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Nothing happens after I click item in recyclerview even after using interface

I have made an android application using java, and I have made a click listener interface but nothing seems to happen and I can't figure out what is wrong with my code. Please help.
Following is the code of my recyclerViewAdapter:
package com.example.ashwamedh.adapter;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import com.example.ashwamedh.R;
import com.example.ashwamedh.model.AdminConfirmation;
import com.example.ashwamedh.model.Attendance;
import com.example.ashwamedh.model.Confirmation;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.firebase.firestore.CollectionReference;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.QueryDocumentSnapshot;
import com.google.firebase.firestore.QuerySnapshot;
import java.util.List;
import java.util.Objects;
public class ManageAttendanceRecyclerViewAdapter extends RecyclerView.Adapter<ManageAttendanceRecyclerViewAdapter.ViewHolder> {
private List<Confirmation> practiceList;
private Context context;
private OnAttendanceClickListener onAttendanceClickListener;
private CollectionReference collectionReference = FirebaseFirestore.getInstance().collection("Users");
public ManageAttendanceRecyclerViewAdapter(List<Confirmation> practiceList, Context context, OnAttendanceClickListener onAttendanceClickListener) {
this.practiceList = practiceList;
this.context = context;
this.onAttendanceClickListener = onAttendanceClickListener;
}
#NonNull
#Override
public ManageAttendanceRecyclerViewAdapter.ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context)
.inflate(R.layout.manage_attendance_row, parent, false);
return new ViewHolder(view, context);
}
#Override
public void onBindViewHolder(#NonNull ManageAttendanceRecyclerViewAdapter.ViewHolder holder, int position) {
Confirmation confirmation = practiceList.get(position);
holder.nameTextView.setText(confirmation.getUsername());
if (confirmation.getRemarkOrReason() == "") {
holder.remarkOrReasonTextView.setText("null");
}else {
holder.remarkOrReasonTextView.setText(confirmation.getRemarkOrReason());
}
if (Objects.equals(confirmation.getConfirmation(), "present")) {
holder.confirmation.setImageResource(R.drawable.ic_baseline_check_24);
} else if (Objects.equals(confirmation.getConfirmation(), "absent")){
holder.confirmation.setImageResource(R.drawable.ic_baseline_close_24);
}
}
#Override
public int getItemCount() {
return practiceList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private TextView nameTextView;
private ImageView confirmation;
private TextView remarkOrReasonTextView;
OnAttendanceClickListener onAttendanceClickListener;
public ViewHolder(#NonNull View itemView, Context ctx) {
super(itemView);
this.onAttendanceClickListener = ManageAttendanceRecyclerViewAdapter.this.onAttendanceClickListener;
context = ctx;
nameTextView = itemView.findViewById(R.id.manage_attendance_name_textview);
confirmation = itemView.findViewById(R.id.manage_attendance_confirmation);
remarkOrReasonTextView = itemView.findViewById(R.id.manage_attendance_remark_reason_textview);
}
#Override
public void onClick(View view) {
int id = view.getId();
switch (id){
case R.id.manage_attendance_row:
Log.d("from recycler view", "onClick: " + "row clicked");
Confirmation confirmation = practiceList.get(getAdapterPosition());
String userId = confirmation.getUserId();
onAttendanceClickListener.OnAttendanceClick(userId);
}
}
}
}
Following is the code of OnAttendanceClickListener:
package com.example.ashwamedh.adapter;
public interface OnAttendanceClickListener {
void OnAttendanceClick(String userId);
}
Following is the code of the activity where the recycler view is used and the interface implemented:
package com.example.ashwamedh;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.cardview.widget.CardView;
import androidx.core.content.ContextCompat;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.content.Intent;
import android.content.res.ColorStateList;
import android.os.Bundle;
import android.util.Log;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;
import com.example.ashwamedh.adapter.ManageAttendanceRecyclerViewAdapter;
import com.example.ashwamedh.adapter.OnAttendanceClickListener;
import com.example.ashwamedh.model.Confirmation;
import com.example.ashwamedh.util.UserApi;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.android.material.bottomnavigation.BottomNavigationView;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.firebase.firestore.CollectionReference;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.QueryDocumentSnapshot;
import com.google.firebase.firestore.QuerySnapshot;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
import java.util.Objects;
public class ManagePracticeConfirmationActivity extends AppCompatActivity implements OnAttendanceClickListener {
private static final String TAG = "PRACTICE_CONFIRMATION";
private RecyclerView recyclerView;
private BottomNavigationView bottomNavigationView;
private CardView markAttendanceCardView;
private FloatingActionButton presentFab;
private FloatingActionButton absentFab;
private Button updateButton;
private TextView noPracticeTextView;
private ImageButton signOut;
private Boolean isAdmin;
private String attendance;
private ManageAttendanceRecyclerViewAdapter manageAttendanceRecyclerViewAdapter;
private String practiceDate;
private List<Confirmation> practiceList;
private FirebaseFirestore db = FirebaseFirestore.getInstance();
private CollectionReference collectionReference = db.collection("Confirmations");
private CollectionReference userCollection = db.collection("Users");
