Android recyclerview not setting the items on first attempt - android

In my activity, I have a recyclerview which displays the images in grid. The activity shows images from a collection.When the collection already contains images and I open the activity, the recyclerview sets all the images properly. My problem is when the I select image from gallery or camera and in onActivityResult() method try to set that to recyclerview using adapter.notifyDataSetChanged() method, the recyclerview is not getting updated if the collection is empty. And the same code is working fine if the collection contains images and I try to upload new image to it. Basically, I'm selecting images from gallery and then in onActivityResult() method I'm setting the selected images to the recyclerview and the images are uploaded in the background to the server.
My Adapter code
private void setAdapter(final List<AlbumImagesBean> albumImages) {
adapter = new MyRecyclerAdapter<AlbumImagesBean>(R.layout.album_images_grid_adapter_item) {
#Override
protected void setupViewHolder(MAWRecyclerViewHolder holder, final int position, final AlbumImagesBean item) {
mawViewHolder = holder;
ProgressBar progressBar = holder.getView(R.id.progressBar);
((ImageView) holder.getView(R.id.ivImage)).setImageURI(Uri.parse(item.getImage()));
}
};
adapter.init(albumImages, false);
recyclerView.setLayoutManager(new GridLayoutManager(this, 3));
recyclerView.addItemDecoration(new GridRecyclerViewDivider(5, 3));
recyclerView.setAdapter(adapter);
}
onActivityResult() method code
ArrayList<String> images = data.getStringArrayListExtra(UIConstants.INTENT_EXTRA_IMAGES);
if (isNotNull(images)) {
for (int i = 0; i < images.size(); i++) {
String path = images.get(i);
newRequests = new ArrayList<>();
AddFileRequest request = new AddFileRequest();
request.setUserId(userCache.getUserData().getUserId());
request.setType(UIConstants.UPLOAD_FILE_TYPE_ALBUM);
request.setTypeId(albumBean.getAlbumId());
request.setTitle(EMPTY);
request.setFile(path);
AlbumImagesBean imageBean = new AlbumImagesBean(path);
imageBean.setUploading(true);
imageBean.setLocalImage(true);
adapter.addItem(imageBean);
albumImages = adapter.getData();
newRequests.add(request);
uploadAttachmentAPICall();
}
adapter.notifyDataSetChanged();
}
I'm not able to understand what's going wrong.Thanks for any help.
public void addItem(T t) {
createDataIfNotExits();
data.add(t);
notifyChanges();
}
public List<T> getData() {
return data;
}
private void createDataIfNotExits() {
if (data == null) {
data = new ArrayList<>();
}
}
public void init(List<T> data, boolean isPagination) {
MAWRecyclerAdapter.isPagination = isPagination;
if (data == null) {
throw new NullPointerException("data can not be null");
}
this.data = data;
if (isPagination) {
this.data.add(null);
}
notifyChanges();
}
Also I have called adapter.notifyDataSetChanged( ); in the response of API call , but still the image is not added to recyclerview.

Related

Why my recyclerView doesn't display the new data after the adapter notify data is changed?

