscreenimage);
bundle bundle = getintent().getextras();
if (bundle != null) {
string imageurl = bundle.getstring("extra_url");
if (imageurl != null) {
picasso.get().load(imageurl).fit().centerinside().into(imageview);
}
}
}
}

as you already know this method is no longer available in the RecyclerView class.
My approach towards implementing onClick events in a RecyclerView is something like this:
class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
interface OnClickListener {
void onClick(Item item);
}
private final List<Item> dataset;
private final OnClickListener l;
public MyAdapter(List<Item> data, OnClickListener listener) {
this.dataset = data;
this.l = listener;
}
#Override MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = //inflate layout
MyClick click = new MyClick() {
onClick(int position) {
if (l != null) {
l.onClick(dataset.get(position));
}
}
};
return new MyViewHolder(click, v);
}
static class MyViewHolder {
final MyClick l;
public MyViewHolder(MyClick listener, View view) {
super(view);
l = listener;
// inflate views
view.setOnClickListener(new OnClickListener() {
if (l != null) {
l.onClick(getAdapterPosition());
}
});
}
interface MyClick {
void onClick(int position);
}
}
}
class MyActivity extends AppCompatActivity {
#Override void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// set layout
MyAdapter adapter = new MyAdapter(getData(), new OnClickListener() {
#Override onClick(Item item) {
// do stuff with item
}
});
}
}