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_manage_practice_confirmation);
Objects.requireNonNull(getSupportActionBar()).hide();
practiceList = new ArrayList<>();
recyclerView = findViewById(R.id.manage_attendance_recycler_view);
bottomNavigationView = findViewById(R.id.bottomNavigationView);
markAttendanceCardView = findViewById(R.id.mark_attendance_cardView);
presentFab = findViewById(R.id.present_fab);
absentFab = findViewById(R.id.absent_fab);
updateButton = findViewById(R.id.update_attendance_button);
noPracticeTextView = findViewById(R.id.no_practice_textView);
signOut = findViewById(R.id.signOut_manage_attendance);
absentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.absent_button_color)));
presentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.present_button_color)));
bottomNavigationView.setSelectedItemId(R.id.manage_practice_confirmation_button);
markAttendanceCardView.setVisibility(View.INVISIBLE);
UserApi userApi = UserApi.getInstance();
isAdmin = Objects.equals(userApi.getUsername(), "ADMIN");
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
attendance = "";
Date today = Calendar.getInstance().getTime();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("dd/MM/yyyy");
practiceDate = simpleDateFormat.format(today);
Log.d(TAG, "onCreate: " + Calendar.DAY_OF_WEEK);
if (Calendar.getInstance().get(Calendar.DAY_OF_WEEK) == Calendar.SATURDAY
|| Calendar.getInstance().get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {
recyclerView.setVisibility(View.INVISIBLE);
noPracticeTextView.setVisibility(View.VISIBLE);
} else {
recyclerView.setVisibility(View.VISIBLE);
noPracticeTextView.setVisibility(View.INVISIBLE);
}
bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
if (item.getItemId() == R.id.home_button) {
Intent intent = new Intent(ManagePracticeConfirmationActivity.this, Dashboard.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
finish();
return true;
}
if (item.getItemId() == R.id.council_button) {
Intent intent = new Intent(ManagePracticeConfirmationActivity.this, CouncilActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
finish();
return true;
}
if (item.getItemId() == R.id.attendance_button) {
Intent intent = new Intent(ManagePracticeConfirmationActivity.this, BatchmateAttendance.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
finish();
return true;
}
if (item.getItemId() == R.id.manage_practice_confirmation_button) {
return true;
}
return false;
}
});
}
#Override
protected void onStart() {
super.onStart();
Date today = Calendar.getInstance().getTime();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("dd/MM/yyyy");
practiceDate = simpleDateFormat.format(today);
collectionReference.whereEqualTo("practiceDate", practiceDate)
.get()
.addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
#Override
public void onSuccess(QuerySnapshot queryDocumentSnapshots) {
if (!queryDocumentSnapshots.isEmpty()) {
for (QueryDocumentSnapshot snapshot : queryDocumentSnapshots) {
Confirmation confirmation = snapshot.toObject(Confirmation.class);
practiceList.add(confirmation);
}
manageAttendanceRecyclerViewAdapter = new ManageAttendanceRecyclerViewAdapter(practiceList,
ManagePracticeConfirmationActivity.this,
ManagePracticeConfirmationActivity.this);
recyclerView.setAdapter(manageAttendanceRecyclerViewAdapter);
manageAttendanceRecyclerViewAdapter.notifyDataSetChanged();
}
}
})
.addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
}
});
}
#Override
public void OnAttendanceClick(String userId) {
Log.d(TAG, "OnAttendanceClick: "+ isAdmin);
UserApi userApi = UserApi.getInstance();
isAdmin = Objects.equals(userApi.getUsername(), "ADMIN");
if (isAdmin) {
markAttendanceCardView.setVisibility(View.VISIBLE);
presentFab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
attendance = "present";
presentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.selected_button_color)));
absentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.absent_button_color)));
}
});
absentFab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
attendance = "absent";
absentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.selected_button_color)));
presentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.present_button_color)));
}
});
updateButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Confirmation confirmation = new Confirmation();
confirmation.setUserId(userId);
confirmation.setConfirmation(attendance);
confirmation.setPracticeDate(practiceDate);
if (Objects.equals(attendance, "present")) {
confirmation.setRemarkOrReason("PRESENT ON PRACTICE");
} else if (Objects.equals(attendance, "absent")){
confirmation.setRemarkOrReason("ABSENT ON PRACTICE");
}
SimpleDateFormat documentDateFormat = new SimpleDateFormat("dd_MM_yyyy");
String docDate = documentDateFormat.format(practiceDate);
String docAddress = userId+"_"+docDate;
collectionReference.document(docAddress)
.set(confirmation)
.addOnSuccessListener(new OnSuccessListener<Void>() {
#Override
public void onSuccess(Void unused) {
Toast.makeText(ManagePracticeConfirmationActivity.this, "Attendance marked!", Toast.LENGTH_SHORT)
.show();
}
});
attendance = "";
absentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.absent_button_color)));
presentFab.setBackgroundTintList(ColorStateList.valueOf(ContextCompat.getColor(ManagePracticeConfirmationActivity.this, R.color.present_button_color)));
markAttendanceCardView.setVisibility(View.INVISIBLE);
manageAttendanceRecyclerViewAdapter.notifyDataSetChanged();
}
});
} else {
Toast.makeText(ManagePracticeConfirmationActivity.this, "Only admins can mark attendance!", Toast.LENGTH_SHORT)
.show();
}
}
}
Please help me I am clueless of where is the error

RecyclerView clicks doesn't work like that.
