Android application crashes when retrieving data from firebase real-time database

Question

When I fetch data from firebase real time database and try to store it in string variable, the application gets crashed. I want to display data in AlertDialog box. I've attached logcat image along with structure of database.

Declared variables:

String dayselected,name,slotdata;

Spinner code:

days.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        dayselected = daysArray[position];
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {

    }
});

Data search button code:

search.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        backbtn.setVisibility(View.GONE);
        logout.setEnabled(false);
        search.setEnabled(false);
        days.setEnabled(false);
        progressBar.setVisibility(View.VISIBLE);
        if(!TextUtils.isEmpty(facultyname.getText().toString())){
            DatabaseReference reference = FirebaseDatabase.getInstance().getReference().child(name).child(dayselected);
            reference.addValueEventListener(new ValueEventListener() {
                @Override
                public void onDataChange(@NonNull DataSnapshot snapshot) {
                    slotdata = snapshot.child("Slot1").getValue().toString() + "\n" +
                            snapshot.child("Slot2").getValue().toString() + "\n" +
                            snapshot.child("Slot3").getValue().toString() + "\n" +
                            snapshot.child("Slot4").getValue().toString() + "\n" +
                            snapshot.child("Slot5").getValue().toString() + "\n" +
                            snapshot.child("Slot6").getValue().toString();
                }

                @Override
                public void onCancelled(@NonNull DatabaseError error) {

                }
            });
            AlertDialog.Builder dialog = new AlertDialog.Builder(StudentLoggedIn.this);
            dialog.setTitle("Time Slots");
            dialog.setMessage(slotdata);
            dialog.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialogInterface, int which) {
                    dialogInterface.dismiss();
                }
            });
            AlertDialog alertDialog = dialog.create();
            alertDialog.show();
        }
        else {
            backbtn.setVisibility(View.VISIBLE);
            logout.setEnabled(true);
            search.setEnabled(true);
            days.setEnabled(true);
            progressBar.setVisibility(View.GONE);
            Toast.makeText(StudentLoggedIn.this, "Empty Faculty Name Field", Toast.LENGTH_SHORT).show();
        }
    }
});

Firebase Database: enter image description here

Logcat: enter image description here

Can you format your code a bit so that its clear to the viewers what's actually going on? — sinha-shaurya, May 09 '21 at 14:31
Does this answer your question? [Unfortunately MyApp has stopped. How can I solve this?](https://stackoverflow.com/questions/23353173/unfortunately-myapp-has-stopped-how-can-i-solve-this) — a_local_nobody, May 09 '21 at 15:13
If the application crashes there will be an error message and stack trace in its logcat output. Please find those, and add them to your question by clicking the `edit` link under it. — Frank van Puffelen, May 09 '21 at 15:16

Android application crashes when retrieving data from firebase real-time database

0 Answers0