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How to update listview in Fragment with custom adapter

I am giving product id with barcode scanner. I can add product to listView but when i try to increase or decrease amount of the product. It doesn't update UI. I used Toast message to see weather list is updated, it updates list but doesn't update UI
I have tried to use runOnUiThread() but i couldn't find any solution. How to update UI can you please help me
custom_lisView_row
BaseActivity which keeps MainFragment on it
public class BaseActivity extends AppCompatActivity {
public static final String MAIN_FRAGMENT = "mainFragment";
public static final String PRODUCTS = "products";
FragmentManager fragmentManager;
Dialog dialog ;
public static ArrayList<MyProduct> myProductList = new ArrayList<>();
public static MyTablet myTablet = new MyTablet();
Activity mActivity;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_base);
//Initialize fragment manager
fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.fl_BaseActivity, new MainFragment()).commit();
//Create database
mDatabase = FirebaseDatabase.getInstance().getReference();
dialog = new Dialog(this);
//Runs when i enter product id
initScanner();
}
public void updateMyProductList(MyProduct myProduct){
for(int i= 0 ; i< myProductList.size() ; i++ ){
MyProduct temp = myProductList.get(i);
if (temp.getId().equals(myProduct.getId())) {
temp.setAmount(temp.getAmount() + myProduct.getAmount());
myProductList.set(i, temp);
return;
}
}
myProductList.add(myProduct);
updateMainFragment();
}
private void initScanner() {
mDatabase.child(PRODUCTS).child(finalData).get().addOnCompleteListener(new OnCompleteListener<DataSnapshot>() {
#Override
public void onComplete(#NonNull Task<DataSnapshot> task) {
MyProduct myProduct = task.getResult().getValue(MyProduct.class);
myProduct.setAmount(1);
dialog.setContentView(R.layout.custom_product_dialog);
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
dialog.setCancelable(false);
TextView tv_addBasket_product_dialog = dialog.findViewById(R.id.tv_addBasket_product_dialog);
tv_addBasket_product_dialog.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
updateMyProductList(myProduct);
dialog.dismiss();
}
});
dialog.show();
}
};
}
public void updateMainFragment() {
if (isExist(MAIN_FRAGMENT)) {
Fragment fragment = findFragment(MAIN_FRAGMENT);
((MainFragment) fragment).updateMyList();
}
}
//Add fragments to BaseActivity
public void addFragments(Fragment fragment, String tag) {
fragmentManager.beginTransaction().add(R.id.fl_BaseActivity, fragment, tag).commit();
}
//Replace fragments to BaseActivity
public void replaceFragments(Fragment fragment, String tag) {
fragmentManager.beginTransaction().replace(R.id.fl_BaseActivity, fragment, tag).commit();
}
//Remove fragment from BaseActivity
public void removeFragment(String tag) {
Fragment fragmentB = fragmentManager.findFragmentByTag(tag);
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
if (fragmentB != null) {
fragmentTransaction.remove(fragmentB);
fragmentTransaction.commit();
}
}
// finds fragment and returns it
