Develop Reference

how displaying server information in Recyclerview?

I want to write a program to retrieve information from the server and display it in the Recycler View,But I have two problems.
When I add data to the table it will be added to the Recycler View list But when I delete, the list doesn't change.
2.Photos of each section cannot be loaded.
home.java
public class Home extends Fragment {
public Home() {
// Required empty public constructor
}
SwipeRefreshLayout srl;
RecyclerView rv;
FloatingActionButton add;
ArrayList<Post> al;
PostAdapter pa;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_home, container, false);
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
srl = getActivity().findViewById(R.id.srl);
rv = getActivity().findViewById(R.id.rv);
// add = getActivity().findViewById(R.id.add);
AndroidNetworking.initialize(getContext());
al = new ArrayList<>();
pa = new PostAdapter(getContext(),al);
rv.setHasFixedSize(true);
rv.setItemAnimator(new DefaultItemAnimator());
rv.setLayoutManager(new LinearLayoutManager(getContext()));
rv.setAdapter(pa);
update();
srl.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
update();
}
});
}
private void update(){
String id = al.size() == 0 ? "0" : al.get(0).getId();
AndroidNetworking.post(Urls.host+Urls.post)
.addBodyParameter("id",id)
.build()
.getAsObjectList(Post.class, new ParsedRequestListener<List<Post>>() {
#Override
public void onResponse(List<Post> response) {
srl.setRefreshing(false);
for (Post p : response){
al.add(0,p);
pa.notifyDataSetChanged();
}
}
#Override
public void onError(ANError anError) {
srl.setRefreshing(false);
}
});
}
}
postadapter.java
public class PostAdapter extends RecyclerView.Adapter<PostAdapter.ViewHolder> {
Context context;
ArrayList<Post> al;
LayoutInflater inflater;
public PostAdapter(Context ctx,ArrayList<Post> arl){
context = ctx;
al = arl;
inflater = LayoutInflater.from(context);
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = inflater.inflate(R.layout.rv_item,null,false);
RecyclerView.LayoutParams lp = new RecyclerView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);
view.setLayoutParams(lp);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
final Post s = al.get(position);
holder.title.setText(s.getTitle());
holder.text.setText(s.getText());
holder.date.setText(s.getDate());
holder.image.setImageUrl(Urls.host+s.getImage());
holder.image.setDefaultImageResId(R.drawable.material);
holder.image.setErrorImageResId(R.drawable.material);
}
#Override
public int getItemCount() {
return al.size();
}
class ViewHolder extends RecyclerView.ViewHolder{
ANImageView image;
AppCompatTextView title, text, date;
AppCompatImageView share;
public ViewHolder(View itemView) {
super(itemView);
image = itemView.findViewById(R.id.image);
title = itemView.findViewById(R.id.title);
text = itemView.findViewById(R.id.text);
date = itemView.findViewById(R.id.date);
}
}
}
post.java
public class Post {
String title,text, date,id;
int imageUrl;
public Post(int imageUrl, String title, String text, String time, String id) {
this.imageUrl = imageUrl;
this.title = title;
this.text = text;
this.date = time;
this.id = id;
}
public int getImage() {
return imageUrl;
}
public void setImage(int imageUrl) {
this.imageUrl = imageUrl;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
}

Try this
public class PostAdapter extends RecyclerView.Adapter<PostAdapter.ViewHolder> {
Context context;
ArrayList<Post> al;
ArrayList<Post> newDataList;
LayoutInflater inflater;
public PostAdapter(Context ctx,ArrayList<Post> arl){
context = ctx;
al = arl;
inflater = LayoutInflater.from(context);
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = inflater.inflate(R.layout.rv_item,null,false);
RecyclerView.LayoutParams lp = new RecyclerView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);
view.setLayoutParams(lp);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
final Post s = al.get(position);
holder.title.setText(s.getTitle());
holder.text.setText(s.getText());
holder.date.setText(s.getDate());
holder.image.setImageUrl(Urls.host+s.getImage());
holder.image.setDefaultImageResId(R.drawable.material);
holder.image.setErrorImageResId(R.drawable.material);
}
#Override
public int getItemCount() {
return al.size();
}
class ViewHolder extends RecyclerView.ViewHolder{
ANImageView image;
AppCompatTextView title, text, date;
AppCompatImageView share;
public ViewHolder(View itemView) {
super(itemView);
image = itemView.findViewById(R.id.image);
title = itemView.findViewById(R.id.title);
text = itemView.findViewById(R.id.text);
date = itemView.findViewById(R.id.date);
}
public ArrayList<Post> getDataSet() {
return al;
}
public void refresh(ArrayList<Post> list) {
newDataList = new ArrayList<>();
newDataList.addAll(list);
al.clear();
al.addAll(newDataList);
notifyDataSetChanged();
}
}
Now at time when you wants to add or delete try getting adapter.getDataSet()
and update list with adapter.refresh(yourList)