ViewPager setCurrentItem(position) not working after orientation change

i'm facing an issue i can't seem to resolve and i'd like some help.
My app is composed by an activity containing a fragment. After the user taps on a suggestion, activity's method onSuggestionClicked(String cardId) is called and activity's content is replaced with a new PagerFragment_new.
#Override
public void onSuggestionClicked(String cardId) {
Log.d("activity","ID:\t" + cardId);
PagerFragment_new pagerFragment = PagerFragment_new.getInstance(
Injection.provideMtgDatabase(getApplicationContext()),
activityPresenter.getAllCardExpansionIds(cardId),
this);
ActivityUtils.replaceFragment(getSupportFragmentManager(), pagerFragment, R.id.MTGRecallActivity_container);
}
PagerFragment_new contains a ViewPager to display CardInfoFragment_new
public class PagerFragment_new extends MtgRecallFragment_new implements PagerFragmentContract.View {
private View fragmentView;
private ViewPager viewPager;
private PagerFragmentContract.Presenter presenter;
private ScreenSlidePageAdapter_new adapter;
private MtgDatabase database;
private String[] printingsIds;
private ScreenSlidePageAdapter_new.ActivePresenterListener listener;
public PagerFragment_new() {
//Required empty constructor
}
public static PagerFragment_new getInstance(MtgDatabase database, String[] printingsIds, ScreenSlidePageAdapter_new.ActivePresenterListener listener) {
PagerFragment_new instance = new PagerFragment_new();
instance.setDatabase(database);
instance.setPrintingsIds(printingsIds);
instance.listener = listener;
return instance;
}
//other stuff
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
setRetainInstance(true);
super.onCreate(savedInstanceState);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
setHasOptionsMenu(true);
fragmentView = inflater.inflate(R.layout.fragment_pager, container, false);
viewPager = (ViewPager) fragmentView.findViewById(R.id.PAGERFRAG_VIEWPAGER);
adapter = new ScreenSlidePageAdapter_new(getChildFragmentManager(), printingsIds, database, viewPager);
adapter.setListener(listener);
viewPager.setAdapter(adapter);
viewPager.setOffscreenPageLimit(1);
return fragmentView;
}
#Override
public void setPresenter(PagerFragmentContract.Presenter presenter) {
this.presenter = presenter;
}
}
The adapter to manage ViewPager's element's is ScreenSlidePageAdapter_new, it is responsible of instantiating CardInfoFragments.
public class ScreenSlidePageAdapter_new extends FragmentStatePagerAdapter {
private String[] printingsIds;
private String firstItemId;
private MtgDatabase database;
public ActivePresenterListener activity;
private ViewPager viewPager;
public ScreenSlidePageAdapter_new(FragmentManager fm, String[] printingsIds, MtgDatabase database, ViewPager viewPager) {
super(fm);
this.printingsIds =printingsIds;
this.database = database;
this.firstItemId = printingsIds[0];
this.viewPager = viewPager;
}
#Override
public Fragment getItem(int position) {
//todo create a bundle with cardId
Bundle bundle = new Bundle();
bundle.putString("CardID", printingsIds[position]);
bundle.putString("FirstItemId", firstItemId);
CardInfoFragment_new cardInfoFragment_new = CardInfoFragment_new.getInstance(viewPager);
cardInfoFragment_new.setArguments(bundle);
CardInfoPresenter cardInfoPresenter = new CardInfoPresenter(cardInfoFragment_new, database);
activity.setActivePresenter(cardInfoPresenter);
return cardInfoFragment_new;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
super.destroyItem(container, position, object);
}
public void setListener(ActivePresenterListener listener) {
this.activity = listener;
}
#Override
public int getCount() {
return printingsIds.length;
}
public interface ActivePresenterListener {
void setActivePresenter(BasePresenter presenter);
}}
Finally, here's the code of CardInfoFragment:
public class CardInfoFragment_new extends MtgRecallFragment_new
implements CardInfoContract.View,
CardPrintingsAdapter.OnItemClickListener {
private ViewPager viewPager;
public CardInfoContract.Presenter presenter;
private View fragmentView;
private MTGCard mtgCard;
RecyclerView printingsRecyclerView;
CardPrintingsAdapter cardPrintingsAdapter;
private String firstItemId; //the first id
public CardInfoFragment_new() {
//required empty constructor
}
private void setViewPager(ViewPager viewPager) {
this.viewPager = viewPager;
}
public static CardInfoFragment_new getInstance(ViewPager viewPager) {
CardInfoFragment_new cardInfoFragment_new = new CardInfoFragment_new();
cardInfoFragment_new.setViewPager(viewPager);
return cardInfoFragment_new;
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
setRetainInstance(true);
presenter.start();
String cardId = getArguments().getString("CardID");
firstItemId = getArguments().getString("FirstItemId");
mtgCard = presenter.getCardData(cardId);
super.onCreate(savedInstanceState);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
fragmentView = inflater.inflate(R.layout.fragment_card_info_new, container, false);
setUpCardInfoView(fragmentView);
return fragmentView;
}
public void setUpCardInfoView(final View view){
//others view set-up action omitted
cardprintingsContainer = (LinearLayout) view.findViewById(R.id.CARDINFO_printingsContainer);
printingsRecyclerView = (RecyclerView)fragmentView.findViewById(R.id.CARDINFO_printings_recyclerView);
final List<String> printings = presenter.getCardPrintings(firstItemId, mtgCard.getName());
if (printings.size() < 40) {
setupPrintings(printings,printingsRecyclerView);
}
else {
LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
LinearLayout printingsRow = new LinearLayout(getContext());
printingsRow = (LinearLayout)inflater.inflate(R.layout.card_info_printings_row,printingsRow,true);
printingsRow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
setupPrintings(printings, printingsRecyclerView);
}
});
ImageView printingssetImage = (ImageView)printingsRow.findViewById(R.id.CARDINFO_printingsRow_setImage);
printingssetImage.setVisibility(View.INVISIBLE);
TextView printingssetName = (TextView)printingsRow.findViewById(R.id.CARDINFO_printingsRow_setName);
printingssetName.setText("Click to see all the "+printings.size()+ " versions");
cardprintingsContainer.addView(printingsRow);
}
}
public void setupPrintings(List<String> printings, RecyclerView recyclerView) {
cardPrintingsAdapter =
new CardPrintingsAdapter(getContext(), printings);
cardPrintingsAdapter.setOnItemClickListener(this);
UnscrollableLayoutManager layoutManager = new UnscrollableLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false);
recyclerView.setAdapter(cardPrintingsAdapter);
recyclerView.setLayoutManager(layoutManager);
}
#Override
public void onItemClick(View itemView, int position) {
int i = viewPager.getAdapter().getCount();
viewPager.setCurrentItem(position);
}
#Override
public void onDestroy() {
presenter = null;
mtgCard = null;
super.onDestroy();
}}
When user click on a RecyclerView item, CardInfoFragment's method onItemClick(View itemView, int position) is called and the viewpager is set to current position. Everything as expected.
THE PROBLEM
When the orientation changes, fragments are able to retain their states, but viewPager.setCurrentItem(position) does nothing, and i'm not able to change displayed fragment.
I already checked:
ViewPager instance and adapters instances corresponds to those passed to Fragments
onItemClick is fired
this questions question1 question2
If i use
android:configChanges="orientation|screenSize"
in manifest it works even after config changes, but i don't want to use this option since is discouraged.
Thanks in advance!

By default, when certain key configuration changes happen on Android (a common example is an orientation change), Android fully restarts the running Activity to help it adjust to such changes.
When you define android:configChanges="keyboardHidden|orientation" in your AndroidManifest, you are telling Android: "Please don't do the default reset when the keyboard is pulled out, or the phone is rotated; I want to handle this myself. Yes, I know what I'm doing".
So use configChanges.
The use of this is discouraged, IF you don't know how to use it. But for a case like this, I would suggest you use it. IF not, still the activity will be recreated. which just takes time, resources, and I don't see why you would want that to happen.