// It may return null first check fragment is exist. use isExist() method
public Fragment findFragment(String tag) {
Fragment fragment = fragmentManager.findFragmentByTag(tag);
return fragment;
}
//Check fragment exist in BaseActivity
public boolean isExist(String tag) {
Fragment fragmentB = fragmentManager.findFragmentByTag(tag);
if (fragmentB != null) {
return true;
}
return false;
}
}
MainFragment
public class MainFragment extends Fragment {
ListView lv_MainFragment;
public MyProductListAdapter myListAdapter;
public static ArrayList<MyProduct> myProductList;
Activity mActivity;
#Override
public void onAttach(Context context) {
super.onAttach(context);
mActivity = getActivity();
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
myProductList = BaseActivity.myProductList;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_main, container, false);
lv_MainFragment = view.findViewById(R.id.lv_MainFragment);
myListAdapter = new MyProductListAdapter(mActivity.getApplicationContext(), R.layout.custom_product_list_row, myProductList);
lv_MainFragment.setAdapter(myListAdapter);
return view;
}
public void updateMyList() {
myProductList = BaseActivity.myProductList;
myListAdapter.notifyDataSetChanged();
}
}
MyProductListAdapter
public class MyProductListAdapter extends ArrayAdapter<MyProduct> {
private Context mContext;
private ArrayList<MyProduct> list;
AppCompatButton acb_DecreaseAmount_productListRow, acb_IncreaseAmount_productListRow;
public MyProductListAdapter(Context context, int resource, ArrayList<MyProduct> objects) {
super(context, resource, objects);
this.mContext = context;
this.list = objects;
}
#Override
public View getView(int position, #Nullable View convertView, #NonNull ViewGroup parent) {
View view = convertView;
if (view == null) {
LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.custom_product_list_row, parent, false);
tv_ProductAmount_productListRow = view.findViewById(R.id.tv_ProductAmount_productListRow);
acb_DecreaseAmount_productListRow = view.findViewById(R.id.acb_DecreaseAmount_productListRow);
acb_IncreaseAmount_productListRow = view.findViewById(R.id.acb_IncreaseAmount_productListRow);
tv_ProductAmount_productListRow.setText(String.valueOf(list.get(position).getAmount()));
acb_IncreaseAmount_productListRow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
double productPrice = list.get(position).getPrice();
int productAmount = list.get(position).getAmount();
productAmount++;
list.get(position).setAmount(productAmount);
Toast.makeText(mContext, String.valueOf(productAmount), Toast.LENGTH_SHORT).show();
tv_ProductAmount_productListRow.setText(String.valueOf(list.get(position).getAmount()));
}
});
acb_DecreaseAmount_productListRow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
int productAmount = list.get(position).getAmount();
if (productAmount > 1) {
double productPrice = list.get(position).getPrice();
productAmount--;
list.get(position).setAmount(productAmount);
Toast.makeText(mContext, String.valueOf(productAmount), Toast.LENGTH_SHORT).show();
tv_ProductAmount_productListRow.setText(String.valueOf(list.get(position).getAmount()));
}
}
});
}
return view;
}
}

