Develop Reference

When I Enable Slider in Adapter Last position not showing (SLIDER_VIEW merge with ITEM_VIEW )

Need to Show Slider With a missing fisrt position of ITEM_VIEW
Check IMAGE 1
When Slider Enabled Don't Showing first position of ITEM_VIEW (Issue is SLIDER_VIEW position merge with ITEM_VIEW position). Need to show ITEM_VIEW missing first position With Slider
Check IMAGE 2
When Slider Not Enabled ITEM_VIEW first position Showing
public class WallpapersAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private static final int ITEM_VIEW = 0;
private static final int AD_VIEW = 1;
private static final int SLIDER_VIEW = 2;
public static SharedPreferences sharedPreferences;
final long DELAY_MS = 500;//delay in milliseconds before task is to be executed
final long PERIOD_MS = 6000; // time in milliseconds between successive task executions.
private final Context mContext;
private final OnItemClickListener listener;
private final int itemLayout;
public List<Image> mData;
RequestOptions option;
SharedPref sharedPref;
String status;
List<SliderUtils> sliderImg;
ViewPagerAdapterSlider viewPagerAdapterSlider;
int currentPage = 1;
Timer timer;
private int dotscount;
private ImageView[] dots;
public WallpapersAdapter(Context mContext, List<Image> mData, OnItemClickListener listener) {
this.mContext = mContext;
this.mData = mData;
this.listener = listener;
this.itemLayout = R.layout.wallpaper_item;
// Request option for Glide
option = new RequestOptions().centerCrop();
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(mContext);
if (viewType == ITEM_VIEW) {
View view = layoutInflater.inflate(R.layout.wallpaper_item, parent, false);
return new MainViewHolder(view);
} else if (viewType == AD_VIEW) {
View view = layoutInflater.inflate(R.layout.item_native_ad, parent, false);
return new AdViewHolder(view);
} else if (viewType == SLIDER_VIEW) {
View view = layoutInflater.inflate(R.layout.custom_layout, parent, false);
return new SliderViewHolder(view);
} else {
return null;
}
}
#Override
public void onBindViewHolder(#NonNull RecyclerView.ViewHolder holder, int position) {
sharedPreferences = PreferenceManager.getDefaultSharedPreferences(mContext);
status = sharedPreferences.getString("status", "free");
StaggeredGridLayoutManager.LayoutParams layoutParams = (StaggeredGridLayoutManager.LayoutParams) holder.itemView.getLayoutParams();
if (holder.getItemViewType() == ITEM_VIEW) {
int pos = position - Math.round(position / Config.NATIVE_ADS_PER_ITEM);
((MainViewHolder) holder).bindData(mData.get(pos), listener, position);
} else if (holder.getItemViewType() == AD_VIEW) {
if (Config.ENABLE_ADS == true & status.equals("free")) {
((AdViewHolder) holder).bindAdData();
layoutParams.setFullSpan(getItemViewType(position) == AD_VIEW);
}
} else if (holder.getItemViewType() == SLIDER_VIEW) {
layoutParams.setFullSpan(getItemViewType(position) == SLIDER_VIEW);
((SliderViewHolder) holder).bindSliderData();
}
}
#Override
public int getItemCount() {
if (mData.size() > 0) {
return mData.size() + Math.round(mData.size() / Config.NATIVE_ADS_PER_ITEM);
}
return mData.size();
}
#Override
public int getItemViewType(int position) {
// Here position set 0 showing Slider But not showing last position
if ((position == 0) && Config.ENABLE_RECENT_SLIDER == true) {
return SLIDER_VIEW;
} else if ((position + 1) % Config.NATIVE_ADS_PER_ITEM == 0) {
return AD_VIEW;
}
return ITEM_VIEW;
}
private void sendRequest(ViewPager viewPagerForSlider, TextView textSlider) {
JsonObjectRequest request = new JsonObjectRequest(Request.Method.GET, Config.SM, null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
JSONArray ja_data = response.getJSONArray("slides");
Log.d("OHOHOH", String.valueOf(ja_data));
for (int i = 0; i < ja_data.length(); i++) {
SliderUtils sliderUtils = new SliderUtils();
try {
JSONObject jsonObject = ja_data.getJSONObject(i);
sliderUtils.setSliderImageUrl(jsonObject.getString("slider_image"));
sliderUtils.setUrl(jsonObject.getString("url"));
sliderUtils.setSlider_name(jsonObject.getString("slider_name"));
sliderUtils.setType(jsonObject.getString("slider_type"));
sliderUtils.setCat_id(jsonObject.getInt("cat_id"));
sliderUtils.setCollection(jsonObject.getString("collection"));
//textSlider.setText(jsonObject.getString("slider_name"));
} catch (JSONException e) {
e.printStackTrace();
}
sliderImg.add(sliderUtils);
}
viewPagerAdapterSlider = new ViewPagerAdapterSlider(sliderImg, mContext);
viewPagerForSlider.setAdapter(viewPagerAdapterSlider);
dotscount = viewPagerAdapterSlider.getCount();
dots = new ImageView[dotscount];
final Handler handler = new Handler();
final Runnable Update = new Runnable() {
public void run() {
if (currentPage == dotscount) {
currentPage = 0;
}
viewPagerForSlider.setCurrentItem(currentPage++, true);
}
};
timer = new Timer(); // This will create a new Thread
timer.schedule(new TimerTask() { // task to be scheduled
#Override
public void run() {
handler.post(Update);
}
}, DELAY_MS, PERIOD_MS);
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
MySingleton.getInstance(mContext).addToRequestQueue(request);
}
public interface OnItemClickListener {
void onItemClick(View view, Image mData, int position);
}
