Develop Reference

How to pass information from one adapter to other?

i have two adapters one for my card view and the other one for my drawer. The cards contains links to other options in the app and the drawer contains the same options. What i want is when user clicks on the card, the options in the drawer menu should get selected. Here is my code.
Drawer Adapter:
#SuppressWarnings({"rawtypes", "ConstantConditions"})
public class DrawerAdapter extends RecyclerView.Adapter<DrawerAdapter.ViewHolder> {
private List<DrawerItem> items;
private Map<Class<? extends DrawerItem>, Integer> viewTypes;
private SparseArray<DrawerItem> holderFactories;
private OnItemSelectedListener listener;
public DrawerAdapter(List<DrawerItem> items) {
this.items = items;
this.viewTypes = new HashMap<>();
this.holderFactories = new SparseArray<>();
processViewTypes();
}
#NonNull
#Override
public ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
ViewHolder holder = holderFactories.get(viewType).createViewHolder(parent);
holder.adapter = this;
return holder;
}
#Override
#SuppressWarnings("unchecked")
public void onBindViewHolder(#NonNull ViewHolder holder, int position) {
items.get(position).bindViewHolder(holder);
}
#Override
public int getItemCount() {
return items.size();
}
#Override
public int getItemViewType(int position) {
return viewTypes.get(items.get(position).getClass());
}
private void processViewTypes() {
int type = 0;
for (DrawerItem item : items) {
if (!viewTypes.containsKey(item.getClass())) {
viewTypes.put(item.getClass(), type);
holderFactories.put(type, item);
type++;
}
}
}
public void setSelected(int position) {
DrawerItem newChecked = items.get(position);
if (!newChecked.isSelectable()) {
return;
}
for (int i = 0; i < items.size(); i++) {
DrawerItem item = items.get(i);
if (item.isChecked()) {
item.setChecked(false);
notifyItemChanged(i);
break;
}
}
newChecked.setChecked(true);
notifyItemChanged(position);
if (listener != null) {
listener.onItemSelected(position);
}
}
public void setListener(OnItemSelectedListener listener) {
this.listener = listener;
}
static abstract class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private DrawerAdapter adapter;
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
}
#Override
public void onClick(View v) {
adapter.setSelected(getAdapterPosition());
}
}
public interface OnItemSelectedListener {
void onItemSelected(int position);
}
}
Card Adapter:
public class CardAdapter extends RecyclerView.Adapter<CardAdapter.ViewHolder> {
;
private RecyclerView parentRecycler;
private List<Card> data;
public CardAdapter(List<Card> data) {
this.data = data;
}
#Override
public void onAttachedToRecyclerView(#NonNull RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
parentRecycler = recyclerView;
}
#NonNull
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
View v = inflater.inflate(R.layout.item_card, parent, false);
return new ViewHolder(v);
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
Card card = data.get(position);
holder.getAdapterPosition();
Glide.with(holder.itemView.getContext())
.asGif()
.load(card.getCardIcon())
.into(holder.gifImageView);
holder.textView.setText(card.getCardName());
}
#Override
public int getItemCount() {
return data.size();
}
class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private GifImageView gifImageView;
private TextView textView;
public ViewHolder(View itemView) {
super(itemView);
gifImageView = itemView.findViewById(R.id.card_gif);
textView = itemView.findViewById(R.id.card_name);
itemView.findViewById(R.id.container).setOnClickListener(this);
}
public void showText() {
int parentHeight = ((View) gifImageView.getParent()).getHeight();
float scale = (parentHeight - textView.getHeight()) / (float) gifImageView.getHeight();
gifImageView.setPivotX(gifImageView.getWidth() * 0.5f);
gifImageView.setPivotY(0);
gifImageView.animate().scaleX(scale)
.withEndAction(new Runnable() {
#Override
public void run() {
textView.setVisibility(View.VISIBLE);
// gifImageView.setColorFilter(Color.BLACK);
}
})
.scaleY(scale).setDuration(200)
.start();
}
public void hideText() {
textView.setVisibility(View.INVISIBLE);
gifImageView.animate().scaleX(1f).scaleY(1f)
.setDuration(200)
.start();
}
#Override
public void onClick(View v) { parentRecycler.smoothScrollToPosition(getAdapterPosition());
}
}
}
}
P.S: I am new to programming any kind of help is appreciated.[As you can see in the image below that I have cards in the main view and the same options are in the drawer menu for example question papers. Now when the user clicks on question paper in the main view the question paper in drawer menu should get selected.[][1]][1]
thank you!
[1]: https://i.stack.imgur.com/FooVb.jpg