In the parent activity, I have an edit text in a toolbar, and user can make a search through the data displayed by the recyclerview.
When the user push enter key down, the string in the edittext is sent to the fragment by :
Bundle bundle = new Bundle();
bundle.putString(predResult, placeid);
MapFragment mapFragment = new MapFragment();
ListRestFragment listRestFragment = new ListRestFragment();
mapFragment.setArguments(bundle);
listRestFragment.setArguments(bundle);
getSupportFragmentManager().beginTransaction()
.replace(R.id.map, mapFragment)
.replace(R.id.list_frag, listRestFragment)
.commit();
but, unfortunatly, the recyclerview is not resfreshed while my adapter is notified the data is changed as it shown below:
private void queryToList(Query query) {
query.addSnapshotListener((queryDocumentSnapshots, e) -> {
restaurantList = queryDocumentSnapshots.toObjects(Restaurant.class);
if (!myPrediction.contains("myPrediction")) {
System.out.println(myPrediction);
for (Restaurant item : restaurantList) {
if (item.getRestaurantID().contains(myPrediction)) {
restaurantListPred = new ArrayList<>();
restaurantListPred.add(item);
updateUI(restaurantListPred);
}
}
} else updateUI(restaurantList);
});
}
private void updateUI(List<Restaurant> restaurants) {
configureFab();
configureRecyclerView(restaurants);
}
private void configureRecyclerView(List<Restaurant> restaurant) {
this.adapter = new RestaurantAdapterClassic(restaurant);
this.recyclerView.setAdapter(this.adapter);
this.recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(), DividerItemDecoration.VERTICAL);
recyclerView.addItemDecoration(new SimpleItemDecorator(getContext()));
}
the new List is updated automatically when the user makes his request, but the recyclerView doesn't display the new data.
if you want to check my adapter implementation:
public class RestaurantAdapterClassic extends RecyclerView.Adapter<RestaurantViewHolder> {
private List<Restaurant> restaurantsList;
// CONSTRUCTOR
public RestaurantAdapterClassic(List<Restaurant> restaurants) {
this.restaurantsList = restaurants;
}
#Override
public RestaurantViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
// CREATE VIEW HOLDER AND INFLATING ITS XML LAYOUT
Context context = parent.getContext();
LayoutInflater inflater = LayoutInflater.from(context);
View view = inflater.inflate(R.layout.listview_pattern, parent, false);
return new RestaurantViewHolder(view);
}
#Override
public void onBindViewHolder(RestaurantViewHolder viewHolder, int position) {
viewHolder.updateWithRestaurant(this.restaurantsList.get(position));
}
// RETURN THE TOTAL COUNT OF ITEMS IN THE LIST
#Override
public int getItemCount() {
return this.restaurantsList.size();
}
public Restaurant getRestaurant(int position) {
return this.restaurantsList.get(position);
}
public void filterList(List<Restaurant> filteredList) {
restaurantsList = filteredList;
notifyDataSetChanged();
}
}
where is my error or my misunderstanding?
EDIT SOLUTION -
Create an Interface
Actually, to send the new data data from my Parent Activity to my Fragment with a listener to observe when the data changes.
Keep The data reference sent to the adapter
Actually, the main big problem that I had was my adapter doesn't refresh when I sent new array. The reason was an adapter creates a reference with the list/array. if you want to refresh it, you need to keep this reference by get the list, erase it, and put/add new data inside by the method addALL for example.
First of all, adapter.notifyDataSetChanged(); doesn't have any effect in the code as inside updateUI you create the adapter every time you call it.
I think, the main problem is in here:
if (item.getRestaurantID().contains(myPrediction)) {
restaurantListPred = new ArrayList<>();
restaurantListPred.add(item);
updateUI(restaurantListPred);
}
This block doesn’t execute at all. Thats why the list not updated.