Firstly you should write click event in onBindViewHolder
holder.itemView.setOnClickListener(view -> onAttendanceClickListener.OnAttendanceClick(userId));
Put this code in your onBindViewHolder and you are good to go!
You will receive click events in Activity.

Calculating Price * Quantity from Adapter to Total Price from Activity

I want to get total price in Activity from Price and Quantity in Adapter, it's mean like qty * price = total_price.
Here is my Adapter for handling the list of Items Activity:
package com.example.aulaherbalfinal.Adapter;
import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import com.example.aulaherbalfinal.Model.DataModel;
import com.example.aulaherbalfinal.R;
import java.text.NumberFormat;
import java.util.List;
import java.util.Locale;
public class AdapterDataPembelian extends RecyclerView.Adapter<AdapterDataPembelian.HolderDataPembelian>{
private Context ctx;
private List<DataModel> listDataPembelian;
private int count;
public AdapterDataPembelian(Context ctx, List<DataModel> listDataPembelian) {
this.ctx = ctx;
this.listDataPembelian = listDataPembelian;
}
#NonNull
#Override
public HolderDataPembelian onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View layout = LayoutInflater.from(parent.getContext()).inflate(R.layout.card_item_pembelian, parent, false);
HolderDataPembelian holder = new HolderDataPembelian(layout);
return holder;
}
#Override
public void onBindViewHolder(#NonNull HolderDataPembelian holder, int position) {
DataModel dm = listDataPembelian.get(position);
holder.tvId.setText(String.valueOf(dm.getId()));
holder.tvBarang.setText(dm.getBarang());
holder.tvStok.setText("Stok : "+String.valueOf(dm.getStok()));
holder.tvHarga.setText(formatRupiah(Double.parseDouble(String.valueOf(dm.getHarga()))));
holder.jmlBarang.setText(String.valueOf(dm.getQuantity()));
//holder.totalHarga.setText(String.valueOf(dm.getTotalHarga()));
Intent intent = new Intent("custom-message");
holder.btnRemove.setOnClickListener(v -> {
minusCartItem(holder,listDataPembelian.get(position));
});
holder.btnAdd.setOnClickListener(v -> {
plusCartItem(holder,listDataPembelian.get(position));
});
}
private void plusCartItem(HolderDataPembelian holder, DataModel dataModel) {
dataModel.setQuantity(dataModel.getQuantity()+1);
//dataModel.setTotalHarga(Integer.parseInt(String.valueOf(dataModel.getQuantity()*Double.parseDouble(String.valueOf(dataModel.getHarga())))));
holder.jmlBarang.setText(new StringBuilder().append(dataModel.getQuantity()));
}
private void minusCartItem(HolderDataPembelian holder, DataModel dataModel) {
if (dataModel.getQuantity() > 0){
dataModel.setQuantity(dataModel.getQuantity()-1);
//dataModel.setTotalHarga(Integer.parseInt(String.valueOf(dataModel.getQuantity()*Double.parseDouble(String.valueOf(dataModel.getHarga())))));
holder.jmlBarang.setText(new StringBuilder().append(dataModel.getQuantity()));
} else {
holder.jmlBarang.setText("0");
}
}
#Override
public int getItemCount() {
return listDataPembelian.size();
}
public class HolderDataPembelian extends RecyclerView.ViewHolder {
TextView tvId, tvBarang, tvStok, tvHarga;
Button btnAdd, btnRemove;
TextView jmlBarang, totalHarga;
public HolderDataPembelian(#NonNull View itemView) {
super(itemView);
tvId = itemView.findViewById(R.id.tv_id);
tvBarang = itemView.findViewById(R.id.tv_barang);
tvStok = itemView.findViewById(R.id.tv_stok);
tvHarga = itemView.findViewById(R.id.tv_harga);
btnAdd = itemView.findViewById(R.id.btn_add);
btnRemove = itemView.findViewById(R.id.btn_remove);
jmlBarang = itemView.findViewById(R.id.jml_barang);
totalHarga = itemView.findViewById(R.id.total_harga);
}
}
private String formatRupiah(Double number){
Locale localeID = new Locale("IND", "ID");
NumberFormat numberFormat = NumberFormat.getCurrencyInstance(localeID);
String formatRupiah = numberFormat.format(number);
String[] split = formatRupiah.split(",");
int length = split[0].length();
return split[0].substring(0,2)+". "+split[0].substring(2,length);
}
public int getTotalPrice(){
int totalPrice = 0;
for (int i=0 i<listDataPembelian.size(); i++){
}
}
}
And here is my Activity
package com.example.aulaherbalfinal.Activity;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.cardview.widget.CardView;
import androidx.localbroadcastmanager.content.LocalBroadcastManager;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
import android.annotation.SuppressLint;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import com.example.aulaherbalfinal.API.APIRequestData;
import com.example.aulaherbalfinal.API.RetroServer;