Hej Metehan,
your use case sounds perfect for a RecyclerView with a ListAdapter. You just submit a new list of products to the adapter and it will handle the updating and notifying for you.

Passing events from DialogFragment back to RecyclerView Adapter

My fragment has a Recycler View. Therefore I have a RecyclerView Adapter too. From this Adapter, I am opening an AlertDialog. When I click OK, I need to pass the onclick event from my DialogFragment back to my RecyclerView Adapter.
Currently, I am doing it like here, but this passes the event back to the activity and not to the RecyclerView Adapter.
public class FreshwaterRecyclerViewAdapter extends RecyclerView.Adapter<FreshwaterRecyclerViewAdapter.ViewHolder> implements BiotopeDialogFragment.NoticeDialogListener {
private List<Biotope> data;
private LayoutInflater layoutInflater;
FreshwaterRecyclerViewAdapter(Context context, List<Biotope> data) {
this.layoutInflater = LayoutInflater.from(context);
this.data = data;
}
//The dialog fragment receives a reference to this Activity through the
//Fragment.onAttach() callback, which it uses to call the following methods
//defined by the NoticeDialogFragment.NoticeDialogListener interface
#Override
public void onDialogPositiveClick(DialogFragment dialog) {
notifyItemInserted(getItemCount()-1);
}
#Override
public void onDialogNegativeClick(DialogFragment dialog) {
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView;
if (viewType == R.layout.biotope_cardview){
itemView = layoutInflater.inflate(R.layout.biotope_cardview, parent, false);
} else {
itemView = layoutInflater.inflate(R.layout.biotope_add_button, parent, false);
}
return new ViewHolder(itemView);
}
#Override
public void onBindViewHolder(#NonNull ViewHolder holder, int position) {
if (position == data.size()) {
holder.imageButtonAddBiotope.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
FragmentManager fragmentManager = ((AppCompatActivity) layoutInflater.getContext()).getSupportFragmentManager();
DialogFragment dialog = new BiotopeDialogFragment();
dialog.show(fragmentManager, "NoticeDialogFragment");
}
});
} else {
holder.textViewBiotopeTitle.setText(getItem(position).name);
Picasso.get().load(Uri.parse(getItem(position).imageUri)).into(holder.imageViewBiotope);
LastValuesRecyclerViewAdapter recyclerAdapter = new LastValuesRecyclerViewAdapter(layoutInflater.getContext(), getData());
holder.recyclerViewLastValues.setLayoutManager(new LinearLayoutManager(layoutInflater.getContext(), LinearLayoutManager.HORIZONTAL, false));
holder.recyclerViewLastValues.setAdapter(recyclerAdapter);
}
}
//total number of rows
#Override
public int getItemCount() {
return data.size() + 1; //+1 for the add button
}
#Override
public int getItemViewType(int position) {
return (position == data.size()) ? R.layout.biotope_add_button : R.layout.biotope_cardview;
}
public static class ViewHolder extends RecyclerView.ViewHolder {
private TextView textViewBiotopeTitle;
private ImageView imageViewBiotope;
private RecyclerView recyclerViewLastValues;
private ImageButton imageButtonAddBiotope;
public ViewHolder(View view) {
super(view);
textViewBiotopeTitle = (TextView) view.findViewById(R.id.textViewBiotopeTitle);
imageViewBiotope = (ImageView) view.findViewById(R.id.imageViewBiotopeCardview);
recyclerViewLastValues = (RecyclerView) view.findViewById(R.id.recyclerViewLastValues);
imageButtonAddBiotope = (ImageButton) view.findViewById(R.id.imageButtonAddBiotope);
}
}
Biotope getItem(int id) {
return data.get(id);
}
private List<String> getData() {
List<String> data = new ArrayList<>();
data.add("PO4");
data.add("NO3");
return data;
}
}
This is my dialog.
public class BiotopeDialogFragment extends DialogFragment {
private NoticeDialogListener listener;
public interface NoticeDialogListener {
public void onDialogPositiveClick(DialogFragment dialog);
public void onDialogNegativeClick(DialogFragment dialog);
}
//Override the Fragment.onAttach() method to instantiate the NoticeDialogListener
#Override
public void onAttach(#NonNull Context context) {
super.onAttach(context);
//Verify that the host activity implements the callback interface
try {
//Instantiate the NoticeDialogListener so we can send events to the host
listener = (NoticeDialogListener) context;
} catch (ClassCastException e) {
