I have some data in Firebase and want to retrieve it. Sometimes it can be null. How do I not get an exception for it?

FetchDataMethod

private void fetchData() {
mDatabaseReference.child("UserData").child(RecieversId).addChildEventListener(new ChildEventListener() {


@Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
ImageView Image = (ImageView) findViewById(R.id.imageView);
TextView Name = (TextView) findViewById(R.id.name);
TextView Status = (TextView) findViewById(R.id.status);
TextView Email = (TextView) findViewById(R.id.email);
TextView Ph = (TextView) findViewById(R.id.ph);
TextView Quote = (TextView) findViewById(R.id.quote);
for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {

String image = postSnapshot.child("Image").getValue().toString();
String name = postSnapshot.child("Name").getValue().toString();
String status = postSnapshot.child("Status").getValue().toString();
String email = postSnapshot.child("Email").getValue().toString();
String ph = postSnapshot.child("Phone_Number").getValue().toString();
String quote = postSnapshot.child("Quote").getValue().toString();

Name.setText(name);
Status.setText(status);
Email.setText(email);
Ph.setText(ph);
Quote.setText(quote);
Image.setImageResource(Integer.parseInt(image));


}
}

@Override
public void onChildChanged(DataSnapshot dataSnapshot, String s) {
}

@Override
public void onChildRemoved(DataSnapshot dataSnapshot) {
}

@Override
public void onChildMoved(DataSnapshot dataSnapshot, String s) {
}

@Override
public void onCancelled(DatabaseError databaseError) {
throw databaseError.toException();
}
});
}


How do I use the if statement? Or is there anyway to achieve the same without an if statement?

if

if

Database structure:

https://ibb.co/fLe8gd

Code:

public void onDataChange(DataSnapshot dataSnapshot) {
ImageView Image = (ImageView) findViewById(R.id.imageView);
TextView Name = (TextView) findViewById(R.id.name);
TextView Status = (TextView) findViewById(R.id.status);
TextView Email = (TextView) findViewById(R.id.name);
TextView Ph = (TextView) findViewById(R.id.number);
TextView Quote = (TextView) findViewById(R.id.name);
for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {

if (dataSnapshot != null) {

// String image = postSnapshot.child("Image").getValue().toString();
String name = dataSnapshot.child("Name").getValue().toString();
String status = dataSnapshot.child("Status").getValue().toString();
String email = dataSnapshot.child("Email").getValue().toString();
String ph = dataSnapshot.child("Phone_Number").getValue().toString();
String quote = dataSnapshot.child("Quote").getValue().toString();
Name.setText(name);
Email.setText(email);
Status.setText(status);
Ph.setText(ph);
Quote.setText(quote);
// Image.setImageResource(Integer.parseInt(image));

}
else {
Status.setText("Status not found");
Email.setText("Email not found");
Quote.setText("Quote not found");
}

}


I tried this but this isn't working. I tried datasnapshot.exists too. I don't know what else to do.

2 Answers
2

try {

private void fetchData() { ... }

catch (Exception exception){
Log.d(TAG, "fetchData: " + exception);
}


private void fetchData() {
mDatabaseReference.child("UserData").child(RecieversId).addValueEventListener(new ValueEventListener() {

@Override
public void onDataChange(DataSnapshot dataSnapshot) {
ImageView Image = (ImageView) findViewById(R.id.imageView);
TextView Name = (TextView) findViewById(R.id.name);
TextView Status = (TextView) findViewById(R.id.status);
TextView Email = (TextView) findViewById(R.id.email);
TextView Ph = (TextView) findViewById(R.id.number);
TextView Quote = (TextView) findViewById(R.id.quote);
for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {

if (dataSnapshot!=null && dataSnapshot.hasChild("Email") && dataSnapshot.child("Email") != null) {
Email.setText(dataSnapshot.child("Email").getValue().toString());
} else {
Email.setText("Email not found");
}

if (dataSnapshot!=null && dataSnapshot.hasChild("Email") && dataSnapshot.child("Quote").getValue() != null) {
Email.setText(dataSnapshot.child("Email").getValue().toString());
} else {
Quote.setText("Quote not found");
}
{

// String image = postSnapshot.child("Image").getValue().toString();
String name = dataSnapshot.child("Name").getValue().toString();
String status = dataSnapshot.child("Status").getValue().toString();
String ph = dataSnapshot.child("Phone_Number").getValue().toString();
Name.setText(name);
Status.setText(status);
Ph.setText(ph);
// Image.setImageResource(Integer.parseInt(image));

}

}
}
@Override
public void onCancelled(DatabaseError databaseError) {

}
});

}


Finally figured out the answer!...

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