RecyclerView Not Showing Data Passed From List Through Bundle

I have a recyclerview in a dialog fragment, which hosts a tab layout, containing a list of checkable items and a button each. When an item is selected, it is passed on click through the bundle to this parent dialog fragment like this:
doneBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
retrieveSessions();
}
});
private void retrieveSessions() {
NewProgramDialog dialog = new NewProgramDialog(); // parent dialog fragment is passed the list items here
Bundle bundle = new Bundle();
String s = new Gson().toJson(myItemsList);
bundle.putString(KEY_MY_SESSIONS, s);
bundle.putBoolean("from_selections", true);
dialog.setArguments(bundle);
dialog.show(getChildFragmentManager(), "NewProgramDialog");
dismiss();
}
The data for recyclerview is received through a bundle lie shown above and the list items are retrieved using Gson and converted to type String, a query is run on the database to get the session model class info.
These sessions are added to the adapter arraylist like below:
private void populateSessions() {
addProgramSessionsRV.setHasFixedSize(true);
addProgramSessionsRV.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.HORIZONTAL, false));
// TODO: 2/05/2019 show the added sessions here
Bundle bundle = getArguments();
if (bundle != null) {
String s = bundle.getString(KEY_MY_SESSIONS); / getting the items from bundle
myItemsList = new Gson().fromJson(s, ArrayList.class); // parsing to List<String> type
Log.d(TAG, "Items size:\t" + myItemsList.size()); //works
}
adapter = new AddProgramSessionsAdapter(getActivity(), sessionsList);
addProgramSessionsRV.setAdapter(adapter);
Log.d(TAG, "Items in adapter:\t" + adapter.getItemCount()); // shows total items received from bundle
for (String s : myItemsList){
Log.d(TAG, "Ids:\t" + s);
Sessions session = SQLite.select()
.from(Sessions.class)
.where(Sessions_Table.prog_sessionId.eq(s))
.querySingle();
sessionsList.add(session);
Log.d(TAG, "Session List Size:\t" + sessionsList.size());
adapter = new AddProgramSessionsAdapter(getActivity(), sessionsList);
addProgramSessionsRV.setAdapter(adapter);
Log.d(TAG, "Items in adapter:\t" + adapter.getItemCount());
}
}
Still the ui shows no items from this method. I have added the data manually using this snippet and it shows Session 1 item in view but not the data from db in for loop.
Test Case:
Sessions sessions = new Sessions();
sessions.setSession_name("Test one");
sessions.setProgram_id("234");
sessions.setProg_sessionId("91");
sessionsList.add(sessions);
adapter = new AddProgramSessionsAdapter(getActivity(), sessionsList);
addProgramSessionsRV.setAdapter(adapter);
Log.d(TAG, "Items in adapter:\t" + adapter.getItemCount());
Is there any reason why setting the adapter to a list which has items does not work in the for loop db query (works)? Please explain to me why the ui shows nothing. Thanks.
Here's the adapter code:
public class AddProgramSessionsAdapter extends RecyclerView.Adapter<AddProgramSessionViewHolder> {
private final Context context;
private List<Sessions> itemsList;
public AddProgramSessionsAdapter(Context context, List<Sessions> itemsList) {
this.context = context;
this.itemsList = itemsList;
}
#Override
public AddProgramSessionViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.add_program_sessions_items_layout, parent, false);
return new AddProgramSessionViewHolder(view);
}
#Override
public void onBindViewHolder(AddProgramSessionViewHolder viewholder, int position) {
Sessions sessions = itemsList.get(position);
viewholder.add_program_sessionNameTV.setText(sessions.session_name);
Picasso.with(context)
.load(R.drawable.app_logo_resized)
.into(viewholder.add_program_sessionIV);
}
#Override
public int getItemCount() {
if (itemsList == null) {
return 0;
}
return itemsList.size();
}
}