//The activity doesn't implement the interface, throw exception
throw new ClassCastException("FreshwaterRecyclerViewAdapter must implement NoticeDialogListener | Context: " + context.toString());
}
}
public static final String TAG = "biotope_dialog_fragment";
private ActivityResultLauncher<Intent> activityResultLauncher;
private Uri imageUri = null;
#NonNull
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
MaterialAlertDialogBuilder builder = new MaterialAlertDialogBuilder(getContext());
LayoutInflater inflater = requireActivity().getLayoutInflater();
//Inflate and set the layout for the dialog
//Pass null as the parent view because its going in the dialog layout
View view = inflater.inflate(R.layout.fragment_dialog_biotope, null, false);
builder.setView(view);
View colorPickerPreviewView = view.findViewById(R.id.colorPickerPreviewView);
ColorPickerView colorPickerView = view.findViewById(R.id.colorPickerView);
ImageView imageViewBiotope = view.findViewById(R.id.imageViewBiotopePreview);
TextInputEditText textFieldBiotopeName = view.findViewById(R.id.textFieldBiotopeName);
builder.setTitle("New biotope")
.setPositiveButton("ok", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int id) {
BiotopeDatabase database = BiotopeDatabase.getDbInstance(requireContext().getApplicationContext());
Biotope biotope = new Biotope();
if (textFieldBiotopeName.getText() != null) {
biotope.name = textFieldBiotopeName.getText().toString();
} else {
biotope.name = "";
}
if (imageUri != null) {
biotope.imageUri = imageUri.toString();
} else {
biotope.imageUri = "";
}
biotope.color = colorPickerView.getColor();
database.biotopeDao().insertAll(biotope);
//Send the positive button event back to the host activity
listener.onDialogPositiveClick(BiotopeDialogFragment.this);
}
})
.setNegativeButton("noke", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
//Send the negative button event back to the host activity
listener.onDialogNegativeClick(BiotopeDialogFragment.this);
Objects.requireNonNull(BiotopeDialogFragment.this.getDialog()).cancel();
}
});
return builder.create();
}
public static BiotopeDialogFragment display(FragmentManager fragmentManager) {
BiotopeDialogFragment fragment = new BiotopeDialogFragment();
fragment.show(fragmentManager, TAG);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public void onViewCreated(#NonNull View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}
This is my fragment building the RecyclerView. Alternatively, I can pass the event back to the fragment if it is not possible to pass it to the adapter.
public class BiotopesFragment extends Fragment {
private FreshwaterRecyclerViewAdapter recyclerAdapter;
public static BiotopesFragment newInstance(String param1, String param2) {
BiotopesFragment fragment = new BiotopesFragment();
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_biotopes, container, false);
RecyclerView recyclerViewFreshwater = (RecyclerView) root.findViewById(R.id.recyclerViewFreshwater);
recyclerAdapter = new FreshwaterRecyclerViewAdapter(getContext(), getData());
recyclerViewFreshwater.setLayoutManager(new LinearLayoutManager(getContext(), LinearLayoutManager.HORIZONTAL, false));
recyclerViewFreshwater.setAdapter(recyclerAdapter);
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(getContext(), DividerItemDecoration.VERTICAL);
recyclerViewFreshwater.addItemDecoration(dividerItemDecoration);
ItemTouchHelper itemTouchHelper = new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(ItemTouchHelper.START | ItemTouchHelper.END, 0) {
#Override
public boolean onMove(#NonNull RecyclerView recyclerView, #NonNull RecyclerView.ViewHolder viewHolder, #NonNull RecyclerView.ViewHolder target) {
int fromPosition = viewHolder.getAdapterPosition();
int toPosition = target.getAdapterPosition();
Collections.swap(getData(), fromPosition, toPosition);
recyclerView.getAdapter().notifyItemMoved(fromPosition, toPosition);
return false;
}
#Override
public void onSwiped(#NonNull RecyclerView.ViewHolder viewHolder, int direction) {
}
});
itemTouchHelper.attachToRecyclerView(recyclerViewFreshwater);
return root;
}
private List<Biotope> getData() {
BiotopeDatabase database = BiotopeDatabase.getDbInstance(requireContext().getApplicationContext());
BiotopeDao biotopeDao = database.biotopeDao();
return biotopeDao.getAll();
}
}