public class MainViewHolder extends RecyclerView.ViewHolder {
WallpaperItemBinding binding;
public MainViewHolder(#NonNull View itemView) {
super(itemView);
binding = WallpaperItemBinding.bind(itemView);
}
public void bindData(Image main, final OnItemClickListener listener, final int position) {
sharedPref = new SharedPref(mContext);
binding.wallpaperName.setText(main.getImage_name());
binding.viewCount.setText(main.getViews_count());
if (sharedPref.loadAmoled() == true) {
binding.constraintBg.setBackgroundColor(mContext.getResources().getColor(R.color.amoled_color_light));
}
sharedPref = new SharedPref(mContext);
}
}
public class AdViewHolder extends RecyclerView.ViewHolder {
ItemNativeAdBinding binding;
public AdViewHolder(#NonNull View itemView) {
super(itemView);
binding = ItemNativeAdBinding.bind(itemView);
}
#SuppressLint("MissingPermission")
private void bindAdData() {
final AdLoader adLoader = new AdLoader.Builder(mContext, mContext.getResources().getString(R.string.admob_native_id))
.forNativeAd(new NativeAd.OnNativeAdLoadedListener() {
#Override
public void onNativeAdLoaded(NativeAd ad) {
binding.admobNativeAdContainer.setNativeAd(ad);
}
}).build();
adLoader.loadAds(new AdRequest.Builder().build(), 3);
if (isNetworkConnected()) {
binding.admobNativeAdContainer.setVisibility(View.VISIBLE);
}
}
#SuppressLint("MissingPermission")
private boolean isNetworkConnected() {
ConnectivityManager cm = (ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE);
return cm.getActiveNetworkInfo() != null && cm.getActiveNetworkInfo().isConnected();
}
}
public class SliderViewHolder extends RecyclerView.ViewHolder {
CustomLayoutBinding customLayoutBinding;
public SliderViewHolder(View view) {
super(view);
customLayoutBinding = CustomLayoutBinding.bind(view);
}
public void bindSliderData() {
sliderImg = new ArrayList<>();
customLayoutBinding.viewPagerForSlider.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
#Override
public void onPageSelected(int position) {
customLayoutBinding.dotsIndicator.setViewPager(customLayoutBinding.viewPagerForSlider);
}
#Override
public void onPageScrollStateChanged(int state) {
}
});
sendRequest(customLayoutBinding.viewPagerForSlider, customLayoutBinding.textSlider);
}
}
}

RecyclerView won't load data retrieved from Firestore into ItemView

So, basically what I am trying to do is to show a bunch of Post type objects on my Android app's feed (HomeFragment). The posts are being successfully retrieved from Firestore (I did check the debugger) but somehow, not all of them get loaded in the recyclerView. The itemViewHolder is only loaded with how I defined it as an XML, fields filled with lore Ipsum.
This would be my code:
HomeFragment:
public class HomeFragment extends Fragment {
private RecyclerView recyclerView;
private RecyclerViewAdapter recyclerViewAdapter;
private boolean isLoading = false;
private ArrayList<String> rowsArrayList = new ArrayList<>();
public static ArrayList<Post> appliedToList = new ArrayList<>();
private User currentUser = new User();
private View root;
private TextView userState;
private FirebaseFirestore db = FirebaseFirestore.getInstance();
private String userId = FirebaseAuth.getInstance().getCurrentUser() != null ? FirebaseAuth.getInstance().getCurrentUser().getUid() : null;
public View onCreateView(#NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
root = inflater.inflate(R.layout.fragment_home, container, false);
setState();
appliedToPostsRetrieverFromHomePage(getContext());
checkForPostFragment();
recyclerView = root.findViewById(R.id.recyclerView);
initAdapter();
initScrollListener();
return root;
}
private void initAdapter() {
recyclerViewAdapter = new RecyclerViewAdapter(getActivity(), 2);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
recyclerView.setAdapter(recyclerViewAdapter);
}
private void initScrollListener() {
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(#NonNull RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
#Override
public void onScrolled(#NonNull RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
LinearLayoutManager linearLayoutManager = (LinearLayoutManager) recyclerView.getLayoutManager();
if (!isLoading) {
if (linearLayoutManager != null && linearLayoutManager.findLastCompletelyVisibleItemPosition() == rowsArrayList.size() - 1) {
//bottom of list!
loadMore();
isLoading = true;
}
}
}
});
}
private void loadMore() {
rowsArrayList.add(null);
recyclerViewAdapter.notifyItemInserted(rowsArrayList.size() - 1);
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
rowsArrayList.remove(rowsArrayList.size() - 1);
int scrollPosition = rowsArrayList.size();
recyclerViewAdapter.notifyItemRemoved(scrollPosition);
int currentSize = scrollPosition;
int nextLimit = currentSize + 10;
while (currentSize - 1 < nextLimit) {
rowsArrayList.add("Item " + currentSize);
currentSize++;
}
recyclerViewAdapter.notifyDataSetChanged();
isLoading = false;
}
}, 2000);
}
#Override
public void onAttachFragment(#NonNull Fragment fragment) {
super.onAttachFragment(fragment);
}
RecyclerViewAdapter:
All view types represent kind of the same layout, the only difference between them is what is wrote on a certain button. Remember, some of the posts are successfully loaded!