add elements to top RealmRecyclerViewAdapter

I developing news feed like twitter, facebook and etc.
I have a server that gives me portions of articles for 10 pieces.
When I scroll down, new articles are loaded, added to the database and displayed in RealmRecyclerView.
I added SwipeRefreshLayout to update the data (in the case when new quotes came in).
I have a problem with adding new items to the top when i use SwipeRefreshLayout.
My idea was to sort new articles on id. In that case, when I scroll down the items with the smaller ones the id will be at the bottom, and when I use SwipeRefreshLayout new articles with higher id are download and adding in top list.
MyFragment
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_view_all_quotes, container, false);
swipeRefreshLayout = (SwipeRefreshLayout) view.findViewById(R.id.swipe_refresh_layout);
swipeRefreshLayout.setOnRefreshListener(this);
Realm.init(getActivity());
realm = Realm.getDefaultInstance();
recyclerView = (RecyclerView) view.findViewById(R.id.recyclerView);
recyclerView.setHasFixedSize(true);
LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(layoutManager);
adapter = new QuoteAdapter(realm.where(QuoteObject.class).findAllSortedAsync("id", Sort.DESCENDING), getActivity());
recyclerView.setAdapter(adapter);
return view;
}
#Override
public void onRefresh() {
int position = realm.where(QuoteObject.class).findAll().size();
DownloadDataFromServer.DownloadQuotes downloadQuotes =
new DownloadDataFromServer.DownloadQuotes();
try {
DownloadDataFromServer.DownloadQuotes.FlagQuotes = true;
downloadQuotes.execute(position+1).get();
}catch (Exception e){
Log.e(TAG, "Error", e);
}finally {
swipeRefreshLayout.setRefreshing(false);
}
}
RealmRecyclerViewAdapter
class QuoteAdapter extends RealmRecyclerViewAdapter<QuoteObject, QuoteAdapter.AllQuotesViewHolder> {
QuoteAdapter(OrderedRealmCollection<QuoteObject> quotes, Context context) {
super(quotes, true);
this.context = context;
if (quotes.size() == 0) downloadData(0);
}
.
.
.
#Override
public void onBindViewHolder(final QuoteAdapter.AllQuotesViewHolder viewHolder, int position) {
if (position == getData().size() - 1) downloadData(position);
....
}
But it does not work, the new data is loaded but does not add to top
Since I'm doing this for the first time, maybe I did not choose the right approach.
If you did this, tell how to create a news feed correctly.
If you don't have a updated field by which you can do
findAllSortedAsync("updated", Sort.DESCENDING)
Then you might want to consider adding a RANK field, and sort based on that.
For example,
// when downloading new items by "SwipeToRefresh" from top
// inside Realm transaction
RealmResults<FeedItem> feedItems = dao.findAll(realm);
for(int i = feedItems.size() - 1; i >= 0; i--) {
FeedItem feedItem = feedItems.get(i);
feedItem.setRank(feedItem.getRank() + response.size());
}
long rank = 1;
FeedItem defaultInstance = new FeedItem();
for(FeedItemDTO dto : response) {
FeedItem realmObject = mapper.toRealmObject(realm, dto, defaultInstance);
realmObject.setRank(rank++);
dao.insertOrUpdate(realm, realmObject);
}
And
// when download new items by scrolling to bottom
// inside Realm transaction
long count = dao.count(realm);
long rank = count + 1;
FeedItem defaultInstance = new FeedItem();
for(FeedItemDTO dto : response) {
FeedItem realmObject = mapper.toRealmObject(realm, dto, defaultInstance);
realmObject.setRank(rank++);
dao.insertOrUpdate(realm, realmObject);
}
public FeedItem toRealmObject(Realm realm, FeedItemDTO dto, FeedItemInterface defaultInstance) {
if(defaultInstance == null) {
defaultInstance = new FeedItem();
}
defaultInstance.setId(dto.getId());
RealmList<FeedCategory> categoryIds = new RealmList<FeedCategory>();
if(dto.getCategoryIds() != null) {
for(Long categoryId : dto.getCategoryIds()) {
FeedCategory feedCategory = feedCategoryRepository.findOne(realm, categoryId);
if(feedCategory != null) {
categoryIds.add(feedCategory);
}
}
}
defaultInstance.setCategoryIds(categoryIds);
defaultInstance.setCreatedTime(new Date(dto.getCreatedTime()));
defaultInstance.setUpdatedTime(new Date(dto.getUpdatedTime()));
defaultInstance.setTitle(dto.getTitle());
defaultInstance.setShortDescription(dto.getShortDescription());
defaultInstance.setNumberOfLikes(dto.getNumberOfLikes());
defaultInstance.setIsLiked(dto.getIsLiked());
defaultInstance.setIsFavorited(dto.getIsFavorited());
defaultInstance.setIsImportant(dto.getIsImportant());
defaultInstance.setImageUrl(dto.getImageUrl());
defaultInstance.setTypeCode(dto.getTypeCode());
defaultInstance.setResultTypeCode(dto.getResultTypeCode());
return defaultInstance;
}