Ideal Way to do this to create all UI component in Fragment not in the adapter . Create an interface to handle events in the fragment and provide callback to the fragment from adapter. now your Fragment should create all the UI component .
Now coming to the
How to provide callback from dialog fragment to Fragment.
You can use setTargetFragment but its deprecated . Now you can use setFragmentResultListener instead of setTargetFragment(), its the safest way i think. Once you get the result back in fragment you can call any method of your adapter.

Cannot cast onItem clicklistener inside Fragment Class form Adapter Class

I have an Fragment with recycleview where I populate it with json items from internet.
It load fine and Next step I want to is open new Activity when any row is clicked. It works in activity, thus I modified the same code for fragment but for fragment it throws exception in line
mExampleAdapter.setOnItemClickListener(getActivity());
with errror setOnItemClickListener of refrence adatper cannot be applied to Fragment activty and thus when I change line to
(ExampleAdapter.OnItemClickListener)
and when i build and run . Then app crashes with error that Mainactivity which holds framgnet cannot be cast in to .ExampleAdapter$OnItemClickListener
Here is my whole Fragment class
public class Mynotes extends Fragment implements ExampleAdapter.OnItemClickListener{
public static final String YTD_LINK = "link";
private RecyclerView mRecyclerView;
private ExampleAdapter mExampleAdapter;
private ArrayList<ExampleItem> mExampleList;
private RequestQueue mRequestQueue;
String url="https://api.myjson.com/bins/16mecx";
public Mynotes() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.activity_jsonfeed, container, false);
mRecyclerView = view.findViewById(R.id.recycler_view);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
mRecyclerView.addItemDecoration(new MyDividerItemDecoration(getActivity(), DividerItemDecoration.VERTICAL, 36));
mExampleList = new ArrayList<>();
mExampleAdapter = new ExampleAdapter(getActivity(), mExampleList);
mRecyclerView.setAdapter(mExampleAdapter);
mExampleAdapter.setOnItemClickListener((ExampleAdapter.OnItemClickListener) getActivity());
parseJSON();
return view;
}
private void parseJSON() {
JsonObjectRequest request = new JsonObjectRequest(Request.Method.GET, url, null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
myProgressBar.setVisibility(View.GONE);
try {
JSONArray jsonArray = response.getJSONArray("hits");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject hit = jsonArray.getJSONObject(i);
String videoTitle = hit.getString("title");
String link = hit.getString("link");
mExampleList.add(new ExampleItem(videoTitle, link));
mExampleAdapter.notifyDataSetChanged();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
mRequestQueue.add(request);
}
#Override
public void onItemClick(int position) {
Intent intent = new Intent(getActivity(), NewActiviyt.class);
ExampleItem clickedItem = mExampleList.get(position);
intent.putExtra(YTD_LINK, clickedItem.getmLink());
startActivity(intent);
}
#Override
public void onRefresh() {
}
}
and my Adapter Class is
public class ExampleAdapter extends RecyclerView.Adapter<ExampleAdapter.ExampleViewHolder> {
private Context mContext;
private ArrayList<ExampleItem> mExampleList;
private OnItemClickListener mListener;
public interface OnItemClickListener {
void onItemClick(int position);
}
public void setOnItemClickListener(OnItemClickListener listener) {
mListener = listener;
}
public ExampleAdapter(Context context, ArrayList<ExampleItem> exampleList) {
mContext = context;
mExampleList = exampleList;
}
#Override
public ExampleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(mContext).inflate(R.layout.example_item, parent, false);
return new ExampleViewHolder(v);
}
#Override
public void onBindViewHolder(ExampleViewHolder holder, int position) {
ExampleItem currentItem = mExampleList.get(position);
String title = currentItem.getTitle();
// int likeCount = currentItem.getLikeCount();
// String imageUrl = currentItem.getImageUrl();
holder.mTextViewCreator.setText(title);
// holder.mTextViewLikes.setText("Likes: " + likeCount);
// Glide.with(mContext).load(imageUrl).apply(RequestOptions.circleCropTransform()).into(holder.mImageView);
}
#Override
public int getItemCount() {
return mExampleList.size();
}
public class ExampleViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
public TextView mTextViewCreator;
// public TextView mTextViewLikes;
// public ImageView mImageView;
public ExampleViewHolder(View itemView) {
super(itemView);
// mTextViewLikes = itemView.findViewById(R.id.text_view_likes);
// mImageView = itemView.findViewById(R.id.image_view);
mTextViewCreator = itemView.findViewById(R.id.text_title);
}
#Override
public void onClick(View view) {
if (mListener != null) {
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION) {
mListener.onItemClick(position);
}
}
}
}
}
Thanks in advance.

replace getActivity with getContext when you work in fragment,
You can read more here
What is different between getContext and getActivity from Fragment in support library?