How to implement getItemViewType() for multiple layout in RecyclerView in a Movie Database app

I am creating a movie app using TMDB api, Retrofit, Gson and Glide. I have two recyclerView and two layout to inflate. But I am unable to inflate 2 layout in recyclerView adapter.
I have already implemented popular and upcoming movie list in 2 different recyclerView. But they are showing using 1 single layout. I want to inflate popular movies in one layout and upcoming movies in another layout. I can't set the condition for getItemViewType() method. How can I check for popular and upcoming movies list in getItemViewType() method and implement it on onCreateViewHolder() method of recyclerView.
MovieAdapter class:
public class MovieAdapter extends RecyclerView.Adapter<MovieAdapter.MovieViewHolder> {
private Context context;
private ArrayList<Movie> movieArrayList;
public MovieAdapter(Context context, ArrayList<Movie> movieArrayList) {
this.context = context;
this.movieArrayList = movieArrayList;
}
#NonNull
#Override
public MovieViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.movie_list_item, parent, false);
return new MovieViewHolder(view);
}
#Override
public int getItemViewType(int position) {
return super.getItemViewType(position);
}
#Override
// Set values to the list item components
public void onBindViewHolder(#NonNull MovieViewHolder holder, int position) {
holder.movieTitle.setText(movieArrayList.get(position).getOriginalTitle());
holder.rating.setText(String.valueOf(movieArrayList.get(position).getVoteAverage()));
String imagePath = "https://image.tmdb.org/t/p/w500" + movieArrayList.get(position).getPosterPath();
Glide.with(context)
.load(imagePath)
.placeholder(R.drawable.loading)
.into(holder.movieImage);
}
#Override
public int getItemCount() {
return movieArrayList == null ? 0 : movieArrayList.size();
}
public class MovieViewHolder extends RecyclerView.ViewHolder {
TextView movieTitle, rating;
ImageView movieImage;
public MovieViewHolder(#NonNull View itemView) {
super(itemView);
movieImage = itemView.findViewById(R.id.ivMovieImage);
movieTitle = itemView.findViewById(R.id.tvTitle);
rating = itemView.findViewById(R.id.tvRating);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION) {
Movie selectedMovie = movieArrayList.get(position);
Intent intent = new Intent(context, MovieActivity.class);
intent.putExtra("movie", selectedMovie);
context.startActivity(intent);
}
}
});
}
}
}
MainActivity class:
public class MainActivity extends AppCompatActivity {
private ArrayList<Movie> popularMovie, topRatedMovie;
private RecyclerView recyclerViewPopular, recyclerViewUpcoming;
private MovieAdapter movieAdapter, upcomingAdapter;
private SwipeRefreshLayout swipeRefreshLayout;
private static ViewPager mPager;
private static int currentPage = 0;
private static int NUM_PAGES = 0;
String[] urls = new String[] {
"https://image.tmdb.org/t/p/w500/udDclJoHjfjb8Ekgsd4FDteOkCU.jpg",
"https://image.tmdb.org/t/p/w500//2bXbqYdUdNVa8VIWXVfclP2ICtT.jpg",
"https://image.tmdb.org/t/p/w500//zfE0R94v1E8cuKAerbskfD3VfUt.jpg",
"https://image.tmdb.org/t/p/w500//lcq8dVxeeOqHvvgcte707K0KVx5.jpg",
"https://image.tmdb.org/t/p/w500//w9kR8qbmQ01HwnvK4alvnQ2ca0L.jpg"
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initSlider();
getPopularMovies();
getUpcomingMovies();
swipeRefreshLayout = findViewById(R.id.swipe_layout);
swipeRefreshLayout.setColorSchemeResources(R.color.colorPrimaryDark);
swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
getPopularMovies();
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
swipeRefreshLayout.setRefreshing(false);
}
}, 4000);
}
});
}
public void getPopularMovies() {
MovieDataService movieDataService = RetrofitInstance.getService();
Call<MovieDBResponse> callPopular = movieDataService.getPopularMovies(this.getString(R.string.apiKey));
callPopular.enqueue(new Callback<MovieDBResponse>() {
#Override
public void onResponse(Call<MovieDBResponse> call, Response<MovieDBResponse> response) {
MovieDBResponse movieDBResponse = response.body();
if(movieDBResponse!=null && movieDBResponse.getMovies()!=null) {
popularMovie = (ArrayList<Movie>) movieDBResponse.getMovies();
showOnRecyclerView();
}
}
#Override
public void onFailure(Call<MovieDBResponse> call, Throwable t) { }
});
}
public void getUpcomingMovies() {
MovieDataService movieDataService = RetrofitInstance.getService();
Call<MovieDBResponse> callUpcoming = movieDataService.getUpcomingMovies(this.getString(R.string.apiKey));
callUpcoming.enqueue(new Callback<MovieDBResponse>() {
#Override
public void onResponse(Call<MovieDBResponse> call, Response<MovieDBResponse> response) {
MovieDBResponse movieDBResponse = response.body();
if(movieDBResponse!=null && movieDBResponse.getMovies()!=null) {
topRatedMovie = (ArrayList<Movie>) movieDBResponse.getMovies();
showOnRecyclerView();
}
}
#Override
public void onFailure(Call<MovieDBResponse> call, Throwable t) { }
});
}
private void showOnRecyclerView() {
recyclerViewPopular = findViewById(R.id.rvMovies);
recyclerViewUpcoming = findViewById(R.id.rvTopMovies);
RecyclerView.LayoutManager popularLayoutManager = new LinearLayoutManager(this);
RecyclerView.LayoutManager upcomingLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
recyclerViewUpcoming.setLayoutManager(upcomingLayoutManager);
recyclerViewPopular.setLayoutManager(popularLayoutManager);
movieAdapter = new MovieAdapter(this, popularMovie);
upcomingAdapter = new MovieAdapter(this, topRatedMovie);
if (this.getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
recyclerViewPopular.setLayoutManager(new GridLayoutManager(this, 2));
}else {
recyclerViewPopular.setLayoutManager(new GridLayoutManager(this, 4));
}
recyclerViewPopular.setItemAnimator(new DefaultItemAnimator());
recyclerViewUpcoming.setItemAnimator(new DefaultItemAnimator());
recyclerViewPopular.setAdapter(movieAdapter);
recyclerViewUpcoming.setAdapter(upcomingAdapter);
movieAdapter.notifyDataSetChanged();
upcomingAdapter.notifyDataSetChanged();
}
}
I want to inflate 2 different layout "movie_list_item.xml" and "upcoming_movie_list_item.xml" in onCreateViewHolder() method.