Wrong item in recyclerview after filtering

hi i have a RecyclerView adapter as follow :-
public class RecyclerViewAdapter extends RecyclerView.Adapter<ViewHolder> {
List<Data> list = Collections.emptyList();
Context context;
public RecyclerViewAdapter(List<Data> list, Context context) {
this.list = list;
this.context = context;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
//Inflate the layout, initialize the View Holder
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.apps_layout, parent, false);
ViewHolder holder = new ViewHolder(v);
return holder;
}
#Override
public void onViewDetachedFromWindow(ViewHolder holder) {
super.onViewDetachedFromWindow(holder);
((ViewHolder)holder).itemView.clearAnimation();
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
//Use the provided View Holder on the onCreateViewHolder method to populate the current row on the RecyclerView
holder.title.setText(list.get(position).title);
holder.description.setText(list.get(position).description);
}
public void setFilter(List<Data> searched_data) {
list = new ArrayList<>();
list.addAll(searched_data);
notifyDataSetChanged();
}
#Override
public int getItemCount() {
//returns the number of elements the RecyclerView will display
return list.size();
}
#Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
}
// Insert a new item to the RecyclerView on a predefined position
public void insert(int position, Data data) {
list.add(position, data);
notifyItemInserted(position);
}
// Remove a RecyclerView item containing a specified Data object
public void remove(Data data) {
int position = list.indexOf(data);
list.remove(position);
notifyItemRemoved(position);
}
}
okay now as you can see setFilter method to filter recyclerview list
here is how i call it
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String s) {
return false;
}
#Override
public boolean onQueryTextChange(String s) {
List<Data> filteredModelList = filter(data, s);
adapter.setFilter(filteredModelList);
return true;
}
});
now filter works fine now when i click on it the position is wrong
i know the error coming from the position as the older recyclerview on click has old position index i dont know how to fix it anyway here is onclicklistener
data = appsdata(); // load the list List<Data>
Collections.sort(data); // sorting
recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
final LinearLayoutManager layoutManager = new LinearLayoutManager(this);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView.setLayoutManager(layoutManager);
adapter = new RecyclerViewAdapter(data, this);
recyclerView.setAdapter(adapter);
recyclerView.setNestedScrollingEnabled(false);
recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(this, recyclerView, new RecyclerItemClickListener.OnItemClickListener() {
#Override
public void onItemClick(View view, int position) {
String s = data.get(position).title;
String ss = data.get(position).description;
Intent intent = new Intent(MainAcitivity.this, Work.class);
intent.putExtra("title", s);
intent.putExtra("desc", ss);
startActivity(intent);
}
}));
i know this line is causing problem
String s = data.get(position).title;
because it is same as old when list was not filtered ,how i can update this recyclerview so that i can get updated index when launching Work.class
okay guys this what works partially for me
i tried updating the data list by adding
data = filteredModelList; // add this line
after filtering and this worked fine
#Override
public boolean onQueryTextChange(String s) {
List<Data> filteredModelList = filter(data, s);
adapter.setFilter(filteredModelList);
data = filteredModelList; // add this line
return true;
}
now i get real index but when i search and clear the list the list is empty because i replaced the data list :(
EDIT :- i fixed it by hack not a nice way but works
as you can see the old list was gone by using above stuff before edit
when i used to change the data list
data = filteredModelList; // add this line
then the new data list has only filtered values and when you clear searchView then that data list is empty because it does not have those all apps list what i did was that i made new list as data_fix and onclicklistener i used datafix instead of data list
see this how
RecyclerItemClickListener method
String s = datafix.get(position).title; // data.get to datafix.get
String ss = datafix.get(position).description; // data.get to datafix.get
now onsetfilter call
i called this
datafix = filteredModelList; // instead of data = filteredModelList;
also i initialize it oncreate so it is not empty on launch of the app by
data = appsdata(); // load the list List<Data>
datafix = appsdata(); // load the list List<Data> added just below it to intialize
now this way the full loaded applist // List data stays full and doesnot clear even if you clear from searchView and index is all right
The logic lies to how you update the recycler view items,
public void setFilter(List<Data> searched_data) {
list = new ArrayList<>();
list.addAll(searched_data);
notifyDataSetChanged();
}
The above line is not necessary, adapter = new RecyclerViewAdapter(data, this); this line is very important to understand. You see when you pass data to the adapter is like this you are creating a symbolic link between the list in the adapter and outside. So therefore any changes made to the outside list, to update the adapter version.Just call adapter.notifyDatasetChange method
do this whenever any changes are made to the data model object.
CHANGE THE FOLLOWING FROM
List<Data> filteredModelList = filter(data, s);
adapter.setFilter(filteredModelList);
data = filteredModelList; // add this line
return true;
TO,
adapter.list.clear();
data = filter(data, s);
adapter.notifyDataSetChange();

recyclerview add data to the top without mess up scroll?