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private final int VIEW_TYPE_APPLY = 0;
private final int VIEW_TYPE_MORE = 1;
private final int VIEW_TYPE_BEGIN = 2;
private final int VIEW_TYPE_PENDING = 3;
private final int VIEW_TYPE_END = 4;
private final int VIEW_TYPE_ON_GOING = 5;
private final int VIEW_TYPE_LOADING = 6;
private ArrayList<Post> list = new ArrayList();
private static final String TAG = RecyclerViewAdapter.class.getSimpleName();
private Context context;
private User currentUser;
private int recyclerType;
static ArrayList<User> applicantsList = new ArrayList<>();
private String userId = FirebaseAuth.getInstance().getCurrentUser() != null ? FirebaseAuth.getInstance().getCurrentUser().getUid() : null;
private FirebaseFirestore db = FirebaseFirestore.getInstance();
public RecyclerViewAdapter(Context context, int recyclerType) {
this.context = context;
this.recyclerType = recyclerType;
if (recyclerType == 0) {
myPostsRetriever(context);
} else if (recyclerType == 1) {
appliedToPostsRetriever(context);
} else if (recyclerType == 2) {
homePostsRetriever(context);
}
}
#NonNull
#Override
public RecyclerView.ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
if (viewType == VIEW_TYPE_APPLY) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row_apply, parent, false);
return new ItemViewHolder(view);
} else if (viewType == VIEW_TYPE_MORE) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row_more, parent, false);
return new LoadingViewHolder(view);
} else if (viewType == VIEW_TYPE_BEGIN) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row_begin, parent, false);
return new LoadingViewHolder(view);
} else if (viewType == VIEW_TYPE_PENDING) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row_pending, parent, false);
return new LoadingViewHolder(view);
} else if (viewType == VIEW_TYPE_END) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row_end, parent, false);
return new LoadingViewHolder(view);
} else if (viewType == VIEW_TYPE_ON_GOING) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row_on_going, parent, false);
return new LoadingViewHolder(view);
} else {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_loading, parent, false);
return new LoadingViewHolder(view);
}
}
#Override
public void onBindViewHolder(#NonNull RecyclerView.ViewHolder viewHolder, int position) {
if (viewHolder instanceof ItemViewHolder) {
populateItemRows((ItemViewHolder) viewHolder, position);
} else if (viewHolder instanceof LoadingViewHolder) {
showLoadingView((LoadingViewHolder) viewHolder, position);
}
}
#Override
public int getItemCount() {
return list == null ? 0 : list.size();
}
#Override
public int getItemViewType(int position) {
if (list.get(position) != null) {
if (!list.get(position).getOwner().equals(userId) &&
!checkIfAlreadyAppliedToPost(position) &&
list.get(position).getMinNeededPersons() >= list.get(position).getApplicants()) {
return VIEW_TYPE_APPLY;
} else if (recyclerType == 1) {
return VIEW_TYPE_MORE;
} else if (list.get(position).getOwner().equals(userId) && timeCheck(list.get(position))) {
return VIEW_TYPE_BEGIN;
} else if (list.get(position).getOwner().equals(userId) && checkIfStarted(position)
|| !list.get(position).getOwner().equals(userId) && checkIfAlreadyAppliedToPost(position) && !checkIfStarted(position)) {
return VIEW_TYPE_PENDING;
} else if (list.get(position).getOwner().equals(userId) && checkIfStarted(position)) {
return VIEW_TYPE_END;
} else if (!list.get(position).getOwner().equals(userId) && checkIfStarted(position)){
return VIEW_TYPE_ON_GOING;
}else if (list.get(position).getOwner().equals(userId))
return VIEW_TYPE_MORE;
}
return VIEW_TYPE_LOADING;
}
private class ItemViewHolder extends RecyclerView.ViewHolder {
TextView title;
TextView description;
TextView location;
TextView minNeededPersons;
TextView maxNeededPersons;
TextView reward;
TextView time;
CheckBox physical;
Button button;
ItemViewHolder(#NonNull View itemView) {
super(itemView);
title = itemView.findViewById(R.id.postTitle);
description = itemView.findViewById(R.id.postDescription);
location = itemView.findViewById(R.id.postLocationText);
time = itemView.findViewById((R.id.postDateAndTime));
minNeededPersons = itemView.findViewById(R.id.people);
maxNeededPersons = itemView.findViewById(R.id.people);
reward = itemView.findViewById(R.id.reward);
physical = itemView.findViewById(R.id.checkBox2);
button = itemView.findViewById(R.id.applyButton);
}
}
private class LoadingViewHolder extends RecyclerView.ViewHolder {
ProgressBar progressBar;
LoadingViewHolder(#NonNull View itemView) {
super(itemView);
progressBar = itemView.findViewById(R.id.progressBar);
}
}
private void showLoadingView(LoadingViewHolder viewHolder, int position) {
}
private void populateItemRows(ItemViewHolder viewHolder, int position) {
Post item = list.get(position);
viewHolder.title.setText(item.getTheTitle());
viewHolder.description.setText(item.getDescription());
viewHolder.location.setText(item.getLocation());
viewHolder.location.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent showLocation = new Intent(context, MapsActivity.class);
context.startActivity(showLocation);
}
});
viewHolder.minNeededPersons.setText(String.valueOf(item.getMinNeededPersons()));
viewHolder.maxNeededPersons.setText(String.valueOf(item.getMaxPersonsNeeded()));
viewHolder.reward.setText(String.valueOf(item.getReward()));
viewHolder.physical.setChecked(item.isPhysical());
Date timeAndDate = item.getTime().toDate();
viewHolder.time.setText(new SimpleDateFormat("HH:mm dd.MM.yyyy").format(timeAndDate));
viewHolder.button.setOnClickListener(new View.OnClickListener() {
#SuppressLint("SetTextI18n")
#Override
public void onClick(View v) {
if (viewHolder.button.getText().equals(context.getResources().getString(R.string.apply))) {
onApplyTapped(position);
viewHolder.button.setText(R.string.pending);