import com.example.aulaherbalfinal.Adapter.AdapterDataPembelian;
import com.example.aulaherbalfinal.Model.DataModel;
import com.example.aulaherbalfinal.Model.ResponseModel;
import com.example.aulaherbalfinal.R;
import com.google.android.material.bottomnavigation.BottomNavigationView;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import java.util.ArrayList;
import java.util.List;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
public class PembelianActivity extends AppCompatActivity {
private RecyclerView rvData;
private RecyclerView.Adapter adData;
private RecyclerView.LayoutManager lmData;
private List<DataModel> listDataPembelian = new ArrayList<>();
private SwipeRefreshLayout srlData;
private ProgressBar pbData;
private TextView totalHarga;
private EditText jmlBarang;
#SuppressLint("ClickableViewAccessibility")
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_pembelian);
rvData = findViewById(R.id.rv_data);
lmData = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
rvData.setLayoutManager(lmData);
srlData = findViewById(R.id.srl_data);
pbData = findViewById(R.id.pb_data);
totalHarga = findViewById(R.id.total_harga);
jmlBarang = findViewById(R.id.jml_barang);
totalHarga = findViewById(R.id.total_harga);
//retrieveData();
CardView cvTotal = findViewById(R.id.cv_total);
rvData.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_MOVE){
cvTotal.setVisibility(View.INVISIBLE);
}
if (event.getAction() == MotionEvent.ACTION_UP){
cvTotal.setVisibility(View.VISIBLE);
}
return false;
}
});
BottomNavigationView bottom_navigation = findViewById(R.id.bottom_navigation);
bottom_navigation.setItemIconTintList(null);
bottom_navigation.setSelectedItemId(R.id.navigation_pembelian);
ImageView profile =findViewById(R.id.profile);
profile.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(PembelianActivity.this, ProfileActivity.class);
startActivity(intent);
finish();
}
});
bottom_navigation.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch ( (item.getItemId())){
case R.id.navigation_stok:
startActivity(new Intent(getApplicationContext(), MainActivity.class));
overridePendingTransition(0, 0);
return true;
case R.id.navigation_pembelian:
return true;
case R.id.navigation_penjualan:
startActivity(new Intent(getApplicationContext(), PenjualanActivity.class));
overridePendingTransition(0, 0);
return true;
}
return false;
}
});
srlData.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
srlData.setRefreshing(true);
retrieveData();
srlData.setRefreshing(false);
}
});
}
#Override
protected void onResume() {
super.onResume();
retrieveData();
}
public void retrieveData(){
pbData.setVisibility(View.VISIBLE);
APIRequestData ardData = RetroServer.konekRetrofit().create(APIRequestData.class);
Call<ResponseModel> tampildata = ardData.ardRetrieveData();
tampildata.enqueue(new Callback<ResponseModel>() {
#Override
public void onResponse(Call<ResponseModel> call, Response<ResponseModel> response) {
int kode = response.body().getKode();
String pesan = response.body().getPesan();
//Toast.makeText(MainActivity.this, "Kode : "+kode+" | Pesan : "+pesan, Toast.LENGTH_SHORT).show();
listDataPembelian = response.body().getData();
adData = new AdapterDataPembelian(PembelianActivity.this, listDataPembelian);
rvData.setAdapter(adData);
adData.notifyDataSetChanged();
pbData.setVisibility(View.INVISIBLE);
}
#Override
public void onFailure(Call<ResponseModel> call, Throwable t) {
Toast.makeText(PembelianActivity.this, "Gagal Menghubungi Server", Toast.LENGTH_SHORT).show();
pbData.setVisibility(View.INVISIBLE);
}
});
}
}
Here is my app

I would do something like this:
Create an Interface for your activity to implement:
public interface CallbackIF {
double tally(double amount, int quantity)
}
public class PembelianActivity extends AppCompatActivity implements CallbackIF {
#Override
public double tally(double amount, int quantity) {
return amount * quantity;
}
}
Then when you initialize your recyclerview adapter pass in the interface like so:
adData = new AdapterDataPembelian(PembelianActivity.this, listDataPembelian, PembelianActivity.this);
And change your constructor for the data adapter to be
private CallbackIF callback;
public AdapterDataPembelian(Context ctx, List<DataModel> listDataPembelian, CallbackIF callback) {
this.ctx = ctx;
this.listDataPembelian = listDataPembelian;
this.callback = callback;
}
Then in your onClicklistener for your list / wherever you want to trigger a tally just call
double value = callback.tally(amount, quantity);
If you have any questions please ask