With in your adapter class(MovieAdapter) create a new constructor and add extra params of Int or enum whatever simple for you i am just giving you simple example:-
public class MovieAdapter extends RecyclerView.Adapter<MovieAdapter.MovieViewHolder> {
private Context context;
private ArrayList<Movie> movieArrayList;
private int viewType;
public MovieAdapter(Context context, ArrayList < Movie > movieArrayList, int viewType) {
this.context = context;
this.movieArrayList = movieArrayList;
this.viewType=viewType;
}
#NonNull
#Override
public MovieViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view;
if (viewType == 1) {
//Popular movie layout
view = LayoutInflater.from(parent.getContext()).inflate(R.layout.movie_list_item, parent, false);
} else {
//upcoming movie layout
view = LayoutInflater.from(parent.getContext()).inflate(R.layout.movie_list_item, parent, false);
}
return new MovieViewHolder(view);
}
#Override
public int getItemViewType(int position) {
if (viewType == 1)
return 1; //Popular Movie Layout
else
return 2; //Upcoming Movie Layout
// return super.getItemViewType(position);
}
#Override
// Set values to the list item components
public void onBindViewHolder(#NonNull MovieViewHolder holder, int position) {
holder.movieTitle.setText(movieArrayList.get(position).getOriginalTitle());
holder.rating.setText(String.valueOf(movieArrayList.get(position).getVoteAverage()));
String imagePath = "https://image.tmdb.org/t/p/w500" + movieArrayList.get(position).getPosterPath();
Glide.with(context)
.load(imagePath)
.placeholder(R.drawable.loading)
.into(holder.movieImage);
}
#Override
public int getItemCount() {
return movieArrayList == null ? 0 : movieArrayList.size();
}
public class MovieViewHolder extends RecyclerView.ViewHolder {
TextView movieTitle, rating;
ImageView movieImage;
public MovieViewHolder(#NonNull View itemView) {
super(itemView);
movieImage = itemView.findViewById(R.id.ivMovieImage);
movieTitle = itemView.findViewById(R.id.tvTitle);
rating = itemView.findViewById(R.id.tvRating);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION) {
Movie selectedMovie = movieArrayList.get(position);
Intent intent = new Intent(context, MovieActivity.class);
intent.putExtra("movie", selectedMovie);
context.startActivity(intent);
}
}
});
}
}
and within your activity change on this method only
private void showOnRecyclerView() {
recyclerViewPopular = findViewById(R.id.rvMovies);
recyclerViewUpcoming = findViewById(R.id.rvTopMovies);
RecyclerView.LayoutManager popularLayoutManager = new LinearLayoutManager(this);
RecyclerView.LayoutManager upcomingLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
recyclerViewUpcoming.setLayoutManager(upcomingLayoutManager);
recyclerViewPopular.setLayoutManager(popularLayoutManager);
movieAdapter = new MovieAdapter(this, popularMovie,1);
upcomingAdapter = new MovieAdapter(this, topRatedMovie,2);
if (this.getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
recyclerViewPopular.setLayoutManager(new GridLayoutManager(this, 2));
} else {
recyclerViewPopular.setLayoutManager(new GridLayoutManager(this, 4));
}
recyclerViewPopular.setItemAnimator(new DefaultItemAnimator());
recyclerViewUpcoming.setItemAnimator(new DefaultItemAnimator());
recyclerViewPopular.setAdapter(movieAdapter);
recyclerViewUpcoming.setAdapter(upcomingAdapter);
movieAdapter.notifyDataSetChanged();
upcomingAdapter.notifyDataSetChanged();
}