viewHolder.button.setBackgroundColor(Color.parseColor("#F2CF59"));
viewHolder.button.setClickable(false);
} else if (viewHolder.button.getText().equals(context.getResources().getString(R.string.begin_job))) {
onBeginTapped(position);
viewHolder.button.setText(R.string.end_job);
viewHolder.button.setBackgroundColor(Color.parseColor("#F8CA9D"));
} else if (viewHolder.button.getText().equals(context.getResources().getString(R.string.end_job))) {
onEndTapped(position);
viewHolder.button.setBackgroundColor(Color.parseColor("#FB8E7E"));
viewHolder.button.setClickable(false);
viewHolder.button.setText(R.string.finished);
}
}
});
viewHolder.itemView.findViewById(R.id.seePostButton).setOnClickListener(new View.OnClickListener()
{ not relevant }
private void homePostsRetriever(Context context) {
FirebaseFirestore rootRef = FirebaseFirestore.getInstance();
rootRef.collectionGroup("posts").limit(10).get().addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
#Override
public void onSuccess(QuerySnapshot documentSnapshots) {
for (DocumentSnapshot documentSnapshot : documentSnapshots.getDocuments()) {
Post post = new Post();
post.setAvailability(documentSnapshot.getBoolean("available"));
post.setTitle(documentSnapshot.getString("title"));
post.setDescription(documentSnapshot.getString("description"));
post.setLocation(documentSnapshot.getString("location"));
post.setApplicants(documentSnapshot.getLong("applicants").intValue());
post.setOwner(documentSnapshot.getString("owner"));
post.setMinNeededPersons(documentSnapshot.getLong("minNrOfPeople").intValue());
post.setMaxPersonsNeeded(documentSnapshot.getLong("maxNrOfPeople").intValue());
post.setReward(Objects.requireNonNull(documentSnapshot.getLong("reward")).floatValue());
post.setPhysical(documentSnapshot.getBoolean("physicalExcertion"));
post.setTime(documentSnapshot.getTimestamp("time"));
post.setId(documentSnapshot.getId());
post.setStarted(documentSnapshot.getBoolean("started"));
list.add(post);
}
notifyDataSetChanged();
}
}).addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Toast.makeText(context, "No document found", Toast.LENGTH_SHORT).show();
}
});
}

I don't think you are calling bind methods correctly, try:
#Override
public void onBindViewHolder(#NonNull RecyclerView.ViewHolder viewHolder, int position) {
if (viewHolder instanceof ItemViewHolder) {
ItemViewHolder holder = (ItemViewHolder)viewHolder;
holder.populateItemRows(holder, position);
} else if (viewHolder instanceof LoadingViewHolder) {
LoadingViewHolder holder = (LoadingViewHolder)viewHolder;
holder.showLoadingView(holder , position);
}
}
Also this method:
private void populateItemRows(ItemViewHolder viewHolder, int position) {
.....
....
....
}
Is not found in your ItemViewHolder class

Pagination not working properly Android. It is showing all item at a time

I have recyclerview with 30 items in it. When i try to scroll pagination is not working. It is showing all items instead of refreshing. Below is my code.
public class InstitutesWithSearchActivity extends AppCompatActivity {
PaginationAdapter adapter;
private static final int PAGE_START = 1;
private boolean isLoading, isLastPage = false;
private int TOTAL_PAGES = 2;
int itemCount = 0;
private int currentPage = PAGE_START;
ApiInterface apiInterface;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
adapter = new PaginationAdapter(this);
layoutManager = new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false);
recyclerView.setLayoutManager(layoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.setAdapter(adapter);
recyclerView.addOnScrollListener(new PaginationScrollListener(layoutManager) {
#Override
protected void loadMoreItems() {
isLoading = true;
currentPage += 1;
//mocking network delay for api
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
loadNextPage();
}
},2000);
}
#Override
public int getTotalPageCount() {
return TOTAL_PAGES;
}
#Override
public boolean isLastPage() {
return isLastPage;
}
#Override
public boolean isLoading() {
return isLoading;
}
});
//init service and load data
apiInterface = ApiClient.getClient().create(ApiInterface.class);
loadFirstPage();
}
private void loadNextPage() {
Call<InstituteResponseModel> call = apiInterface.masterInstitutes();
call.enqueue(new Callback<InstituteResponseModel>() {
#Override
public void onResponse(Call<InstituteResponseModel> call, Response<InstituteResponseModel> response) {
adapter.removeLoadingFooter();
isLoading = false;
ArrayList<InstituteModel> results = fetchResults(response);
adapter.addAll(results);
if (currentPage != PAGE_START) adapter.removeLoadingFooter();
adapter.addAll(results);
if (currentPage < TOTAL_PAGES) adapter.addLoadingFooter();
else isLastPage = true;
isLoading = false;
}
#Override
public void onFailure(Call<InstituteResponseModel> call, Throwable t) {
t.printStackTrace();
}
});
}
private void loadFirstPage() {
Log.e(TAG,"loadFirstPage");
Call<InstituteResponseModel> call = apiInterface.masterInstitutes();
call.enqueue(new Callback<InstituteResponseModel>() {
#Override
public void onResponse(Call<InstituteResponseModel> call, Response<InstituteResponseModel> response) {
ArrayList<InstituteModel> results = fetchResults(response);
progressBar.setVisibility(View.GONE);
adapter.addAll(results);
if (currentPage <= TOTAL_PAGES) adapter.addLoadingFooter();
else isLastPage = true;
}
#Override
public void onFailure(Call<InstituteResponseModel> call, Throwable t) {
t.printStackTrace();
}
});
}
private ArrayList<InstituteModel> fetchResults(Response<InstituteResponseModel> response) {
InstituteResponseModel responseModel = response.body();
return responseModel.getData();
}
}
I don't know what is the mistake from my side. I'm new to this pagination concept. I'm getting example code which uses forloop to show data. I'm using API to show data in Recyclerview.