How to get onclick item in an android recyclerview and send its attributes to a new activity?

I'm developing an android app for online order. User needs to click on an food item in recyclerView and I'm trying to send the food ID to the AddOrderActivity. How can I get the FId and pass it to the new activity?
CustomerHomeFragment.java
public class CustomerHomeFragment extends Fragment {
private RecyclerView recyclerView;
private FoodsAdapter adapter;
private List<Food> foodList;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_home_customer, container, false);
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
recyclerView = view.findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
Call<FoodsResponse> call = RetrofitClient.getInstance().getApi().getFoods();
call.enqueue(new Callback<FoodsResponse>() {
#Override
public void onResponse(Call<FoodsResponse> call, Response<FoodsResponse> response) {
foodList = response.body().getFoods();
adapter = new FoodsAdapter(getActivity(), foodList);
recyclerView.setAdapter(adapter);
}
#Override
public void onFailure(Call<FoodsResponse> call, Throwable t) {
}
});
}
}
public class FoodsAdapter extends RecyclerView.Adapter implements View.OnClickListener{
private Context mCtx;
private List<Food> foodList;
public FoodsAdapter(Context mCtx, List<Food> foodList) {
this.mCtx = mCtx;
this.foodList = foodList;
}
#NonNull
#Override
public FoodsViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mCtx).inflate(R.layout.recyclerview_foods, parent, false);
return new FoodsViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull FoodsViewHolder holder, int position) {
Food food = foodList.get(position);
holder.textViewFName.setText(food.getFName());
holder.textViewUnitPrice.setText(String.format("%d", food.getUnitPrice()));
holder.textViewAvailCount.setText(String.format("%d", food.getAvailCount()));
}
#Override
public int getItemCount() {
return foodList.size();
}
//////////////
#Override
public void onClick(View view) {
Intent intent = new Intent(this.mCtx, AddOrderActivity.class);
this.mCtx.startActivity(intent);
}
/////////////////
class FoodsViewHolder extends RecyclerView.ViewHolder {
TextView textViewFName, textViewUnitPrice, textViewAvailCount;
public FoodsViewHolder(View itemView) {
super(itemView);
textViewFName = itemView.findViewById(R.id.textViewFName);
textViewUnitPrice = itemView.findViewById(R.id.textViewUnitPrice);
textViewAvailCount = itemView.findViewById(R.id.textViewAvailCount);
}
}
}
public class Food {
private int fid, unitprice, availcount;
private String fname;
public Food(int fid, String fname, int unitprice, int availcount) {
this.fid = fid;
this.fname = fname;
this.unitprice = unitprice;
this.availcount = availcount;
}
public int getFId() {
return fid;
}
public String getFName() {
return fname;
}
public int getUnitPrice() {
return unitprice;
}
public int getAvailCount() {
return availcount;
}
}

in the your adapter class inside the onBindViewHolder function add this code
viewHolder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent(context,NoteActivity.class);
intent.putExtra("note_id", currentNote.getNoteId());
intent.putExtra("note_name",currentNote.getNoteName());
intent.putExtra("note_teacher",currentNote.getNoteTeacher());
intent.putExtra("note_university",currentNote.getNoteUniversity());
intent.putExtra("note_image",currentNote.getNoteImage());
intent.putExtra("note_is_downloaded", currentNote.getIsDownloaded());
intent.putExtra("note_storage_path", currentNote.getStoragePath());
intent.putExtra("note_download_link", currentNote.getNoteDownloadLink());
context.startActivity(intent);
}
});

