Pfthb

I am from PHP and MySQL background and I haven't worked with JSON based DB like Firebase.

I am looking for sample code to insert data in firebase "Realtime database". I am already done with authentication stage.

To insert some data in your Firebase Database, you have to set the reference to the node you want to insert the data to and then use setValue() method.

Suppose you want to change age of the admins node, in your database in the question.

In code it looks something like this:

DatabaseReference ref = FirebaseDatabase.getInstance().getReference().child("users").child("admins");

ref.child("age").setValue(76);

The above code will replace 42 with 76, in your admins node's age child.

Read more about this here.

Getting data from Firebase Database is a bit more work, as you have to use listeners for that. There are 3 different event listeners at your disposal, that are valueEventListener childEventListener and singleValueEventListener.

These three eventListeners have different properties and you can use them as you like.

Suppose you want to retrieve age of your admins node from your database, then you may use a code like this to help. Note ref in this code is same as in above code.

ref.addSingleValueEventListener(new ValueEventListener() 
 @Override
 public void onDataChange(DataSnapshot dataSnapshot) 

 int age = dataSnapshot.child("age").getValue(String.class);
 // this will store value of age from database to the variable age

 

@Override
public void onCancelled(DatabaseError error) 
 // Failed to read value
 Log.d("TAG:", "Couldn't read data ", error.toException());

);

Read more about this here.

Refer to this link, https://firebase.google.com/docs/database/android/start/

Write a message to the database

// Write a message to the database
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef = database.getReference("message");

myRef.setValue("Hello, World!");

Read a message from the database

// Read from the database
myRef.addValueEventListener(new ValueEventListener() 
 @Override
 public void onDataChange(DataSnapshot dataSnapshot) 
 // This method is called once with the initial value and again
 // whenever data at this location is updated.
 String value = dataSnapshot.getValue(String.class);
 Log.d(TAG, "Value is: " + value);
 

@Override
public void onCancelled(DatabaseError error) 
 // Failed to read value
 Log.w(TAG, "Failed to read value.", error.toException());

);