public class PaginationAdapter extends RecyclerView.Adapter {
private static final int ITEM = 0;
private static final int LOADING = 1;
boolean isLoadingAdded = false;
private ArrayList<InstituteModel> modelArrayList;
Context context;
public PaginationAdapter(Context context) {
this.context = context;
modelArrayList = new ArrayList<>();
}
public ArrayList<InstituteModel> getInstitutes() {
return modelArrayList;
}
public void setInstitutes(ArrayList<InstituteModel> modelArrayList) {
this.modelArrayList = modelArrayList;
}
#NonNull
#Override
public RecyclerView.ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
RecyclerView.ViewHolder viewHolder = null;
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
switch (viewType){
case ITEM:
viewHolder = getViewHolder(parent, inflater);
break;
case LOADING:
View v2 = inflater.inflate(R.layout.item_progress, parent, false);
viewHolder = new LoadingVH(v2);
break;
}
return viewHolder;
}
private RecyclerView.ViewHolder getViewHolder(ViewGroup parent, LayoutInflater inflater){
RecyclerView.ViewHolder viewHolder;
View v1 = inflater.inflate(R.layout.institute_row_layout, parent, false);
viewHolder = new InstituteHolder(v1);
return viewHolder;
}
#Override
public void onBindViewHolder(#NonNull RecyclerView.ViewHolder holder, int parent) {
InstituteModel model = modelArrayList.get(parent);
switch (getItemViewType(parent)){
case ITEM:
final InstituteHolder instituteHolder = (InstituteHolder) holder;
instituteHolder.instName.setText(model.getInstituteName());
Glide.with(context)
.load(model.getImageURL())
.listener(new RequestListener<String, GlideDrawable>() {
#Override
public boolean onException(Exception e, String model, Target<GlideDrawable> target, boolean isFirstResource) {
instituteHolder.progressBar.setVisibility(GONE);
return false;
}
#Override
public boolean onResourceReady(GlideDrawable resource, String model, Target<GlideDrawable> target, boolean isFromMemoryCache, boolean isFirstResource) {
instituteHolder.progressBar.setVisibility(GONE);
return false;
}
})
.diskCacheStrategy(DiskCacheStrategy.ALL)
.centerCrop()
.crossFade()
.into(instituteHolder.instImg);
break;
case LOADING:
break;
}
}
#Override
public int getItemCount() {
return modelArrayList == null ? 0 : modelArrayList.size();
}
#Override
public int getItemViewType(int position) {
return (position == modelArrayList.size()-1 && isLoadingAdded) ? LOADING : ITEM;
}
public void add(InstituteModel m){
modelArrayList.add(m);
notifyItemInserted(modelArrayList.size()-1);
}
public void addAll(ArrayList<InstituteModel> modelsList){
for (InstituteModel model : modelsList){
add(model);
}
}
public void remove(InstituteModel model){
int position = modelArrayList.indexOf(model);
if (position > -1){
modelArrayList.remove(position);
notifyItemRemoved(position);
}
}
public void clear(){
isLoadingAdded = false;
while (getItemCount()>0){
remove(getItem(0));
}
}
public boolean isEmpty(){
return getItemCount() == 0;
}
public void addLoadingFooter(){
isLoadingAdded = true;
add(new InstituteModel());
}
public void removeLoadingFooter(){
isLoadingAdded = false;
int position = modelArrayList.size() -1;
InstituteModel result = getItem(position);
if (result != null){
modelArrayList.remove(position);
notifyItemRemoved(position);
}
}
public InstituteModel getItem(int position){return modelArrayList.get(position);}
protected class InstituteHolder extends RecyclerView.ViewHolder {
TextView instName;
ImageView instImg;
TextView cityName, areaName;
RelativeLayout cardView;
ProgressBar progressBar;
public InstituteHolder(#NonNull View itemView) {
super(itemView);
instImg = itemView.findViewById(R.id.course_image);
instName = itemView.findViewById(R.id.course_name);
areaName = itemView.findViewById(R.id.course_area);
cityName = itemView.findViewById(R.id.course_city);
progressBar = itemView.findViewById(R.id.imgProgress);
cardView = itemView.findViewById(R.id.cardView);
}
}
protected class LoadingVH extends RecyclerView.ViewHolder {
public LoadingVH(#NonNull View itemView) {
super(itemView);
}
}
}

Error while displaying items in RecyclerView with Multiple ViewTypes

I am using Recyclerview with multiple ViewTypes.I have two Model classes for two different type of item in recyclerview as.I want to display two different type of item in same RecyclerView
My RecyclerViewAdapter is
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private Context context;
ArrayList<OneView> oneList;
ArrayList<TwoView> twoList;
public RecyclerAdapter(Context context,ArrayList<OneView> oneList,ArrayList<TwoView> twoList){
this.context=context;
this.oneList=oneList;
this.twoList=twoList;
}
#Override
public int getItemViewType(int position) {
switch (position){
case 0:
return 0;
case 1:
return 1;
}
return -1;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
int layout=0;
RecyclerView.ViewHolder viewHolder;
if(viewType==0){
layout=R.layout.oneview;
View one= LayoutInflater.from(parent.getContext()).inflate(layout,parent,false);
return new ViewHolder(one);
}else if(viewType==1){
layout=R.layout.twoview;
View two= LayoutInflater.from(parent.getContext()).inflate(layout,parent,false);
return new SecondView(two);
}else {
return null;
}
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
int viewType=holder.getItemViewType();
switch (viewType){
case 0:
OneView oneView=oneList.get(position);
((ViewHolder)holder).name.setText(oneView.getName());
break;
case 1:
TwoView twoView=twoList.get(position);
((SecondView)holder).name.setText(twoView.getName());
((SecondView)holder).address.setText(twoView.getAddress());
break;
default:
break;
}
}
#Override
public int getItemCount() {
return (this.oneList.size()+this.twoList.size());
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView name;
public ViewHolder(View itemView) {
super(itemView);
name=(TextView)itemView.findViewById(R.id.nameOne);
}
}
public class SecondView extends RecyclerView.ViewHolder {
private TextView name,address;
public SecondView(View itemView) {
super(itemView);
name=(TextView)itemView.findViewById(R.id.nameTwo);
address=(TextView)itemView.findViewById(R.id.address);
}
}
}
I want to display two type of item in same RecyclerView.But I am getting Attempt to write to field 'int android.support.v7.widget.RecyclerView$ViewHolder.mItemViewType' on a null object reference exception. How to resolve this ?