Create layout for movie_empty_item
public class MovieAdapter extends RecyclerView.Adapter<MovieAdapter.MovieViewHolder> {
private Context context;
private ArrayList<Movie> movieArrayList;
//add this two line
private static final int EMPTY_VIEW_TYPE = 0;
private static final int NORMAL_VIEW_TYPE = 1;
public MovieAdapter(Context context, ArrayList<Movie> movieArrayList) {
this.context = context;
this.movieArrayList = movieArrayList;
}
#NonNull
#Override
public MovieViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
//return viewholder replace like this
if(viewType == NORMAL_VIEW_TYPE) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.movie_list_item, parent, false);
return new MovieViewHolder(view);
}else {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.movie_empty_item, parent, false);
return new EmptyViewHolder(view);
};
}
//getItemViewType return replace like this
#Override
public int getItemViewType(int position) {
return movieArrayList.size()>0?NORMAL_VIEW_TYPE:EMPTY_VIEW_TYPE;
}
#Override
// Set values to the list item components
public void onBindViewHolder(#NonNull MovieViewHolder holder, int position) {
holder.movieTitle.setText(movieArrayList.get(position).getOriginalTitle());
holder.rating.setText(String.valueOf(movieArrayList.get(position).getVoteAverage()));
String imagePath = "https://image.tmdb.org/t/p/w500" + movieArrayList.get(position).getPosterPath();
Glide.with(context)
.load(imagePath)
.placeholder(R.drawable.loading)
.into(holder.movieImage);
}
#Override
public int getItemCount() {
return movieArrayList.size() ? movieArrayList.size():1 ;
}
public class MovieViewHolder extends RecyclerView.ViewHolder {
TextView movieTitle, rating;
ImageView movieImage;
public MovieViewHolder(#NonNull View itemView) {
super(itemView);
movieImage = itemView.findViewById(R.id.ivMovieImage);
movieTitle = itemView.findViewById(R.id.tvTitle);
rating = itemView.findViewById(R.id.tvRating);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION) {
Movie selectedMovie = movieArrayList.get(position);
Intent intent = new Intent(context, MovieActivity.class);
intent.putExtra("movie", selectedMovie);
context.startActivity(intent);
}
}
});
}
}
public class EmptyViewHolder extends RecyclerView.ViewHolder {
public EmptyViewHolder(#NonNull View itemView) {
super(itemView);
}
}
}

Multi selection in RecyclerView?

Hello I am trying to implement multi select in recycler view android for showing an icon when clicked on that particular view, I have tried the below code and is working fine for that particular position, however there are other several views that too are getting updated, so please check and let me know what am I missing
Here is my adapter code:
public class ContactsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
Context context;
ArrayList<String> alContactName, alContactEmail, alContactNumber;
ArrayList<Boolean> alFromLinkedIn;
int mergeFlag=0;
private static SparseBooleanArray selectedItems;
ArrayList<Integer> alSelectedPositions;
public ContactsAdapter(Context context, ArrayList<String> alContactName, ArrayList<String> alContactEmail, ArrayList<String> alContactNumber, ArrayList<Boolean> alisFromLinkedIn) {
//Include one more variable for checking type i.e linked in or normal contact
super();
this.context = context;
this.alContactName = alContactName;
this.alContactEmail = alContactEmail;
this.alContactNumber = alContactNumber;
this.alFromLinkedIn = alisFromLinkedIn;
alSelectedPositions=new ArrayList<>();
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(context);
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_merge_contact, parent, false);
return new ContactsHolder(view);
}
#Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
try {
((ContactsHolder) holder).relMain.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
alSelectedPositions.add(position);
notifyDataSetChanged();
}
});
if(alSelectedPositions.get(position)==position){
((ContactsHolder) holder).imgMerge.setVisibility(View.VISIBLE);
}
else {
((ContactsHolder) holder).imgMerge.setVisibility(View.GONE);
}
} catch (Exception e) {
e.printStackTrace();
}
}

