Android FireBase Database

Shubham Agarwal

14 December 2016

Firebase can power your app’s backend, including data storage, user authentication, static hosting, and more. We provide these services so you can focus on creating extraordinary user experiences.

What makes the FireBase powerful.

Firebase Realtime Database: synchronized in realtime to every connected client.
Firebase Authentication: built-in functionality for authenticating users with email & password, Facebook, Twitter, GitHub, Google, and anonymous auth.
Firebase Hosting: Deploy our web app in seconds with production-grade static asset hosting. All of our content is delivered over SSL from there global CDN.

Get Started with Firebase

Create an account on firebase or login to FireBase and get the standard FireBase data URL where our data is stored.

Create a project in android studio and add dependency:

compile 'com.firebase:firebase-client-android:2.3.1'

1	compile 'com.firebase:firebase-client-android:2.3.1'

NOTE: If you are getting a build error complaining about duplicate files you can choose to exclude those files by adding the packagingOptions directive to your build.gradle file:

    android {
        ...
        packagingOptions {
            exclude 'META-INF/LICENSE'
            exclude 'META-INF/LICENSE-FIREBASE.txt'
            exclude 'META-INF/NOTICE'
        }
    }

android {

...

packagingOptions {

exclude 'META-INF/LICENSE'

exclude 'META-INF/LICENSE-FIREBASE.txt'

exclude 'META-INF/NOTICE'

}

Add Android Permissions

    <uses-permission android:name="android.permission.INTERNET" />

1	<uses-permission android:name="android.permission.INTERNET" />

Setup Firebase on Android

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Firebase.setAndroidContext(this);
        Firebase myFirebaseRef = new Firebase("https://glaring-inferno-8411.firebaseio.com/");
        ...
    }

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

Firebase.setAndroidContext(this);

Firebase myFirebaseRef = new Firebase("https://glaring-inferno-8411.firebaseio.com/");

...

}

Reading Data

Reading data from your Firebase database is accomplished by attaching an event listener and handling the resulting events. Assuming we already wrote to myFirebaseRef above, we can retrieve the message value by using the addValueEventListener method:

    myFirebaseRef.child("message").addValueEventListener(new ValueEventListener() {
      @Override
      public void onDataChange(DataSnapshot snapshot) {
        System.out.println(snapshot.getValue());  //prints "Do you have data? You'll love Firebase."
      }
      @Override public void onCancelled(FirebaseError error) { }
    });

myFirebaseRef.child("message").addValueEventListener(new ValueEventListener() {

@Override

public void onDataChange(DataSnapshot snapshot) {

System.out.println(snapshot.getValue()); //prints "Do you have data? You'll love Firebase."

}

@Override public void onCancelled(FirebaseError error) { }

});

Writing Data

Once we have a reference to your data, we can write any Boolean, Long, Double, Map<String, Object> or List object to it using setValue():

myFirebaseRef.child("message").setValue("Do you have data? You'll love Firebase.");

1	myFirebaseRef.child("message").setValue("Do you have data? You'll love Firebase.");

Stay Updated!!!

Get Started with Firebase

Add Android Permissions

Reading Data

Writing Data