here is the complete example. I've used a RecyclerView with Multiple View Type. My scenario was, I have to show "cuisine list" [which is a horizontal view of multiple cuisines], then "number of restaurant", then "restaurant list".
so, i've used VIEW_RESTAURANT for restaurant view, VIEW_CUISINE for cuisine, VIEW_INFO for number of restaurant. As for my case, there's pagination, so VIEW_PROGRESS is used for showing progress bar at the bottom [by that time new set of data is fetch, if avaiable], VIEW_NO_DATA is used if restaurant list is empty.
hopefully from here, You can manage based on your requirement.
public class HomeAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private String TAG = HomeAdapter.class.getSimpleName();
class ViewType {
int VIEW_PROGRESS = 1;
int VIEW_NO_DATA = 2;
int VIEW_RESTAURANT = 3;
int VIEW_CUISINE = 4;
int VIEW_INFO = 6;
}
private ViewType mViewType = new ViewType();
private Context mContext;
private int mCuisineItem = 1;
private int mInfoItem = 1;
private int mShowNoItem = 0;
private boolean mIsLoading;
private int mRestaurantNumber;
private int mCurrentPage;
private List<Data> mDataList;
private List<CuisineData> mCuisines;
private PaginationListener mPaginationListener;
private HorizontalPaginationListener mHorizontalPaginationListener;
private SearchResultClickListener mSearchResultClickListener;
private String mFrom;
public HomeAdapter(Context context, List<Data> dataList, List<CuisineData> cuisines, RecyclerView recyclerView, SearchResultClickListener searchResultClickListener) {
mContext = context;
mDataList = dataList;
mCuisines = cuisines;
mSearchResultClickListener = searchResultClickListener;
if (recyclerView.getLayoutManager() instanceof LinearLayoutManager) {
final LinearLayoutManager llManager = (LinearLayoutManager) recyclerView.getLayoutManager();
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int visible_threshold = 1;
int total_item_count = llManager.getItemCount();
int last_visible_item = llManager.findLastVisibleItemPosition();
if (!mIsLoading && total_item_count <= (last_visible_item + visible_threshold)) {
if (mPaginationListener != null) mPaginationListener.onPagination();
mIsLoading = true;
}
}
});
}
}
public void setmPaginationListener(PaginationListener paginationListener) {
mPaginationListener = paginationListener;
}
public void setmHorizontalPaginationListener(HorizontalPaginationListener horizontalPaginationListener) {
mHorizontalPaginationListener = horizontalPaginationListener;
}
public void setLoaded() {
mIsLoading = false;
}
public void setmRestaurantNumber(int restaurantNumber) {
mRestaurantNumber = restaurantNumber;
}
public void setmCurrentPage(int currentPage) {
mCurrentPage = currentPage;
}
public void addCuisine(String from) {
mFrom = from;
notifyDataSetChanged();
}
public void addCuisines(List<CuisineData> cuisines, String from) {
mFrom = from;
mCuisines.clear();
mCuisines = cuisines;
notifyDataSetChanged();
}
public void addRestaurants(List<Data> dataList) {
mShowNoItem = 0;
if(mCurrentPage == 1) notifyItemChanged(1);
if (mCurrentPage == 1) notifyItemChanged(2);
int insert_index = mDataList.size();
int pos_start = insert_index + mCuisineItem + mInfoItem;
mDataList.addAll(insert_index, dataList);
notifyItemRangeInserted(pos_start, dataList.size());
}
public void removeRestaurants() {
mShowNoItem = 1;
mDataList.clear();
mDataList = new ArrayList<>();
notifyItemRangeRemoved(mCuisineItem + mInfoItem, mDataList.size());
notifyItemChanged(2);
}
public void addProgressBar(Data data) {
mDataList.add(data);
notifyItemInserted(getItemCount() - 1);
}
public void removeProgressBar() {
if (mDataList.size() > 0) {
mDataList.remove(mDataList.size() - 1);
notifyItemRemoved(mCuisineItem + mInfoItem + mDataList.size());
}
}
public void removeAll() {
mDataList.clear();
mCuisines.clear();
mShowNoItem = 0;
notifyDataSetChanged();
}
#Override
public int getItemCount() {
return mDataList.size() + mShowNoItem + mCuisineItem + mInfoItem;
}
#Override
public int getItemViewType(int position) {
if (position == 0) return mViewType.VIEW_CUISINE;
if (position == 1) return mViewType.VIEW_INFO;
return mShowNoItem == 0 ? (mDataList.get(position - (mCuisineItem + mInfoItem)) != null ? mViewType.VIEW_RESTAURANT : mViewType.VIEW_PROGRESS)
: mViewType.VIEW_NO_DATA;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == mViewType.VIEW_CUISINE) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_horizontal_cuisines, parent, false);
return new ViewHolderCuisinesList(mContext, view, mHorizontalPaginationListener);
}