how to move from a fragment to a new activity when i clicked an item of recyclerview?

I am using recyclerview in fragment dynamically, now i want to open new activity on click of items with the same object / item.
AllCoursesFeagment.java
package com.example.learningapp.ui.NavigationDrawer.AllCourses;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import com.example.learningapp.Adapters.AllCoursesMyAdapter;
import com.example.learningapp.Interface.APIinterface;
import com.example.learningapp.Models.CourseListModel;
import com.example.learningapp.R;
import com.example.learningapp.Responses.CourseListResponse;
import com.example.learningapp.RetrofitAPIs.RetrofitAPI;
import com.example.learningapp.utility.ConstantData;
import java.util.List;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
public class AllCoursesFragment extends Fragment {
private RecyclerView recyclerView;
private List<CourseListModel> courseListModelList;
public AllCoursesFragment() {
// Required empty public constructor
}
// TODO: Rename and change types and number of parameters
public static AllCoursesFragment newInstance() {
return new AllCoursesFragment();
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_all_courses,null);
recyclerView = view.findViewById(R.id.allCourseList_RV);
APIinterface apIinterface = RetrofitAPI.getClient().create(APIinterface.class);
Call<CourseListResponse> call = apIinterface.getAllCourses(ConstantData.AppKey);
call.enqueue(new Callback<CourseListResponse>() {
#Override
public void onResponse(Call<CourseListResponse> call, Response<CourseListResponse> response){
if (response.isSuccessful()){
courseListModelList = response.body().getCourseList();
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
recyclerView.setAdapter(new AllCoursesMyAdapter(getActivity(),courseListModelList));
}
}
#Override
public void onFailure(Call<CourseListResponse> call, Throwable t) {
Toast.makeText(getActivity(),"Something went wrong",Toast.LENGTH_LONG).show();
}
});
return view;
}
}
AllCoursesMyAdapter.java
This is my adapter class.
package com.example.learningapp.Adapters;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import com.example.learningapp.Activities.CheckoutActivity;
import com.example.learningapp.Models.CourseListModel;
import com.example.learningapp.R;
import java.util.List;
public class AllCoursesMyAdapter extends RecyclerView.Adapter<AllCoursesMyAdapter.RecyclerVH> {
Context context;
List<CourseListModel> courseListModelList;
public AllCoursesMyAdapter(Context context, List<CourseListModel> courseListModelList) {
this.context = context;
this.courseListModelList = courseListModelList;
}
#NonNull
#Override
public RecyclerVH onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.single_row_design_allcourses,parent,false);
return new RecyclerVH(view);
}
#Override
public void onBindViewHolder(#NonNull RecyclerVH holder, int position) {
final CourseListModel courseListModel = courseListModelList.get(position);
holder.courseTitle.setText(courseListModel.getCourseName());
holder.courseDesc.setText(courseListModel.getCourseDescription());
holder.buyBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
moveToNewActivity();
//Toast.makeText(context,"Item Clicked"+position,Toast.LENGTH_SHORT).show();
Intent intent = new Intent(context, CheckoutActivity.class);
intent.putExtra("coursetitle",courseListModel.getCourseName());
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);
}
});
}
private void moveToNewActivity () {
Activity activity = new Activity();
Intent i = new Intent(activity, CheckoutActivity.class);
context.startActivity(i);
((Activity) context).overridePendingTransition(0, 0);
}
#Override
public int getItemCount() {
return courseListModelList.size();
}
public class RecyclerVH extends RecyclerView.ViewHolder {
TextView courseTitle,courseDesc;
Button buyBtn;
public RecyclerVH(#NonNull View itemView) {
super(itemView);
courseTitle = itemView.findViewById(R.id.course_title);
courseDesc = itemView.findViewById(R.id.course_desc);
buyBtn = itemView.findViewById(R.id.btn_buycourse);
}
}
}
I'm gettng crashed when i clicked item
holder.buyBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
moveToNewActivity();
//Toast.makeText(context,"Item Clicked"+position,Toast.LENGTH_SHORT).show();
Intent intent = new Intent(context, CheckoutActivity.class);
intent.putExtra("coursetitle",courseListModel.getCourseName());
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);
}
});
Here i am using a stored list of objects and now i want to move to the new activity when i clicked on an item with given position, but i am not able to do that.