Firestore recyclerview

Hi i'm stuck on this part where i have 2 collections first one is users and second one is friends. I want my recyclerview to display my friends on the list with the help of current user because on currentUser other peoples id are stored and i want it to display it on the recyclerview but when it displays it i want to get their information from users where they have their username and email stored.
I want only friends collection ids to display on recyclerview with the help of current user id. Then i want to get values from users collection like their name and email value.
Friends collection
users collection
ADAPTER
public class FriendsAdapter extends FirestoreRecyclerAdapter {
private OnItemClicklistener onItemClicklistener;
public FriendsAdapter(#NonNull FirestoreRecyclerOptions<AllUsers> options) {
super(options);
}
#Override
protected void onBindViewHolder(#NonNull FriendsHolder holder, int position, #NonNull AllUsers model) {
holder.textViewUsername.setText(String.valueOf(model.getName()));
holder.textViewEmail.setText(model.getEmail());
holder.setAvatar(model.getAvatar());
}
#NonNull
#Override
public FriendsHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext())
.inflate(R.layout.all_user_list_display, viewGroup, false);
return new FriendsAdapter.FriendsHolder(view);
}
class FriendsHolder extends RecyclerView.ViewHolder {
TextView textViewUsername;
TextView textViewEmail;
ImageView imageViewAvatar;
public FriendsHolder(#NonNull View itemView) {
super(itemView);
textViewUsername = itemView.findViewById(R.id.all_user_username);
textViewEmail = itemView.findViewById(R.id.all_user_userEmail);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION && onItemClicklistener != null) {
onItemClicklistener.onItemClick(getSnapshots().getSnapshot(position), position);
}
}
});
}
public void setAvatar(String avatar) {
imageViewAvatar = (ImageView) itemView.findViewById(R.id.all_user_profile_image);
Picasso.get().load(avatar).into(imageViewAvatar);
}
}
public interface OnItemClicklistener {
void onItemClick(DocumentSnapshot snapshot, int position);
}
public void setOnItemClickListener(FriendsAdapter.OnItemClicklistener listener) {
onItemClicklistener = listener;
}
FriendListFragment
public class FriendsListFragment extends Fragment {
private FirebaseFirestore db;
private CollectionReference usersCollection;
private CollectionReference friendsCollection;
private DocumentReference friends;
private DocumentReference users;
private FirebaseUser current_user;
private FriendsAdapter adapter;
public SearchView search_friends;
public FriendsListFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_friends, container, false);
current_user = FirebaseAuth.getInstance().getCurrentUser();
//FIREBASE
db = FirebaseFirestore.getInstance();
usersCollection = db.collection("users");
friendsCollection = db.collection("friends");
friends = friendsCollection.document(current_user.getUid());
Query friendQuery = usersCollection;
FirestoreRecyclerOptions<AllUsers> options = new FirestoreRecyclerOptions.Builder<AllUsers>()
.setQuery(friendQuery, AllUsers.class)
.build();
adapter = new FriendsAdapter(options);
RecyclerView recyclerView = view.findViewById(R.id.friendsList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
recyclerView.setAdapter(adapter);
return view;
}
#Override
public void onStart() {
super.onStart();
adapter.startListening();
}
AllUsersClass
public class AllUsers {
public String name;
public String avatar;
public String email;
public String userId;
public AllUsers() {
}
public AllUsers(String name, String email, String avatar, String userId) {
this.name = name;
this.email = email;
this.avatar = avatar;
this.userId = userId;
}
public String getName() {
return name;
}
public String getAvatar() {
return avatar;
}
public String getEmail() {
return email;
}
public void setAvatar(String avatar) {
this.avatar = avatar;
}