check updated code. I have modified the #tahsinRupam code.
#Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
try {
((ContactsHolder) holder).relMain.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if(alSelectedPositions.size>0)
{
for(int i=0;i<a1SelectedPositions.size;i++)
{
//if you want to cleasr previous details of array
if(a1SelectedPositions.contains(position))
alSelectedPositions.remove(position);
else
alSelectedPositions.add(position);
}
}
else
{
alSelectedPositions.add(position);
notifyDataSetChanged();
}
});
//update the position on scroll
for(int i=0;i<a1SelectedPositions.size;i++)
{
if(alSelectedPositions.get(i)==position){
((ContactsHolder)holder).imgMerge.setVisibility(View.VISIBLE);
}
else {
((ContactsHolder) holder).imgMerge.setVisibility(View.GONE);
}
}
} catch (Exception e) {
e.printStackTrace();
}
}

Recently I had to implement a multi select RecyclerView, below I attached a simplified code snippet for a clean way to implement multi-select feature in RecyclerView:
public class ItemAdapter extends RecyclerView.Adapter<ItemAdapter.ItemHolder> implements IMultiSelectableList<Item> {
boolean selectionMode = false;
HashSet<Item> selectedItems;
ArrayList<Item> mItems;
public ItemAdapter(ArrayList<Item> Items) {
super();
selectedItems = new HashSet<>();
mItems = Items;
}
public void enterSelectionModeWithItem(int selectedItemPosition){
if(selectedItemPosition >= 0 && selectedItemPosition < mItems.size())
selectedItems.add(mItems.get(selectedItemPosition));
selectionMode = true;
notifyDataSetChanged();
}
public void clearSelectionMode() {
selectionMode = false;
selectedItems.clear();
notifyDataSetChanged();
}
public class ItemHolder extends RecyclerView.ViewHolder{
ImageView mImage;
public ItemHolder(View itemView) {
super(itemView);
mImage = itemView.findViewById(R.id.image);
itemView.setOnLongClickListener(new View.OnLongClickListener() {
#Override
public boolean onLongClick(View view) {
if(!selectionMode){
int selectedPosition = getAdapterPosition();
Item selectedItem = mItems.get(selectedPosition);
enterSelectionModeWithItem(selectedItem);
return true;
}
return false;
}
});
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
int selectedPosition = getAdapterPosition();
Item selectedItem = mItems.get(selectedPosition);
//Capture Clicks in Selection Mode
if(selectionMode){
if(selectedItems.contains(selectedItem)){
selectedItems.remove(selectedItem);
mImage.setImageResource(R.drawable.ic_checkbox_blank_circle_outline_grey600_48dp);
} else {
selectedItems.add(selectedItem);
mImage.setImageResource(R.drawable.ic_checkbox_marked_circle_grey600_48dp);
}
}
}
});
}
public void setupView(Item item){
if(selectionMode){
if(selectedItems.contains(item)){
mImage.setImageResource(R.drawable.ic_checkbox_marked_circle_grey600_48dp);
} else {
mImage.setImageResource(R.drawable.ic_checkbox_blank_circle_outline_grey600_48dp);
}
}
}
#Override
public ItemAdapter.ItemHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.cell_item, parent, false);
return new ItemHolder(view);
}
#Override
public void onBindViewHolder(ItemAdapter.ItemHolder holder, int position) {
holder.setupView(mItems.get(position));
}
#Override
public int getItemCount() {
return mItems != null ? mItems.size() : 0;
}
}
, I use an image to show selection like Gmail app but feel free to use whatever works for you (background color, font style, etc).
P.S: I designed a callback interface for a simple selection interactions, if it helps I can attach it too! Cheers!