private void moveToNewActivity () {
Activity activity = new Activity(); //this is wrong, delete this
...
}
you can't and shouldn't create an instance of an activity like this, it's something the OS has to schedule and handle for you.
you already seem to have context defined somewhere, so that means:
private void moveToNewActivity () {
Intent i = new Intent(context, CheckoutActivity.class);
context.startActivity(i);
...
}
so that means:
#Override
public void onClick(View v) {
moveToNewActivity();
}

Recycler view does not show up

I am having problem with my recyclerview I builed an app in android studio which suppose to create contacts and watch their cards using cardview and recyclerview the issue is that the list of contacts is not shown instead I am seeing a white screen
so here is my code:
import android.net.sip.SipSession;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.recyclerview.widget.RecyclerView;
import com.squareup.picasso.Picasso;
import org.w3c.dom.Text;
import java.util.ArrayList;
import java.util.List;
/*Connect contact list to
*
* */
public class ContactAdapter extends RecyclerView.Adapter<ContactAdapter.ContactViewHolder> {
private List<Contact> contacts;
public ContactAdapter(List<Contact> contacts) {
this.contacts = contacts;
}
interface ContactsListener{
void onContactClicked(int position,View view);
}
ContactsListener listener;
public void setListener(ContactsListener listener){
this.listener=listener;
}
public class ContactViewHolder extends RecyclerView.ViewHolder {
ImageView contactpicture;
TextView contactname;
TextView contactphone;
TextView contactemail;
public ContactViewHolder(View itemview) {
super(itemview);
contactpicture = itemview.findViewById(R.id.card_image);
contactphone = itemview.findViewById(R.id.contact_email);
contactphone = itemview.findViewById(R.id.contact_phone);
contactname = itemview.findViewById(R.id.contact_name);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (listener != null)
listener.onContactClicked(getAdapterPosition(), view);
}
});
}
}
#Override
public ContactViewHolder onCreateViewHolder(ViewGroup parent,int viewType){
View view= LayoutInflater.from(parent.getContext()).inflate(R.layout.contact_layout,parent,false);
ContactViewHolder holder=new ContactViewHolder(view);
return holder;
}
#Override
public void onBindViewHolder(ContactViewHolder holder,int position){
Contact contact=contacts.get(position);
holder.contactpicture.setImageBitmap(contact.getPhoto());
holder.contactname.setText(contact.getName());
holder.contactphone.setText(contact.getPhone());
holder.contactemail.setText(contact.getEmail());
}
#Override
public int getItemCount(){
return contacts.size();
}
}
package com.example.b_safe;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import androidx.annotation.Nullable;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
/*Define the list of contacts*/
public class ContactsList extends Activity {
#Override
protected void onCreate(#Nullable Bundle saveInstanceState){
super.onCreate(saveInstanceState);
setContentView(R.layout.show_contacts_activity);//לבדוק שזה מתקיים
RecyclerView recyclerview=findViewById(R.id.contacts_list);
recyclerview.setHasFixedSize(true);
recyclerview.setLayoutManager(new LinearLayoutManager( this));//צריך להוסיף this
ContactManager manager=ContactManager.getInstance(this);
ContactAdapter adapter=new ContactAdapter(manager.getContacts());
recyclerview.setAdapter(adapter);
adapter.setListener(new ContactAdapter.ContactsListener() {
#Override
public void onContactClicked(int position, View view) {
}
});
}
}
package com.example.b_safe;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
/*Adds new member to the contacts list
*
*
* */
public class AddContactActivity extends AppCompatActivity{
Bitmap bitmap;
EditText nameEt,phone_numberEt,emailEt;
ImageView img;
final int CAMERA_REQUEST=1;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add_contact_activity);
nameEt=findViewById(R.id.name_input);
phone_numberEt=findViewById(R.id.phone_input);
emailEt=findViewById(R.id.email_input);
img=findViewById(R.id.photo_result);
Button takepicture=findViewById(R.id.take_pic);
takepicture.setOnClickListener(new View.OnClickListener() {//Activation
#Override
public void onClick(View v) {
Intent camera=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(camera,CAMERA_REQUEST);
}
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode==CAMERA_REQUEST&&resultCode==RESULT_OK){ //checks if results where properly
bitmap=(Bitmap)data.getExtras().get("data");
img.setImageBitmap(bitmap);//saving as contact's photo
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {//Load menu type
getMenuInflater().inflate(R.menu.contact_menu,menu);
return super.onCreateOptionsMenu(menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {//fulfill actions
switch(item.getItemId()){
case R.id.action_save:
AlertDialog.Builder builder=new AlertDialog.Builder(this);
builder.setTitle("Please confirm")
.setMessage("Would you like to save the following contact?")
