FragmentAttendance

public class FragmentAttendance extends Fragment {

    DatabaseReference databaseReferenceEvent, databaseReferenceAttendance, databaseReferenceUser;
    ProgressBar progressBar;
    HelperProgressBar helperProgressBar;
    Button buttonAddEvent;
    TextView textKegiatanKosong;
    RecyclerView recyclerViewAttendance;
    FirebaseRecyclerAdapter<ModelEvent, ViewHolderEvent> adapter;
    String stringQR, stringQRDecrypt, stringNIPQR, stringValidation;
    String stringNama, stringNIP, stringJabatan, stringOPD, stringEmail, stringEventID, stringWaktu;

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.fragment_attendance, container, false);

        //Initialization
        buttonAddEvent = v.findViewById(R.id.button_add_event);
        progressBar = v.findViewById(R.id.progress_bar_attendance);
        recyclerViewAttendance = v.findViewById(R.id.recyclerAttendance);
        textKegiatanKosong = v.findViewById(R.id.text_kegiatan_kosong);


        helperProgressBar = new HelperProgressBar(getActivity(), progressBar);

        recyclerViewAttendance.setLayoutManager(new LinearLayoutManager(requireContext()));
        recyclerViewAttendance.setHasFixedSize(true);


        //Load Data
        SharedPreferences sharedPreferences = requireActivity().getSharedPreferences(SHARED_PREFERENCE_NAME, MODE_PRIVATE);
        stringEmail = sharedPreferences.getString(SHARED_EMAIL,"");
        stringNama = sharedPreferences.getString(SHARED_NAMA,"");
        stringNIP = sharedPreferences.getString(SHARED_NIP, "");
        stringJabatan = sharedPreferences.getString(SHARED_JABATAN, "");
        stringOPD = sharedPreferences.getString(SHARED_OPD, "");

        databaseReferenceEvent = FirebaseDatabase.getInstance().getReference("Event");
        databaseReferenceEvent.keepSynced(true);
        databaseReferenceAttendance = FirebaseDatabase.getInstance().getReference("Attendance");
        databaseReferenceAttendance.keepSynced(true);
        databaseReferenceUser = FirebaseDatabase.getInstance().getReference("Users");
        databaseReferenceUser.keepSynced(true);

        buttonAddEvent.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(getContext(), ActivityAddEvent.class));
            }
        });


        fetch();
        recyclerViewAttendance.setAdapter(adapter);

        Log.i(TAG, "On Create .....");
        return v;
    }


    //Attendance
    //Getting data
    private void fetch() {

        helperProgressBar.showProgressBar();
        Query query = databaseReferenceEvent.orderByChild("eventPenyelenggara").equalTo(stringOPD);

        query.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {
                if(!snapshot.exists()){
                    helperProgressBar.hideProgressBar();
                    textKegiatanKosong.setVisibility(View.VISIBLE);
                }
                if(snapshot.exists()) {
                    helperProgressBar.showProgressBar();
                    textKegiatanKosong.setVisibility(View.GONE);
                }
            }

            @Override
            public void onCancelled(@NonNull DatabaseError error) {
                Log.d(TAG, error.getMessage()); //Don't ignore errors!
            }
        });

        //Get Event data
        FirebaseRecyclerOptions <ModelEvent> options = new FirebaseRecyclerOptions.Builder<ModelEvent>().setQuery(query, snapshot -> new ModelEvent(
            Objects.requireNonNull(snapshot.child("eventID").getValue()).toString(),
            Objects.requireNonNull(snapshot.child("eventNama").getValue()).toString(),
            Objects.requireNonNull(snapshot.child("eventLokasi").getValue()).toString(),
            Objects.requireNonNull(snapshot.child("eventTanggal").getValue()).toString(),
            Objects.requireNonNull(snapshot.child("eventJam").getValue()).toString(),
            Objects.requireNonNull(snapshot.child("eventPenyelenggara").getValue()).toString(),
            Objects.requireNonNull(snapshot.child("eventStatus").getValue()).toString()))
        .build();

        //For View Holder
        adapter = new FirebaseRecyclerAdapter<ModelEvent, ViewHolderEvent>(options) {
            @NonNull
            @Override
            public ViewHolderEvent onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
                View view = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.list_attendance, parent, false);

                helperProgressBar.hideProgressBar();
                return new ViewHolderEvent(view);
            }

            //Set data on each list
            @Override
            protected void onBindViewHolder(@NonNull ViewHolderEvent viewHolderEvent, int i, @NonNull ModelEvent modelEvent) {
                viewHolderEvent.setStringKegiatan(modelEvent.getEventNama());
                viewHolderEvent.setStringTanggal(modelEvent.getEventTanggal());
                viewHolderEvent.setStringLokasi(modelEvent.getEventLokasi());
                viewHolderEvent.setStringStatus(modelEvent.getEventStatus());

                viewHolderEvent.buttonScan.setOnClickListener(v -> {
                    stringEventID = modelEvent.getEventID();

                    scanInitialization();
                });
            }
        };
    }

    //For Scanner
    //Scanner Initialization
    private void scanInitialization() {
        Log.i(TAG, "On Scanner Initialization.....");