FirebaseRecyclerAdapter not showing logs

I want to show a list of group chats in a TabLayout fragment. So, in order to do that, I used FirebaseRecyclerAdapter as my adapter and put it on RecyclerView.
These are my dependencies:
implementation 'com.firebaseui:firebase-ui-database:4.1.0'
implementation 'com.google.firebase:firebase-database:16.0.1'
implementation 'com.google.firebase:firebase-core:16.0.1'
implementation 'com.android.support:support-v4:27.1.1
This is my firebase database structure
This is my model:
public class ChatConv {
private String image, last_msg, name, online_status;
public ChatConv() {
}
public ChatConv(String image, String last_msg, String name, String online_status) {
this.image = image;
this.last_msg = last_msg;
this.name = name;
this.online_status = online_status;
}
public String getImage() {
return image;
}
public void setImage(String image) {
this.image = image;
}
public String getLast_msg() {
return last_msg;
}
public void setLast_msg(String last_msg) {
this.last_msg = last_msg;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getOnline_status() {
return online_status;
}
public void setOnline_status(String online_status) {
this.online_status = online_status;
}
}
I have created an adapter class that extends the FirebaseRecyclerAdapter and this is my code:
public class ChatConvAdapter extends FirebaseRecyclerAdapter<ChatConv, ChatConvAdapter.ViewHolder> {
private static final String TAG = "ChatConvAdapter";
public ChatConvAdapter(#NonNull FirebaseRecyclerOptions<ChatConv> options) {
super(options);
}
#Override
protected void onBindViewHolder(#NonNull ViewHolder holder, int position, #NonNull ChatConv model) {
holder.bind(model);
Log.i(TAG, "onBind is called");
Log.i(TAG, "name= " + model.getName());
Log.i(TAG, "msg= " + model.getLast_msg());
Log.i(TAG, "image= " + model.getImage());
}
#NonNull
#Override
public ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.row_item_global_list, parent, false);
Log.i(TAG, "onCreate is called");
return new ViewHolder(view);
}
class ViewHolder extends RecyclerView.ViewHolder {
#BindView(R.id.item_image)
CircleImageView imageView;
#BindView(R.id.item_name)
TextView nameView;
#BindView(R.id.item_desc)
TextView msgView;
#BindView(R.id.item_time)
TextView timeView;
ViewHolder(View itemView) {
super(itemView);
ButterKnife.bind(this, itemView);
}
public void bind(ChatConv chatConv) {
String name = chatConv.getName();
String image = chatConv.getImage();
String msg = chatConv.getLast_msg();
nameView.setText(name);
msgView.setText(msg);
Picasso.get().load(image).noFade().into(imageView);
}
}
}
In my fragment, I initialized my adapter and set the adapter inside the onCreateView()
#Override
public View onCreateView(#NonNull LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.layout_chat_list, container, false);
unbinder = ButterKnife.bind(this, view);
initObjects();
setUpRecyclerView();
setUpAdapter();
return view;
}
private void setUpAdapter() {
Query query = mWorldChatRef.orderByKey();
FirebaseRecyclerOptions<ChatConv> options = new FirebaseRecyclerOptions.Builder<ChatConv>()
.setQuery(query, ChatConv.class).build();
mAdapter = new ChatConvAdapter(options);
listChatView.setAdapter(mAdapter);
}
And startListening/stopListening in onStart()/onStop();
#Override
public void onStart() {
super.onStart();
mAdapter.startListening();
}
#Override
public void onStop() {
super.onStop();
mAdapter.stopListening();
}
I've searched for the possible answer here in StackOverflow but it didn't work for my case. Why am not getting logs? Am I missing something?

I have found my own solution by adding this line to the class that extends Application.
#Override
public void onCreate() {
super.onCreate();
Timber.plant(new Timber.DebugTree());
FirebaseDatabase instance = FirebaseDatabase.getInstance();
instance.setPersistenceEnabled(true);
}