I'm trying to add some date on scroll top in a recyclerview.
it is work, except the scroll, it mess everything up when some new data is added.
I saw this topics:
Link 1
Link 2
but none of them solved my problem.
maybe someone can help me with this...
I get some data using volley, like so:
try {
//Getting json
json = array.getJSONObject(i);
//Adding data to the object
PostObj.setImageUrl(json.getString(Config.TAG_PPIC));
...
} catch (JSONException e) {
e.printStackTrace();
}
//Adding object to the list
listLf.add(0, PostObj); //0, postobj
}
//Notifying the adapter that data has been added or changed
//adapter.notifyDataSetChanged(); the scroll will jump to position 0
adapter.notifyItemRangeChanged(0, adapter.getItemCount()); // still not working
}
I tried to add adapter.notifyItemRangeChanged(0, adapter.getItemCount()); but still the same thing.
also I tried:
// Save state
private Parcelable recyclerViewState;
recyclerViewState = recyclerView.getLayoutManager().onSaveInstanceState();
// Restore state
recyclerView.getLayoutManager().onRestoreInstanceState(recyclerViewState);
and it doesn't work too. maybe I place it in the wrong place or something...
I want some suggestions what I'm doing wrong and how can I get the new data, notify the adapter without mess the scroll position?
edit----------------------------------
full class:
public class Comments extends BaseActivity {
private List<LfGetSet> listLf;
//Creating Views
private RecyclerView recyclerView;
private RecyclerView.LayoutManager layoutManager;
private RecyclerView.Adapter adapter;
//Volley Request Queue
private RequestQueue requestQueue;
private String requestCount = "0";
private String lastrequestCount = "0";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ViewGroup content = (ViewGroup) findViewById(R.id.content_frame);
getLayoutInflater().inflate(R.layout.activity_comments, content, true);
//Initializing Views
recyclerView = (RecyclerView) findViewById(R.id.recyclerViewLf);
recyclerView.setHasFixedSize(true);
//layoutManager = new LinearLayoutManager(this);
final LinearLayoutManager layoutManager = new LinearLayoutManager(this);
layoutManager.setStackFromEnd(true);
recyclerView.setLayoutManager(layoutManager);
//Initializing our list
listLf = new ArrayList<>();
requestQueue = Volley.newRequestQueue(this);
//Calling method to get data to fetch data
getData();
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
if (isLastItemDisplaying(recyclerView)) {
getData();
}
}
});
//initializing our adapter
adapter = new LfAdapter(listLf, this);
//Adding adapter to recyclerview
recyclerView.setAdapter(adapter);
}
private JsonArrayRequest getDataFromServer(String requestCount) {
...
return jsonArrayRequest;
}
//This method will get data from the web api
private void getData() {
//Adding the method to the queue by calling the method getDataFromServer
requestQueue.add(getDataFromServer(requestCount));
lastrequestCount = requestCount;
//Incrementing the request counter
requestCount++;
}
//This method will parse json data
private void parseData(JSONArray array) {
for (int i = 0; i < array.length(); i++) {
//Creating the object
LfGetSet PostObj = new LfGetSet();
JSONObject json = null;
try {
//Getting json
json = array.getJSONObject(i);
//Adding data to the object
PostObj.setImageUrl(json.getString(Config.TAG_PPIC));
...
} catch (JSONException e) {
e.printStackTrace();
}
//Adding object to the list
listLf.add(0, PostObj); //0, postobj
}
//Notifying the adapter that data has been added or changed
adapter.notifyDataSetChanged();
}
//This method would check that the recyclerview scroll has reached the bottom or not
private boolean isLastItemDisplaying(RecyclerView recyclerView) {
if (recyclerView.getAdapter().getItemCount() != 0) {
int lastVisibleItemPosition = ((LinearLayoutManager) recyclerView.getLayoutManager()).findFirstVisibleItemPosition();
if (lastVisibleItemPosition != RecyclerView.NO_POSITION
&& lastVisibleItemPosition == 1
&& lastrequestCount != requestCount
&& requestCount != "0")
return true;
}
return false;
}
}
You can try this approach where you add a new item to the list as per normal and then update the data in the array and put the new one at the top.
// Add a new item the usual way so it goes at the bottom
int x = 0;
// Create a new Data list. New item goes 1st
// Create a Loop
myList.remove(x); // Remove item from the array at position
MyList myList = new MyList();
myList.add(x, theData); // Add data to array at position
// Now that new data has been inserted to the Array at position X update the List item at that same Position. I usually do this in the Background.
Handler handler = new Handler();
final int finalX = x;
final Runnable r = new Runnable() {
public void run() {
adapter.notifyItemChanged(finalX); // Notify Adapter that the Items data has changed and Update
}
};
handler.post(r);
x++;
Code that reads updated data from the DB and then updates List items on the fly with that new data. But in your case you need to add 1 new item and update the List with the new items data at position 0 in the array and on the List. Old items get their position shifted by 1.
public void updateStocks() {
System.out.println("Updating");
int rec = db.getRecordsCount() - 1;
List<Records> record = db.getAllRecords();
int x = 0;
for (Records cn : record) {
stocksList.remove(x);
Livestocks stocks = new Livestocks();
stocks.setID(cn.getID());
stocks.setName(cn.getName());
stocks.setTicker(cn.getTicker());
stocks.setPrice(cn.getPrice());
stocks.setOpen(cn.getOpen());
stocks.setChange(cn.getChange());
stocks.setPchange(cn.getPchange());
stocks.setDhigh(cn.getDhigh());
stocks.setDlow(cn.getDlow());
stocks.setYhigh(cn.getYhigh());
stocks.setYlow(cn.getYlow());
stocks.setVol(cn.getVol());
stocks.setShares(cn.getShares());
stocks.setIown(cn.getIown());
stocks.setMcap(cn.getMcap());
stocks.setStatus(cn.getStatus());
stocks.setExchange(cn.getExchange());
stocksList.add(x, stocks);
Handler handler = new Handler();
final int finalX = x;
final Runnable r = new Runnable() {
public void run() {
adapter.notifyItemChanged(finalX);
}
};
handler.post(r);
x++;
if (rec == x) {
//do nothing
}
}
}

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