        ScanOptions scanOption = new ScanOptions();
        scanOption.setDesiredBarcodeFormats(ScanOptions.ALL_CODE_TYPES); //Many type
        scanOption.setPrompt("Scan absen");
        scanOption.setOrientationLocked(true);
        scanOption.setBeepEnabled(true);
        fragmentLauncher.launch(scanOption);
    }

    //Scanner Launcher
    private final ActivityResultLauncher<ScanOptions> fragmentLauncher = registerForActivityResult(new ScanContract(),
            result -> {

                Log.i(TAG, "On Scanner Launcher.....");

                //On Backpress
                if(result.getContents() == null) {
                    Toast.makeText(getContext(), "Cancelled", Toast.LENGTH_LONG).show();
                }
                else {
                    //Get data from QRCode
                    stringQR = result.getContents();

                    //Decrypt data from QR
                    ModelDecrypt modelDecrypt = new ModelDecrypt(stringQR);
                    stringQRDecrypt = modelDecrypt.getDataDecrypt();

                    //There is a special String for the barcode to scan
                    if(stringQRDecrypt != null && stringQRDecrypt.contains(",")){
                        StringTokenizer tokenizer = new StringTokenizer(stringQRDecrypt, ",");
                        stringValidation = tokenizer.hasMoreTokens() ? tokenizer.nextToken() : null;
                        stringNIPQR = tokenizer.hasMoreTokens() ? tokenizer.nextToken() : null;

                        //AKB2017 is data validation from Home
                        assert stringValidation != null;
                        if(stringValidation.equals("AKB2017")){
                            //Get Data
                            //Get User Data from Users (userID);
                            getUserData();

                            //Put Data
                            //Put User data to Attendance (EventID)
                            setUserAttendance();


                            //Notification
                            Toast.makeText(getContext(), "Nama: " + stringNama, Toast.LENGTH_LONG).show();
                        }
                        else{
                            Toast.makeText(getContext(), "Data Barcode Tidak Valid", Toast.LENGTH_LONG).show();
                        }
                    }
                    else{
                        Toast.makeText(getContext(), "Bukan Barcode Absensi", Toast.LENGTH_LONG).show();
                    }
                }
            });

    private void setUserAttendance() {

        //Get current time
        Locale id = new Locale("in", "ID");
        SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MMMM/yyyy, HH:mm", id);
        stringWaktu = dateFormat.format(new Date());

        ModelAttendance attendance = new ModelAttendance(
                stringNama,
                stringNIP,
                stringJabatan,
                stringOPD,
                stringWaktu);

        databaseReferenceAttendance.child(stringEventID).child(stringNIP).setValue(attendance)
                .addOnSuccessListener(success -> {
                })
                .addOnFailureListener(e -> {
                    Log.d(TAG, e.getMessage()); //Don't ignore errors!
                });
    }

    private void getUserData() {
        databaseReferenceUser.child(stringNIPQR).addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {
                if(snapshot.exists()){
                    stringNama = Objects.requireNonNull(snapshot.child("userNama").getValue()).toString();
                    stringNIP = Objects.requireNonNull(snapshot.child("userNIP").getValue()).toString();
                    stringJabatan = Objects.requireNonNull(snapshot.child("userJabatan").getValue()).toString();
                    stringOPD = Objects.requireNonNull(snapshot.child("userOPD").getValue()).toString();
                }
            }
            @Override
            public void onCancelled(@NonNull DatabaseError error) {
                Log.d(TAG, error.getMessage()); //Don't ignore errors!
            }
        });
    }


    //Pressed return button - returns to home
    @Override
    public void onResume() {
        super.onResume();

        //Backpress
        FragmentHome fragmentHome = new FragmentHome();

        requireView().setFocusableInTouchMode(true);
        requireView().requestFocus();
        requireView().setOnKeyListener((v, keyCode, event) -> {

            if (event.getAction() == KeyEvent.ACTION_UP && keyCode == KeyEvent.KEYCODE_BACK){
                requireActivity().getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container, fragmentHome).commit();
                BottomNavigationView mBottomNavigationView = requireActivity().findViewById(R.id.bottom_navigation_view);
                mBottomNavigationView.setSelectedItemId(R.id.nav_home);
                return true;
            }
            return false;
        });
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Log.i(TAG, "On Destroy .....");
    }

    @Override
    public void onPause() {
        super.onPause();
        Log.i(TAG, "On Pause .....");
    }

    @Override
    public void onStart() {
        super.onStart();
        adapter.startListening();
        Log.i(TAG, "On Start .....");
    }

    @Override
    public void onStop() {
        super.onStop();
        adapter.stopListening();
        Log.i(TAG, "On Stop .....");
    }
}