<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<receiver
        android:name=".BroadcastReceiver.NetworkStateReceiver"
        android:enabled="true"
        android:permission="android.permission.ACCESS_NETWORK_STATE"
        tools:ignore="InnerclassSeparator">
        <intent-filter>
            <category android:name="android.intent.category.DEFAULT" />

            <action android:name="android.net.conn.CONNECTIVITY_CHANGE"
                tools:ignore="BatteryLife" />
        </intent-filter>
    </receiver>

public class NetworkStateReceiver extends BroadcastReceiver {

private ConnectionFirebase connectionFirebase;

@Override
public void onReceive(Context context, Intent intent) {
    ConnectivityManager connectivityManager =
            (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
    onNetworkChange(networkInfo, context);
}

private void onNetworkChange(NetworkInfo networkInfo, Context context){
    if (connectionFirebase == null){
        connectionFirebase = new ConnectionFirebase();
    }
    if (networkInfo != null){
        if (networkInfo.getState() == NetworkInfo.State.CONNECTED
                || networkInfo.getState() == NetworkInfo.State.CONNECTING){
            connectionFirebase.saveNameWifi(context.getApplicationContext());
        }
    }
}