When I click the register button then fetch NullPointerException like that kind of error
Process: com.example.swapno_samity, PID: 8406 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.swapno_samity/com.example.swapno_samity.MemberRegistration}: java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.firebase.database.DatabaseReference com.google.firebase.database.DatabaseReference.child(java.lang.String)' on a null object reference
> at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.firebase.database.DatabaseReference com.google.firebase.database.DatabaseReference.child(java.lang.String)' on a null object reference at com.example.swapno_samity.MemberRegistration.onCreate(MemberRegistration.java:40)
Here the code
public class MemberRegistration extends AppCompatActivity {
private EditText etName, etEmail, etDob, etPhoneNumber, etAddress, etIdCard, etPenCard, etAdarCard, etAmountOfLoan, etInterest;
private RadioGroup radioGroupGender;
private RadioButton etGender;
public FirebaseDatabase firebaseDatabase;
public DatabaseReference rootReference;
public DatabaseReference memberReference;
String memberId;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_member_registration);
getSupportActionBar().setTitle("Registration Form");
etName = findViewById(R.id.editText_register_full_name);
etEmail = findViewById(R.id.editText_register_email);
etDob = findViewById(R.id.editText_register_dob);
etPhoneNumber = findViewById(R.id.editText_register_mobile);
etAddress = findViewById(R.id.editText_register_adress);
etIdCard = findViewById(R.id.editText_register_IdCard);
etPenCard = findViewById(R.id.editText_register_PenCard);
etAdarCard = findViewById(R.id.editText_register_AdarCard);
etAmountOfLoan = findViewById(R.id.editText_register_AmountOfLoan);
etInterest = findViewById(R.id.editText_register_interestOfLoan);
radioGroupGender = findViewById(R.id.radio_group_register_gender);
radioGroupGender.clearCheck();
radioGroupGender.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
etGender = radioGroupGender.findViewById(checkedId);
}
});
Button registerMember = findViewById(R.id.button_register);
registerMember.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// obtain the entered data
String textName = etName.getText().toString();
String textEmail = etEmail.getText().toString();
String textDob = etDob.getText().toString();
String textAdress = etAddress.getText().toString();
String textPhoneNumber = etPhoneNumber.getText().toString();
String textIdCard = etIdCard.getText().toString();
String textPenCard = etPenCard.getText().toString();
String textAdarCard = etAdarCard.getText().toString();
String textAmount = etAmountOfLoan.getText().toString();
String textInterest = etInterest.getText().toString();
String textGender = etGender.getText().toString();
if (TextUtils.isEmpty(textName)) {
Toast.makeText(MemberRegistration.this, "Please Enter Your Full Name", Toast.LENGTH_SHORT).show();
etName.setError("Full Name Required");
etName.requestFocus();
}
if (TextUtils.isEmpty(textDob)) {
Toast.makeText(MemberRegistration.this, "Please Enter Date Of Birthday", Toast.LENGTH_SHORT).show();
etDob.setError("Date Of Birthday Required");
etDob.requestFocus();
}
if (TextUtils.isEmpty(textAdress)) {
Toast.makeText(MemberRegistration.this, "Please Enter Right Address", Toast.LENGTH_SHORT).show();
etAddress.setError("Address Required");
etAddress.requestFocus();
}
if (radioGroupGender.getCheckedRadioButtonId() == -1) {
Toast.makeText(MemberRegistration.this, "Please Select The Gender", Toast.LENGTH_SHORT).show();
etGender.setError("Address Required");
etGender.requestFocus();
}
if (TextUtils.isEmpty(textPhoneNumber)) {
Toast.makeText(MemberRegistration.this, "Please Enter The Phone Number", Toast.LENGTH_SHORT).show();
etPhoneNumber.setError("Phone Number Required");
etPhoneNumber.requestFocus();
}
if (textPhoneNumber.length() != 10) {
Toast.makeText(MemberRegistration.this, "Please Re-Enter The Phone Number", Toast.LENGTH_SHORT).show();
etPhoneNumber.setError("Phone Number Should be 10 Digits");
etPhoneNumber.requestFocus();
}
if (TextUtils.isEmpty(textAdarCard)) {
Toast.makeText(MemberRegistration.this, "Please Enter The Member Adar card Number", Toast.LENGTH_SHORT).show();
etAdarCard.setError("Member Adar card Number is Required");
etAdarCard.requestFocus();
}
else{
registerMemberUser(textName, textEmail, textDob, textGender, textAdress, textPhoneNumber, textIdCard, textPenCard, textAdarCard, textAmount, textInterest);
}
}
});
}
public void registerMemberUser(String textName, String textEmail, String textDob, String textGender, String textAdress, String textPhoneNumber, String textIdCard, String textPenCard, String textAdarCard, String textAmount, String textInterest) {
// Data connection with realtime database
firebaseDatabase = FirebaseDatabase.getInstance();
rootReference = firebaseDatabase.getReference();
memberReference = rootReference.child("Member Register Activity");
memberId = memberReference.push().getKey();
ReadWriteDetails readWriteDetails = new ReadWriteDetails(memberId, textName, textEmail, textDob, textGender, textAdress, textPhoneNumber, textIdCard, textPenCard, textAdarCard, textAmount, textInterest);
memberReference.child(memberId).setValue(readWriteDetails).addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
Toast.makeText(MemberRegistration.this, "Sucessfully Completed", Toast.LENGTH_SHORT).show();
}
});
}
}