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
Contact contact=new Contact(nameEt.getText().toString(),phone_numberEt.getText().toString(),emailEt.getText().toString(),bitmap);
ContactManager manager=ContactManager.getInstance(AddContactActivity.this);
manager.addContact(contact);//Manager saved data
//Data zeroing
nameEt.setText("");
phone_numberEt.setText("");
emailEt.setText("");
img.setImageBitmap(null);
}})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(AddContactActivity.this,"The conatct saved",Toast.LENGTH_SHORT).show();
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(AddContactActivity.this,"The conatct saved",Toast.LENGTH_SHORT).show();
}
}).show();
break;
case R.id.action_back:
finish();
}
return super.onOptionsItemSelected(item);//Loads activity
}
}
AdapterActivity is the subclass adapter AddContactActivity creates new contacts and the problem is with the ContactsList activity which holds the list and does not show up

How to send Data when cardview clicked to detail content

I try to passing data from cardview when clicked to DetailFragment, in this case I try to use interface in my adapter, but I get an error a null object reference in mOnItemClickListener.onClick(i).
I try to passing data from cardview when clicked to DetailFragment, in this case I try to use interface in my adapter.
I want to passing data to DetailMoviesFragment Class.
this is my CardviewMovieAdapter Class
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import com.bumptech.glide.Glide;
import com.bumptech.glide.request.RequestOptions;
import java.util.ArrayList;
public class CardviewMovieAdapter extends RecyclerView.Adapter<CardviewMovieAdapter.CardViewViewHolder> {
private ArrayList<Movie> listMovie;
Context context;
OnItemClickListener mOnItemClickListener;
public void setListMovie(ArrayList<Movie> listMovie) {
this.listMovie = listMovie;
}
public ArrayList<Movie> getListMovie() {
return listMovie;
}
public interface OnItemClickListener {
void onClick(int position);
}
public void setOnItemClickListener(final OnItemClickListener mItemClickListener) {
this.mOnItemClickListener = mItemClickListener;
}
public CardviewMovieAdapter(ArrayList<Movie> listMovie, Context context) {
this.listMovie = listMovie;
this.context = context;
}
#NonNull
#Override
public CardviewMovieAdapter.CardViewViewHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.list_movie, viewGroup,false);
return new CardViewViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull final CardviewMovieAdapter.CardViewViewHolder cardViewViewHolder, final int i) {
final Movie movie = listMovie.get(i);
Glide.with(cardViewViewHolder.itemView.getContext())
.load(movie.getImageMovie())
.apply(new RequestOptions().override(350, 550))
.into(cardViewViewHolder.imgPhoto);
cardViewViewHolder.tvTitle.setText(movie.getTitleMovie());
cardViewViewHolder.tvDesc.setText(movie.getDescription());
cardViewViewHolder.btnDetail.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(cardViewViewHolder.itemView.getContext(), "Detail "+
listMovie.get(cardViewViewHolder.getAdapterPosition()).getTitleMovie(), Toast.LENGTH_SHORT).show();
}
});
cardViewViewHolder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(cardViewViewHolder.itemView.getContext(), "Kamu Memilih "+movie.getTitleMovie(), Toast.LENGTH_SHORT).show();
mOnItemClickListener.onClick(i);
}
});
// cardViewViewHolder.itemView.setOnClickListener(new View.OnClickListener() {
// #Override
// public void onClick(View v) {
// Toast.makeText(cardViewViewHolder.itemView.getContext(), "Kamu Memilih "+movie.getTitleMovie(), Toast.LENGTH_SHORT).show();
// }
// });
}
#Override
public int getItemCount() {
return listMovie.size();
}
public class CardViewViewHolder extends RecyclerView.ViewHolder {
ImageView imgPhoto;
TextView tvTitle, tvDesc;
Button btnDetail;
public CardViewViewHolder(#NonNull View itemView) {
super(itemView);
imgPhoto = itemView.findViewById(R.id.img_item_photo);
tvTitle = itemView.findViewById(R.id.tv_title);
tvDesc = itemView.findViewById(R.id.tv_desc);
btnDetail = itemView.findViewById(R.id.btn_detail);
}
}
}
This is my MoviesFragment Class
import android.content.Intent;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.widget.CardView;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ListView;
import java.util.ArrayList;
/**
* A simple {#link Fragment} subclass.