Your activity should implement ExampleAdapter.OnItemClickListener

Fragment "overwrites" another fragment when first selected

I have Bottom Navigation with which I switch between 3 fragments: "ConnectFragment", "DashboardFragment" and "ChatFragment".
Switching from Connect to Chat and vice versa works OK, but when I select Dashboard it causes a bug that makes Dashboard appear when selecting Chat in navigation, what is causing this?
All 3 fragments have identical functionality and layout, so i assume the problem lays in MainActivity.
MainActivity:
public class MainActivity extends AppCompatActivity implements DashboardFragment.FragmentDashListener, ChatFragment.FragmentChatListener, ConnectFragment.FragmentConnListener {
FragmentManager fm = getSupportFragmentManager();
Fragment active;
Fragment FragmentConnect = new ConnectFragment();
Fragment FragmentDashboard = new DashboardFragment();
Fragment FragmentChat = new ChatFragment();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
BottomNavigationView bottomNav = findViewById(R.id.bottom_navigation);
bottomNav.setOnNavigationItemSelectedListener(navListener);
fm.beginTransaction().add(R.id.fragment_container, FragmentChat).hide(FragmentChat).commit(); //Ustvari vse 3 fragmente, skrije 2 da se nena vedno znova kreirajo
fm.beginTransaction().add(R.id.fragment_container, FragmentDashboard).hide(FragmentDashboard).commit();
fm.beginTransaction().add(R.id.fragment_container, FragmentConnect).commit();
}
private BottomNavigationView.OnNavigationItemSelectedListener navListener = new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem menuItem) {
active = FragmentConnect;
switch (menuItem.getItemId()) {
case R.id.nav_connect:
fm.beginTransaction().hide(active).show(FragmentConnect).commit();
active = FragmentConnect;
return true;
case R.id.nav_dashboard:
fm.beginTransaction().hide(active).show(FragmentDashboard).commit();
active = FragmentDashboard;
return true;
case R.id.nav_send:
fm.beginTransaction().hide(active).show(FragmentChat).commit();
active = FragmentChat;
return true;
}
return false;
}
};
#Override
public void onInputChatSent(CharSequence input) {
ConnectFragment.updateEditText(input);
}
#Override
public void onInputConnSent(CharSequence input) {
DashboardFragment.updateEditText(input);
}
#Override
public void onInputDashSent(CharSequence input) {
ChatFragment.updateEditText(input);
}
}
Fragments:
All 3 fragments have identical code, below are Dashboard and Chat.
public class DashboardFragment extends Fragment {
private FragmentDashListener listener;
private static EditText editText;
private Button ButtonOk;
public interface FragmentDashListener{
void onInputDashSent (CharSequence input);
}
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_dashboard, container, false);
editText = v.findViewById(R.id.edit_text);
ButtonOk = v.findViewById(R.id.Button_Ok);
ButtonOk.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
CharSequence input = editText.getText();
listener.onInputDashSent(input);
}
});
return v;
}
public static void updateEditText(CharSequence newText){
editText.setText(newText);
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if(context instanceof FragmentDashListener){
listener = (FragmentDashListener) context;
} else {
throw new RuntimeException(context.toString()+"must implement FragmentDashListener");
}
}
}
public class ChatFragment extends Fragment {
private FragmentChatListener listener;
private static EditText editText;
private Button ButtonOk;
public interface FragmentChatListener{
void onInputChatSent (CharSequence input);
}
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_chat, container, false);
editText = v.findViewById(R.id.edit_text);
ButtonOk = v.findViewById(R.id.Button_Ok);
ButtonOk.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
CharSequence input = editText.getText();
listener.onInputChatSent(input);
}
});
return v;
}
public static void updateEditText(CharSequence newText){
editText.setText(newText);
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if(context instanceof FragmentChatListener){
listener = (FragmentChatListener) context;
} else {
throw new RuntimeException(context.toString()+"must implement FragmentChatListener");
}
}
}