You've to do some specific things:
Initialize an int type array (type can be different) and assign 0 value to all it's elements.
int[] selectedPos = null;
public ContactsAdapter(Context context, ArrayList<String> alContactName, ArrayList<String> alContactEmail, ArrayList<String> alContactNumber, ArrayList<Boolean> alisFromLinkedIn) {
//Include one more variable for checking type i.e linked in or normal contact
super();
this.context = context;
this.alContactName = alContactName;
this.alContactEmail = alContactEmail;
this.alContactNumber = alContactNumber;
this.alFromLinkedIn = alisFromLinkedIn;
alSelectedPositions=new ArrayList<>();
for(int i = 0 ; i < alContactName.size() ; i++)
selectedPos[i] = 0;
}
Store the selected positions in selectedPos.
Then, check if the position is selected and set visibility accordingly:
In onBindViewHolder() add the following code:
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
try {
((ContactsHolder) holder).relMain.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
selectedPos[position] = 1;
notifyDataSetChanged();
}
});
} catch (Exception e) {
e.printStackTrace();
}
// Checking if the position was selected
if(selectedPos[position] == 1)
((ContactsHolder) holder).imgMerge.setVisibility(View.VISIBLE);
else
((ContactsHolder) holder).imgMerge.setVisibility(View.GONE);
}

I have resolved my issue here is the code if it could help someone:
#Override
public ContactsHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_merge_contact, parent, false);
final ContactsHolder holder = new ContactsHolder(view);
view.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (holder.getAdapterPosition() != RecyclerView.NO_POSITION) {
mSelectedItemPosition = holder.getAdapterPosition();
//notifyItemChanged(holder.getAdapterPosition());
notifyDataSetChanged();
}
}
});
return holder;
}
#Override
public void onBindViewHolder(ContactsHolder holder, int position) {
try {
if (mSelectedItemPosition == position) {
if (mergeFlag != 1) {
holder.imgMerge.setVisibility(View.VISIBLE);
mergeFlag = 1;
selectdParentId = contactsModels.get(position).alContactIdList;
} else{
//holder.relDone.setVisibility(View.GONE);
if (!selectdParentId.equals(contactsModels.get(position).alContactIdList)) {
holder.relDone.setVisibility(View.VISIBLE);
alChildId.add(contactsModels.get(position).alContactIdList);
} else {
holder.imgMerge.setVisibility(View.VISIBLE);
}
}
} else {
holder.imgMerge.setVisibility(View.GONE);
holder.relDone.setVisibility(View.GONE);
}
}