*/
public class MoviesFragment extends Fragment implements View.OnClickListener{
private RecyclerView rvMovie;
private String[] dataMovieTitle;
private String[] dataDescription;
private TypedArray dataPhoto;
private ArrayList<Movie> movies;
Button btnDetail;
private CardviewMovieAdapter adapter;
View view;
final static String KEY = "KEY";
public MoviesFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
view = inflater.inflate(R.layout.fragment_movies, container, false);
//adapter = new CardviewMovieAdapter(movies,getContext());
rvMovie = view.findViewById(R.id.rv_movies);
prepare();
addItem();
showRecyclerCardView();
adapter = new CardviewMovieAdapter(movies, getContext());
adapter.setOnItemClickListener(new CardviewMovieAdapter.OnItemClickListener() {
#Override
public void onClick(int position) {
final Movie movie = movies.get(position);
DetailMoviesFragment detailMoviesFragment = new DetailMoviesFragment();
// Bundle mBundle = new Bundle();
// mBundle.putString(detailMoviesFragment.EXTRA_TITLE, movie.getTitleMovie());
// mBundle.putString(detailMoviesFragment.EXTRA_DESCRIPTION, movie.getDescription());
// mBundle.putInt(detailMoviesFragment.EXTRA_PHOTO, movie.getImageMovie());
// detailMoviesFragment.setArguments(mBundle);
MoviesFragment.newInstance(movie.getTitleMovie(), movie.getDescription(), movie.getImageMovie());
FragmentManager mFragmentManager = getFragmentManager();
if (mFragmentManager!= null) {
FragmentTransaction mFragmentTransaction = mFragmentManager.beginTransaction();
mFragmentTransaction.replace(R.id.containterFragment, detailMoviesFragment, DetailMoviesFragment.class.getSimpleName());
mFragmentTransaction.addToBackStack(null);
mFragmentTransaction.commit();
}
}
});
return view;
}
public static MoviesFragment newInstance(String title, String desc, int image) {
MoviesFragment moviesFragment = new MoviesFragment();
Bundle args = new Bundle();
args.putInt("image", image);
args.putString("title", title);
args.putString("desc", desc);
moviesFragment.setArguments(args);
return moviesFragment;
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
private void showRecyclerCardView(){
rvMovie.setLayoutManager(new LinearLayoutManager(getActivity()));
CardviewMovieAdapter adapter = new CardviewMovieAdapter(movies,getActivity());
rvMovie.setAdapter(adapter);
}
private void prepare() {
dataMovieTitle = getResources().getStringArray(R.array.data_movie_name);
dataDescription = getResources().getStringArray(R.array.data_desc_movie);
dataPhoto = getResources().obtainTypedArray(R.array.data_photo_movie);
}
private void addItem(){
movies = new ArrayList<>();
for (int i=0; i < dataMovieTitle.length; i++){
Movie movie = new Movie();
movie.setImageMovie(dataPhoto.getResourceId(i, -1));
movie.setTitleMovie(dataMovieTitle[i]);
movie.setDescription(dataDescription[i]);
movies.add(movie);
}
}
#Override
public void onClick(View v) {
if(v.getId() == R.id.card_view){
}
}
}
and this is DetailMoviesActivity Class
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import com.squareup.picasso.Picasso;
public class DetailMovieActivity extends AppCompatActivity {
Movie movie;
TextView tvTitle, tvDesc;
ImageView ivMovie;
Button btnDetail;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detail_movie);
initView();
}
private void initView() {
movie = (Movie) getIntent().getSerializableExtra("informasi");
String judul = movie.getTitleMovie();
String desc = movie.getDescription();
int img = movie.getImageMovie();
tvTitle.setText(judul);
tvDesc.setText(desc);
Picasso.get().load(img).into(ivMovie);
}
}

You can try with delete the setOnItemClickListener and call intent from cardViewViewHolder.itemView.setOnClickListener