if (viewType == mViewType.VIEW_INFO) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_restaurant_number, parent, false);
return new ViewHolderRestaurantNumber(mContext, view);
}
if (mShowNoItem == 0) {
if (viewType == mViewType.VIEW_RESTAURANT) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.food_item_nearest_restaurant, parent, false);
return new ViewHolderRestaurant(mContext, view, mSearchResultClickListener);
} else if (viewType == mViewType.VIEW_PROGRESS) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_progress, parent, false);
return new ViewHolderProgress(view);
}
} else {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_empty, parent, false);
return new ViewHolderEmpty(view);
}
return null;
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if (holder instanceof ViewHolderSearch) {
((ViewHolderSearch) holder).onBind();
}
if (holder instanceof ViewHolderCuisinesList) {
if (!TextUtils.isEmpty(mFrom)) {
if (mFrom.equalsIgnoreCase(AppConstants.CUISINES))
((ViewHolderCuisinesList) holder).onBind(mCuisines);
else if (mFrom.equalsIgnoreCase(AppConstants.CUISINE))
((ViewHolderCuisinesList) holder).onBind_();
}
}
if (holder instanceof ViewHolderRestaurantNumber) {
((ViewHolderRestaurantNumber) holder).onBind(mRestaurantNumber);
}
if (mShowNoItem == 0) {
if (holder instanceof ViewHolderRestaurant) {
((ViewHolderRestaurant) holder).onBind(position - (mCuisineItem + mInfoItem), mDataList.get(position - (mCuisineItem + mInfoItem)));
} else if (holder instanceof ViewHolderProgress) {
((ViewHolderProgress) holder).onBind();
}
} else {
if (holder instanceof ViewHolderEmpty) {
((ViewHolderEmpty) holder).onBind(mContext.getString(R.string.no_result_found));
}
}
}
}

Add ProgressBar when recyclerView hit scroll

I have to add Pagination in recyclerView. But I am stuck in adding a progressbar when recyclerView scroll.
I have been trying for a day but unfortunately not got a valid solution to add a progress bar at run time while recyclerView scrolling.I have three ViewHolder.
RecyclerView Scroll Listener
rvRewardItems.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int visibleItemCount = recyclerView.getChildCount();
int totalItemCount = wrapperLinearLayout.getItemCount();
int firstVisibleItem = wrapperLinearLayout.findFirstVisibleItemPosition();
int lastInScreen = firstVisibleItem + visibleItemCount;
if ((lastInScreen == totalItemCount) && !isLoadingMore) {
if (!mStopLoadingData) {
try {
isLoadingMore = true;
// Add item for progress ba
new Handler().post(new Runnable() {
#Override
public void run() {
adapter.addProgressView();
}
});
loadReviews(false, false);
}catch (IllegalStateException e){
e.printStackTrace();
}
}
}
}
});
RewardFinalAdapter.class
public class RewardFinalAdapter extends RecyclerView.Adapter<MainViewHolder>
{
private Context context;
private ArrayList<RewardItemBO> rewardArray;
private OnItemClickListener mItemClickListener;
public static final int VIEW_TYPE_PROGRESS = 0;
public static final int VIEW_TYPE_ITEM = 1;
public static final int VIEW_TYPE_HEADER = 2;
public RewardFinalAdapter(Context context, ArrayList<RewardItemBO> mainItems) {
this.context = context;
rewardArray = getFilterRewards(mainItems);
}
public void resetArray(ArrayList<RewardItemBO> latestArray)
{
rewardArray = getFilterRewards(latestArray);
}
public void setArrayItems(ArrayList<RewardItemBO> latestArray) {
rewardArray = latestArray;
}
#Override
public int getItemViewType(int position) {
if(rewardArray.get(position).isHeader())
return VIEW_TYPE_HEADER;
else if(rewardArray.get(position).isShowProgress())
return VIEW_TYPE_PROGRESS;
else
return VIEW_TYPE_ITEM;
}
#Override
public int getItemCount() {
return rewardArray.size();
}
public RewardItemBO getItem(int position) {
return rewardArray.get(position);
}
public void addItems( ArrayList<RewardItemBO> overallItem){
rewardArray = getFilterRewards(overallItem);
// notifyItemInserted(items.size() - 1);
this.notifyDataSetChanged();
}
// Create new views (invoked by the layout manager)
#Override
public MainViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
switch (viewType){
case VIEW_TYPE_HEADER:
View itemView = LayoutInflater.from(viewGroup.getContext())
.inflate(R.layout.order_list_header, viewGroup, false);
return new RewardListViewHolderHeader(itemView);
case VIEW_TYPE_ITEM:
View view = LayoutInflater.from(context).inflate(R.layout.item_rewards, viewGroup, false);
return new RewardViewHolder(view);
case VIEW_TYPE_PROGRESS:
Log.v("view_type_progress","I am in VIEW_TYPE_PROGRESS");
View progressView = LayoutInflater.from(context).inflate(R.layout.progress_loader, viewGroup, false);