Items of Child RecyclerView of parent RecyclerView click event

I have a recycler view that displays a list of items.
Within each item, there is a title and another RecyclerView that display a list of items.
I want to access the click events of the items of the child RecyclerView.
Screenshot of the layout:
The parent RecyclerView:
public class DetailsGroupAdapter extends RecyclerView.Adapter<DetailsGroupAdapter.ViewHolder>{
private static OnItemClickListener listener;
private Context context;
private int lastPosition = -1;
RecyclerView mRecyclerView;
public interface OnItemClickListener {
void onItemClick(View itemView, int position);
void onGroupItemLongClick(View itemView, int groupPosition, int itemPosition);
void onGroupItemClick(View itemView, int groupPosition, int itemPosition);
}
public void setOnItemClickListener(OnItemClickListener listener) {
DetailsGroupAdapter.listener = listener;
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public TextView tvTitle;
public CardView cvContainer;
public RecyclerView rvItems;
public ViewHolder(final View itemView)
{
super(itemView);
tvTitle = itemView.findViewById(R.id.group_title);
cvContainer = itemView.findViewById(R.id.container);
rvItems = itemView.findViewById(R.id.rv_group_items);
//click listener setup
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Triggers click upwards to the adapter on click
if (listener != null)
listener.onItemClick(itemView, getLayoutPosition());
}
});
}
public void clearAnimation()
{
cvContainer.clearAnimation();
}
}
private List<DetailsGroup> itemList;
public DetailsGroupAdapter(List<DetailsGroup> itemList)
{
this.itemList = itemList;
}
#Override
public DetailsGroupAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
context = parent.getContext();
LayoutInflater inflater = LayoutInflater.from(context);
View layoutView = inflater.inflate(R.layout.item_details_group, parent, false);
mRecyclerView = (RecyclerView) parent;
return new ViewHolder(layoutView);
}
#Override
public void onBindViewHolder(final DetailsGroupAdapter.ViewHolder viewHolder, int groupPosition){
final DetailsGroup detailsGroup = itemList.get(groupPosition);
if(detailsGroup.Title != null){
viewHolder.tvTitle.setText(detailsGroup.Title);
} else {
viewHolder.tvTitle.setVisibility(View.GONE);
}
final DetailsGroupItemsAdapter detailsGroupAdapter = new DetailsGroupItemsAdapter(detailsGroup.itemsList, groupPosition);
detailsGroupAdapter.setOnItemClickListener(new DetailsGroupItemsAdapter.OnItemClickListener() {
#Override
public void onItemClick(View itemView, int position) {
if (listener != null){
listener.onGroupItemClick(itemView, (int) itemView.getTag(), position);
}
}
#Override
public void onLongClick(View itemView, int position) {
if (listener != null){
listener.onGroupItemLongClick(itemView, (int) itemView.getTag(), position);
}
}
});
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(context) {};
viewHolder.rvItems.setLayoutManager(linearLayoutManager);
viewHolder.rvItems.setAdapter(detailsGroupAdapter);
}
private void setAnimation(View viewToAnimate, int position)
{
if (position > lastPosition) {
AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
anim.setDuration(1000);
viewToAnimate.startAnimation(anim);
lastPosition = position;
}
}
#Override
public void onViewDetachedFromWindow(final ViewHolder holder)
{
((ViewHolder)holder).cvContainer.clearAnimation();
}
#Override
public long getItemId(int position) {
return itemList.get(position).hashCode();
}
#Override
public int getItemCount()
{
return itemList.size();
}
public void clear() {
itemList.clear();
notifyDataSetChanged();
}
public void addAll(List<DetailsGroup> list){
itemList.addAll(list);
notifyDataSetChanged();
}
}
The child RecyclerView:
public class DetailsGroupItemsAdapter extends RecyclerView.Adapter<DetailsGroupItemsAdapter.ViewHolder>{
private static OnItemClickListener listener;
private Context context;
private int lastPosition = -1;
private int groupPosition;
public interface OnItemClickListener {
void onItemClick(View itemView, int position);
void onLongClick(View itemView,int position);
}
public void setOnItemClickListener(OnItemClickListener listener) {
DetailsGroupItemsAdapter.listener = listener;
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public TextView tvTitle;
public TextView tvSubTitle;
public ImageView ivThumbnail;
public LinearLayout llContainer;
public ViewHolder(final View itemView)
{
super(itemView);
ivThumbnail = itemView.findViewById(R.id.thumbnail);
tvTitle = itemView.findViewById(R.id.title);
tvSubTitle = itemView.findViewById(R.id.subtitle);
llContainer = itemView.findViewById(R.id.container);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (listener != null)
listener.onItemClick(itemView, getLayoutPosition());
}
});
itemView.setOnLongClickListener(new View.OnLongClickListener() {
#Override
public boolean onLongClick(View view) {
if (listener != null)
listener.onLongClick(itemView, getLayoutPosition());
return false;
}
});
}
public void clearAnimation()
{
llContainer.clearAnimation();
}
}
private List<ItemDetail> itemList;
public DetailsGroupItemsAdapter(List<ItemDetail> itemList, int groupPosition)
{
this.itemList = itemList;
this.groupPosition = groupPosition;
}
#Override
public DetailsGroupItemsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
context = parent.getContext();
LayoutInflater inflater = LayoutInflater.from(context);
View layoutView = inflater.inflate(R.layout.item_details, parent, false);
return new ViewHolder(layoutView);
}
#Override
public void onBindViewHolder(DetailsGroupItemsAdapter.ViewHolder viewHolder, int position){
viewHolder.itemView.setTag(groupPosition);
ItemDetail itemDetail = itemList.get(position);
if(itemDetail.Title != null){
viewHolder.tvTitle.setText(itemDetail.Title);
} else {
viewHolder.tvTitle.setVisibility(View.GONE);
}
if(itemDetail.Sub_Title != null){
viewHolder.tvSubTitle.setText(itemDetail.Sub_Title);
} else {
viewHolder.tvSubTitle.setVisibility(View.GONE);
}
if(itemDetail.Thumbnail_Enabled){
PicManipulationUtility.SetGenericPictureFromThumbnailType(viewHolder.ivThumbnail, itemDetail.Thumbnail_Type, itemDetail.Thumbnail);
} else {
viewHolder.ivThumbnail.setVisibility(View.GONE);
}
setAnimation(viewHolder.llContainer, position);
}
private void setAnimation(View viewToAnimate, int position)
{
if (position > lastPosition) {
AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
anim.setDuration(1000);
viewToAnimate.startAnimation(anim);
lastPosition = position;
}
}
#Override
public void onViewDetachedFromWindow(final ViewHolder holder)
{
((ViewHolder)holder).llContainer.clearAnimation();
}
#Override
public long getItemId(int position) {
return itemList.get(position).hashCode();
}
#Override
public int getItemCount()
{
return itemList.size();
}
public void clear() {
itemList.clear();
notifyDataSetChanged();
}
public void addAll(List<ItemDetail> list){
itemList.addAll(list);
notifyDataSetChanged();
}
}
The classes used:
ItemDetail and DetailsGroup are POJOs to convert JSON into objects.
What I managed to do so far to temporarily fix the problem is:
In onBindViewHolder of parent RecyclerView, I grabbed the group position.
Then I passed the group position of the parent down to the child
adapter initializer in (DetailsGroupItemsAdapter)
Finally, in the child onBindViewHolder I set the tag to be the parent
group position(viewHolder.itemView.setTag(groupPosition);)
So in the click event of the child, I can say:
listener.onGroupItemClick(itemView, (int) itemView.getTag(), position);
Thus having both the group position and the child position in the bubbled event in my Activity or Fragment.
But I know for sure that the passed group position can change for any reason such as updating group items or removing items.
I want to know if there is a more robust solution to implement the click events of nested items in this case.

