title: Firebase Database onChildChanged() not triggered after 1st update
body: <p>I added data in Firebase Realtime Database and set <code>addChildEventListener</code> using below code.</p>
  
  <pre><code>private DatabaseReference mFirebaseDatabaseRef;
  
  mFirebaseDatabaseRef = FirebaseDatabase.getInstance().getReference("user").child("details");
  for (int i = 0; i &lt; result.size(); i++) {
                  String id = mFirebaseDatabaseRef.push().getKey();
  
                  String name = result.get(i).getName();
  
                  Details details = new Details();
                  appDetails.setName(name);
                  appDetails.setLabel(result.get(i).getLabel());
                  appDetails.setIconbase64(result.get(i).getIconbase64());
                  mFirebaseDatabaseRef.child(id).setValue(details );
              }
  addEventListener();
  </code></pre>
  
  <p>Add Child event listener method.</p>
  
  <pre><code>private void addEventListener() {
  
      mFirebaseDatabaseRef.addChildEventListener(new ChildEventListener() {
          @Override
          public void onChildAdded(@NonNull DataSnapshot dataSnapshot, @Nullable String s) {
              Log.d("Realtime", "s");
          }
  
          @Override
          public void onChildChanged(@NonNull DataSnapshot dataSnapshot, @Nullable String s) {
              Log.d("Realtime", "s");
              Toast.makeText(mContext, "Child Changed", Toast.LENGTH_LONG).show();
          }
  
          @Override
          public void onChildRemoved(@NonNull DataSnapshot dataSnapshot) {
              Log.d("Realtime", "s");
          }
  
          @Override
          public void onChildMoved(@NonNull DataSnapshot dataSnapshot, @Nullable String s) {
              Log.d("Realtime", "s");
          }
  
          @Override
          public void onCancelled(@NonNull DatabaseError databaseError) {
              Log.d("Realtime", "s");
          }
      });
  }
  </code></pre>
  
  <p>Now when I change data in Database, <code>onChildChanged</code> of <code>addChildEventListener</code> is called only for 1st time. but when I again change data in Datbase, no <code>onChildChanged</code> triggered.</p>
  
  <blockquote>
    <p>I want to trigger onChildChanged every time when I update Data in
    Datbase.</p>
  </blockquote>