Remove the first line
active = FragmentConnect;
from onNavigationItemSelected method. This will fix the issue
or modify it as below
if(active == null) {
active = FragmentConnect;
}

New fetch data is not show on recycler list when pull down to refresh

I want to implement one code where data will come on Scroll and if the data is add on list then we pull down(SwipeRefreshLayout) the new data will come on that list. In my below code the add on data is coming in response but not come in list? I have read many tutorials like this but data is coming on Swipe refresh but not shown on list. Thank you in advance
public class UpdatesFragment extends Fragment implements SwipeRefreshLayout.OnRefreshListener{
SwipeRefreshLayout mSwipeRefreshLayout;
UserSessionManager session;
private List<SuperHero> listSuperHeroes;
private RecyclerView recyclerView;
private RecyclerView.LayoutManager layoutManager;
private RecyclerView.Adapter adapter;
public ProgressBar progressBar;
public String user_id;
TextView textView;
FloatingActionButton fab;
public int a=1;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view= inflater.inflate(R.layout.fragment_updates, container, false);
session = new UserSessionManager(getActivity());
// get user data from session
HashMap<String, String> user = session.getUserDetails();
user_id = user.get(UserSessionManager.KEY_USER_ID);
// SwipeRefreshLayout
mSwipeRefreshLayout = (SwipeRefreshLayout) view.findViewById(R.id.swipe_container);
mSwipeRefreshLayout.setOnRefreshListener(this);
mSwipeRefreshLayout.setColorSchemeResources(R.color.colorPrimary,
android.R.color.holo_green_dark,
android.R.color.holo_orange_dark,
android.R.color.holo_blue_dark);
/**
* Showing Swipe Refresh animation on activity create
* As animation won't start on onCreate, post runnable is used
*/
mSwipeRefreshLayout.post(new Runnable() {
#Override
public void run() {
mSwipeRefreshLayout.setRefreshing(true);
// Fetching data from server
getDataFromServer(1);
}
});
return view;
}
public void onViewCreated(View v, Bundle savedInstanceState) {
super.onViewCreated(v, savedInstanceState);
fab = (FloatingActionButton)v.findViewById(R.id.fab);
recyclerView = (RecyclerView) v.findViewById(R.id.updatesRecycler);
recyclerView.setHasFixedSize(true);
layoutManager = new LinearLayoutManager(getContext());
recyclerView.setLayoutManager(layoutManager);
listSuperHeroes = new ArrayList<>();
adapter = new CardAdapter(listSuperHeroes, getActivity());
recyclerView.setAdapter(adapter);
textView = (TextView)v.findViewById(R.id.text);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(getContext(), AddWebPostActivity.class);
startActivity(i);
}
});
getDataFromServer(a);
recyclerView.setOnScrollListener(new EndlessRecyclerOnScrollListener((LinearLayoutManager) layoutManager) {
#Override
public void onLoadMore(int current_page) {
getDataFromServer(current_page);
}
});
}
public void getDataFromServer(int requestCount) {
Log.e("count",String.valueOf(requestCount));
final String DATA_URL = "https://XYZ.php?username="+user_id + "&page="+requestCount;
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(DATA_URL,
new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
mSwipeRefreshLayout.setRefreshing(false);
Log.e("URL___________",DATA_URL);
Log.e("response___________", String.valueOf(response));
parseData(response);
adapter.notifyDataSetChanged();
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getContext(), "No More Items Available", Toast.LENGTH_SHORT).show();
}
});
RequestQueue requestQueue = Volley.newRequestQueue(getContext());
requestQueue.getCache().clear();
requestQueue.add(jsonArrayRequest);
}
private void parseData(JSONArray array) {