I used this https://gist.github.com/riyazMuhammad/1c7b1f9fa3065aa5a46f, especially
CustomItemClickListener.java :
public interface CustomItemClickListener {
public void onItemClick(View v, int position);
}
(Parent) RecyclerView modifications :
public class ItemsListAdapter extends RecyclerView.Adapter<ItemsListAdapter.ViewHolder> {
ArrayList<ItemListSingleItem> data;
Context mContext;
CustomItemClickListener listener;
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View mView = LayoutInflater.from(parent.getContext()).inflate(R.layout.items_list_single_item, parent, false);
final ViewHolder mViewHolder = new ViewHolder(mView);
mView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
listener.onItemClick(v, mViewHolder.getPosition());
}
});
return mViewHolder;
}
//[... the other "classical" parts of your code...]
}
Alone, it allowed me to have separate click events on child and parent
With some modifications, it led me to something similar to your "fix", I think, but maybe it'll give you some clues : I am giving the parent position and the parent listener to the child when constructing it, and then a click on the child produces the same behavior as a click on the parent
Child RecyclerView constructor :
public AppsAdapter(ArrayList<PackageInformation.InfoObject> dataSet, CustomOnItemClickListener customItemClickListener, int parentPos) {
appsDataSet = dataSet;
onItemClickListener = customItemClickListener;
parentPosition = parentPos;
}
Child RecyclerView onCreateViewHolder :
#Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
// Create a new view.
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.item_app, viewGroup, false);
// Create the ViewHolder to return
final AppsAdapter.ViewHolder mViewHolder = new AppsAdapter.ViewHolder(v);
// Add the Listener
v.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) { onItemClickListener.onItemClick(v, parentPosition); }
});
return mViewHolder;

Android: invert RecyclerView positions

I'm setting a RecyclerView behaving like a list, I want a button in the bottom of the list that when clicked adds more views, I'm thinking the easier way to do it is to make the position 0 as the first one in the bottom, and increasing the position to the top, so I can add views when the the view in position 0 is clicked.
If there is a better aproach for this problem do share.
Here is my adapter:
public class AddEventsAdapter extends RecyclerView.Adapter<AddEventsAdapter.ViewHolder> {
public List<String> items = new ArrayList<>();
public void addItem(String name) {
notifyItemInserted(items.size() - 1);
items.add(name);
}
public void removeItem(int position) {
items.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, items.size());
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
View view = inflater.inflate(R.layout.add_event_item, parent, false);
return new ViewHolder(view);
}
#Override
public int getItemCount() {
return items.size();
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
holder.setData(position);
holder.eventName.setText(i + "");
if(position == 0)
{
holder.theLayout.setBackgroundColor(Color.parseColor("#7F9099"));
holder.eventName.setText("Add");
}
}
static int i;
class ViewHolder extends RecyclerView.ViewHolder{
public TextView eventName;
public RelativeLayout theLayout;
public ViewHolder(final View itemView) {
super(itemView);
eventName = (TextView)itemView.findViewById(R.id.eventName);
theLayout = (RelativeLayout)itemView.findViewById(R.id.backgroundevent);
theLayout.setId(++i);
}
public void setData(final int position) {
theLayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (position == items.size() - 1) {
addItem("");
} else {
removeItem(position);
}
}
});
}
}
}
You may notice some errors in that, I've been over it for the last 10 hours and I'm having a logic breakdown

It's solved by addind this line to the LayoutManager .setReverseLayout(true);

you can add a footer view at the end of the list and inside that you can add your button. This is the link to create a footer in recycler view https://github.com/u3breeze/android-RecyclerView-WithHeaderAndFooter. You can add the views in the normal way