PatilShreyas

public class Needs {

    public Food mFood;
    public Clothes mClothes;
    public Shelter mShelter;

    @Inject
    public Needs(Food food, Clothes clothes, Shelter shelter) {
        this.mFood = food;
        this.mClothes = clothes;

PatilShreyas

public class Clothes {

    public Money mMoney;

    @Inject
    public Clothes(Money money) {
        this.mMoney = money;

        if (mMoney != null) {
            System.out.println("I've Clothes to wear!");

PatilShreyas

@Singleton
public class Money {

    public Job mJob;

    @Inject
    public Money(Job job) {
        this.mJob = job;

        if (mJob != null) {

PatilShreyas

public class Job {

    public Education mEducation;

    @Inject
    public Job(Education education) {
        this.mEducation = education;

        if (mEducation != null) {
            System.out.println("I've Job!");

PatilShreyas

package life;

import javax.inject.Inject;

public class Education {

    @Inject
    public Education() {
        System.out.println("I'm Well Educated!");
    }

PatilShreyas

package life;

import javax.inject.Inject;

public class Life {

    public Needs mNeeds;

    @Inject
    public Life(Needs needs) {

PatilShreyas

public class WithoutDI {
    public static void main(String[] args) {
        Education education = new Education();

        Job job = new Job(education);

        Money money = new Money(job);

        Food food = new Food(money);
        Clothes clothes = new Clothes(money);

PatilShreyas

dependencies {
    // Firebase SDKs
    implementation 'com.google.firebase:firebase-firestore:21.4.1'
    implementation 'com.google.firebase:firebase-database:19.2.1'

    // FirebaseUI for Real-time database
    implementation 'com.firebaseui:firebase-ui-database:6.2.0'

    // FirebaseUI for Cloud Firestore
    implementation 'com.firebaseui:firebase-ui-firestore:6.2.0'

PatilShreyas

    fun changeQuery() {
        val newQuery = mCollectionReference
            .orderBy("timestamp")
            .whereEqualTo("seen", false)
            .limitToLast(100)

        // Make new options
        val newOptions = FirestoreRecyclerOptions.Builder<Post>()
            .setQuery(newQuery, Post::class.java)

PatilShreyas

    fun changeQuery() {
        val newQuery = mBaseQuery
            .orderByChild("timestamp")
            .limitToLast(100)

        // Make new options
        val newOptions = FirebaseRecyclerOptions.Builder<Post>()
            .setQuery(newQuery, Post::class.java)
            .build()