for (int i = 0; i < array.length(); i++) {
SuperHero superHero = new SuperHero();
JSONObject json = null;
try {
json = array.getJSONObject(i);
superHero.setPost_title(json.getString(Config.TAG_POST_TITLE));
superHero.setPost_content(json.getString(Config.TAG_POST_CONTENT));
superHero.setPost_parent(json.getString(Config.TAG_POST_PARENT));
superHero.setPost_date(json.getString(Config.TAG_POST_DATE));
superHero.setPost_date_gmt(json.getString(Config.TAG_POST_DATE_GMT));
superHero.setScheduled_date(json.getString(Config.TAG_SCHEDULED_DATE));
superHero.setTo_ping(json.getString(Config.TAG_IP_ADDRESS));
superHero.setVisit_post(json.getString(Config.TAG_VISIT_POST));
superHero.setUr_id(json.getString(Config.TAG_UR_ID));
} catch (JSONException e) {
e.printStackTrace();
}
listSuperHeroes.add(superHero);
}
}
/**
* Called when a swipe gesture triggers a refresh.
*/
#Override
public void onRefresh() {
getDataFromServer(1);
}
}
Adapter
public class CardAdapter extends RecyclerView.Adapter<CardAdapter.ViewHolder> {
UserSessionManager session;
public String user_id;
public String ur_id;
private Context context;
//String visit;
//List to store all superheroes
List<SuperHero> superHeroes;
//Constructor of this class
public CardAdapter(List<SuperHero> superHeroes, Context context){
super();
//Getting all superheroes
this.superHeroes = superHeroes;
this.context = context;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.web_post, parent, false);
// Session class instance
session = new UserSessionManager(context);
session.checkLogin();
// get user data from session
HashMap<String, String> user = session.getUserDetails();
user_id = user.get(UserSessionManager.KEY_USER_ID);
ViewHolder viewHolder = new ViewHolder(v);
return viewHolder;
}
#Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
//Getting the particular item from the list
final SuperHero superHero = superHeroes.get(position);
holder.tvPostTitle.setText(superHero.getPost_title());
holder.tvPostContent.setText(superHero.getPost_content());
holder.tvPostDateTime1.setText(superHero.getPost_date() +" / " +superHero.getPost_date_gmt());
final String visit = superHero.getVisit_post();
holder.tvVisitPost.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent i = new Intent(context,VisitWebView.class);
i.putExtra("visitURL",visit);
context.startActivity(i);
}
});
}
#Override
public int getItemCount() {
return superHeroes.size();
}
#Override
public int getItemViewType(int position) {
return position;
}
class ViewHolder extends RecyclerView.ViewHolder{
//Views
public TextView tvPostTitle,tvPostContent,tvPostDateTime1,tvVisitPost;
public ImageButton removeButton;
//Initializing Views
public ViewHolder(final View itemView) {
super(itemView);
tvPostTitle = (TextView) itemView.findViewById(R.id.tvPostTitle);
tvPostContent = (TextView) itemView.findViewById(R.id.tvPostContent);
tvPostDateTime1 = (TextView) itemView.findViewById(R.id.tvPostDateTime1);
tvVisitPost = (TextView) itemView.findViewById(R.id.tvVisitPost);
removeButton = (ImageButton) itemView.findViewById(R.id.removeButton);
}
}
}

use this method
mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
mSwipeRefreshLayout.setRefreshing(true);
getDataFromServer(1);
}
instead of this
mSwipeRefreshLayout.post(new Runnable() {
#Override
public void run() {
mSwipeRefreshLayout.setRefreshing(true);
// Fetching data from server
getDataFromServer(1);
}
});

Please call adapter and pass fresh list data after this line
listSuperHeroes.add(superHero) in parseData(response) function ;
adapter = new CardAdapter(listSuperHeroes, getActivity());
recyclerView.setAdapter(adapter)
adapter.notifyDataSetChanged();