return new ProgressViewHolder(progressView);
}
return null;
}
// Replace the contents of a view (invoked by the layout manager)
#Override
public void onBindViewHolder(MainViewHolder viewHolder, int position) {
RewardItemBO rewardItemBO= rewardArray.get(position);
if(viewHolder instanceof RewardViewHolder)
{
RewardViewHolder rewardViewHolder=(RewardViewHolder) viewHolder;
rewardViewHolder.tvRewardTitle.setText(rewardArray.get(position).getRewardTitle());
rewardViewHolder.tvRewardDescription.setText(rewardArray.get(position).getRewardMessage());
String formatedDate = DateTimeOp.oneFormatToAnother(rewardArray.get(position).getRewardExpiryDate(), Constants.dateFormat18, Constants.dateFormat6);
rewardViewHolder.tvRewardExpiry.setText("Expires " + formatedDate);
if(rewardArray.get(position).getRewardShowRedeem().equals("1"))
{
rewardViewHolder.btnGrey.setVisibility(View.VISIBLE);
rewardViewHolder.btnGrey.setText("Redeemed");
}
else if(rewardArray.get(position).getRewardExpired().equals("1"))
{
rewardViewHolder.btnGrey.setVisibility(View.VISIBLE);
rewardViewHolder.btnGrey.setText("Expired");
}
else
{
rewardViewHolder.btnOrange.setVisibility(View.VISIBLE);
rewardViewHolder.btnOrange.setText("Get Code");
}
}
else if(viewHolder instanceof RewardListViewHolderHeader)
{
RewardListViewHolderHeader holder = (RewardListViewHolderHeader ) viewHolder;
holder.tvHeader.setText(rewardItemBO.getHeaderTitle());
}
else if(viewHolder instanceof ProgressViewHolder)
{
ProgressViewHolder progressViewHolder = (ProgressViewHolder) viewHolder;
progressViewHolder.progressBar.setIndeterminate(true);
}
}
public void addOnTop(ArrayList<RewardItemBO> topItemList) {
Collections.reverse(topItemList);
rewardArray.addAll(0, topItemList);
notifyItemRangeInserted(0, topItemList.size());
}
public interface OnItemClickListener {
public void onItemClick(View view , int position);
}
public void SetOnItemClickListener(final OnItemClickListener mItemClickListener) {
this.mItemClickListener = mItemClickListener;
}
#Override
public long getItemId(int position) {
return position;
}
public ArrayList<RewardItemBO> getFilterRewards(ArrayList<RewardItemBO> mainItems){
ArrayList<RewardItemBO> currentRewardList = new ArrayList<RewardItemBO>();
ArrayList<RewardItemBO> pastRewardList = new ArrayList<RewardItemBO>();
ArrayList<RewardItemBO> dummyArray = new ArrayList<>();
for (RewardItemBO rewardItemBO : mainItems) {
try {
//because reward item with progress have everything null in it.
if(rewardItemBO.getRewardExpired()!=null && !rewardItemBO.isShowProgress())
{
int isExpired = Integer.parseInt(rewardItemBO.getRewardExpired());
if(isExpired==1)
pastRewardList.add(rewardItemBO);
else
currentRewardList.add(rewardItemBO);
}
}catch (NumberFormatException e){
e.printStackTrace();
}
}
if(currentRewardList.size()>0){
currentRewardList.add(0, new RewardItemBO(context.getResources().getString(R.string.Current)));
dummyArray.addAll(currentRewardList);
}
if(pastRewardList.size()>0){
pastRewardList.add(0, new RewardItemBO(context.getResources().getString(R.string.Past)));
dummyArray.addAll(pastRewardList);
}
return dummyArray;
}
public void addProgressView()
{
rewardArray.add(new RewardItemBO(true));
//notifyItemChanged(rewardArray.size());
notifyDataSetChanged();
}
public void removeProgressView(){
int position = rewardArray.size() -1;
rewardArray.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, rewardArray.size());
}
public static class RewardListViewHolderHeader extends MainViewHolder {
protected TextView tvHeader;
public RewardListViewHolderHeader (View v) {
super(v);
tvHeader = (TextView) v.findViewById(R.id.header_text);
}
}
public class RewardViewHolder extends MainViewHolder implements View.OnClickListener{
public TextView tvRewardTitle;
public TextView tvRewardDescription;
public TextView tvRewardExpiry;
public Button btnOrange,btnGrey;
public RewardViewHolder(View v) {
super(v);
tvRewardTitle = (TextView) itemView.findViewById(R.id.tv_reward_title);
tvRewardDescription = (TextView) itemView.findViewById(R.id.tv_reward_description);
tvRewardExpiry = (TextView) itemView.findViewById(R.id.tv_reward_expiry_date);
btnOrange = (Button) itemView.findViewById(R.id.btn_item_reward_orange);
btnGrey = (Button) itemView.findViewById(R.id.btn_item_reward_grey);
btnOrange.setOnClickListener(this);
btnGrey.setOnClickListener(this);
}
#Override
public void onClick(View v) {
//Toast.makeText(context, tvName.getText().toString(), Toast.LENGTH_SHORT).show();
if (mItemClickListener != null) {
mItemClickListener.onItemClick(v,getAdapterPosition());
}
}
}
}