Parse Objects Not Showing In RecyclerView

I am trying to fetch data from my Parse database and display it into a RecyclerView. From my knowledge I cannot see what I have done wrong and when I run the app not errors occur, and when opening this very fragment the app doesn't crash just shows a blank screen.
Any idea what is the problem?
Businesses
package zafir.com.app;
import com.parse.ParseClassName;
import com.parse.ParseObject;
#ParseClassName("Businesses")
public class Businesses extends ParseObject
{
private String Name;
public String getName()
{
return getString("Name");
}
public void setName(String name)
{
put("Name", name);
}
public String getCategory()
{
return getString("Category");
}
public void setCategory(String category)
{
put("Category", category);
}
public String getEmail()
{
return getString("Email");
}
public void setEmail(String email)
{
put("Email", email);
}
public String getLocation()
{
return getString("Location");
}
public void setLocation(String location)
{
put("Location", location);
}
public String getPhone()
{
return getString("Phone");
}
public void setPhone(String phone)
{
put("Phone", phone);
}
public String getWebsite()
{
return getString("Website");
}
public void setWebsite(String website)
{
put("Website", website);
}
}
RecyclerAdapter
public static class ViewHolder extends RecyclerView.ViewHolder
{
public TextView zName;
public TextView zPhone;
public TextView zEmail;
public TextView zWebsite;
public TextView zLocation;
public TextView zCategory;
public ViewHolder(View itemView)
{
super(itemView);
zName = (TextView) itemView.findViewById(R.id.name);
zPhone = (TextView) itemView.findViewById(R.id.phone);
zEmail = (TextView) itemView.findViewById(R.id.email);
zWebsite = (TextView) itemView.findViewById(R.id.website);
zLocation = (TextView) itemView.findViewById(R.id.location);
zCategory = (TextView) itemView.findViewById(R.id.category);
}
}
public RecyclerAdapter(Context context,List<Businesses> data)
{
inflater=LayoutInflater.from(context);
this.data= data;
}
#Override
public RecyclerAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
Context context = parent.getContext();
LayoutInflater inflater = LayoutInflater.from(context);
View recView = inflater.inflate(R.layout.recycler_layout, parent, false);
ViewHolder ViewHolder = new ViewHolder(recView);
return ViewHolder;
}
#Override
public void onBindViewHolder(RecyclerAdapter.ViewHolder viewHolder, int position)
{
Businesses businesses = data.get(position);
TextView name = viewHolder.zName;
name.setText(businesses.getName());
TextView phone = viewHolder.zPhone;
phone.setText(businesses.getPhone());
TextView email = viewHolder.zEmail;
email.setText(businesses.getEmail());
TextView website = viewHolder.zWebsite;
website.setText(businesses.getWebsite());
TextView location = viewHolder.zLocation;
location.setText(businesses.getLocation());
TextView category = viewHolder.zCategory;
category.setText(businesses.getCategory());
}
#Override
public int getItemCount()
{
return data.size();
}
}
Categories(Fragment)
public class Categories extends Fragment
{
List<Businesses> data = new ArrayList<>();
private RecyclerView zRecyclerView;
private RecyclerAdapter zAdapter;
private RecyclerView.LayoutManager zLayoutManager;
public Categories()
{
// Required empty public constructor
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable
Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.fragment_categories,container, false);
zRecyclerView = (RecyclerView) rootView.findViewById(R.id.recview_categories);
zRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
getData();
return super.onCreateView(inflater, container, savedInstanceState);
}
public void getData()
{
final List<Businesses> data = new ArrayList<>();
ParseQuery<Businesses> query = new ParseQuery<>("Businesses");
query.findInBackground(new FindCallback<Businesses>()
{
#Override
public void done(List<Businesses> list, ParseException e)
{
if(e == null)
{
for(Businesses businesses : list)
{
Businesses bizList = new Businesses();
bizList.setNames(businesses.getNames());
bizList.setPhone(businesses.getPhone());
bizList.setEmail(businesses.getEmail());
bizList.setWebsite(businesses.getWebsite());
bizList.setLocation(businesses.getLocation());
bizList.setCategory(businesses.getCategory());
data.add(bizList);
}
zAdapter = new RecyclerAdapter(getActivity(), data);
zRecyclerView.setAdapter(zAdapter);
}
}
});
}
}

Everything looks good. You just have to call notifyDataSetChanged() on zAdapter whenever you are changing the data. So change your code like this:
zAdapter = new RecyclerAdapter(getActivity(), data);
zRecyclerView.setAdapter(zAdapter);
zAdapter.notifyDataSetChanged();