README.md

Firebase Pagination

A simple and effective way to Paginate Firebase related data.

---

Realtime Database	Firestore

Features

• FirestorePagination to simplify paginating firestore collections.
• RealtimeDBPagination to simplify paginating realtime database nodes.
• Get live updates when new data is added using isLive property.
• Get realtime changes on already loaded data.
• Descending pagination for RealtimeDBPagination.

Getting started

Add to Dependencies

firebase_pagination: ^3.1.0

Import the package

import 'package:firebase_pagination/firebase_pagination.dart';

Usage

Simplest Firestore Pagination

FirestorePagination(
  query: FirebaseFirestore.instance.collection('scores').orderBy('score'),
  itemBuilder: (context, documentSnapshot, index) {
    final data = documentSnapshot.data() as Map<String, dynamic>;

    // Do something cool with the data
  },
),

Simplest Firebase Realtime Database Pagination

RealtimeDBPagination(
  query: FirebaseDatabase.instance.ref().child('scores').orderByChild('score'),
  orderBy: 'score',
  itemBuilder: (context, dataSnapshot, index) {
    final data = dataSnapshot.value as Map<String, dynamic>;

    // Do something cool with the data
  },
),

For more examples, see the examples section.

How it Works

• A data listener is added to the query with the given limit.
• Every time the user scrolls to the bottom of the list, the limit is increased.
• If there are any changes for the loaded data, it will be automatically updated.
• If isLive is true, a live listener is added to fetch data before the first load. (i.e. Newly added data will be automatically loaded)
• When new data is added, the data listener will be removed and a new data listener will be added with the new limit.
• Also the live listener will be removed and a new live listener will be added.

Efficiency & Performance

• Both FirestorePagination and RealtimeDBPagination uses maximum of two stream listeners to fetch data.
• Hence it is performant and uses minimum amount of resources.
• The listeners are automatically removed when the widget is removed from the widget tree.
• For fetching data, the widgets uses this hack to minimize the number of reads from the database.

Description

Property	Description	Type	Default
query	The query to use to fetch data from Firestore / Realtime Database.	Query	-
itemBuilder	The builder to use to build the items in the list.	Function	-
separatorBuilder	The builder to use to render the separator.	Function	separatorBuilder (package fn)
limit	The number of items to fetch from Database at once.	int	10
viewType	The type of view to use for the list.	ViewType	ViewType.list
isLive	Whether to fetch newly added items as they are added to Database.	bool	false
gridDelegate	The delegate to use for the GridView.	SliverGridDelegate	crossAxisCount: 2
wrapOptions	The Wrap widget properties to use.	WrapOptions	WrapOptions()
onEmpty	The widget to use when data is empty.	Widget	EmptyScreen()
bottomLoader	The widget to use when more data is loading.	Widget	BottomLoader()
initialLoader	The widget to use when data is loading initially.	Widget	InitialLoader()
scrollDirection	The scrolling direction of the ScrollView.	Axis	false
reverse	Whether the ScrollView scrolls in the reading direction.	bool	false
shrinkWrap	Should the ScrollView be shrink-wrapped.	bool	false
physics	The scroll behavior to use for the ScrollView.	ScrollPhysics	-
padding	The padding to use for the ScrollView.	EdgeInsetsGeometry	-
controller	The controller to use for the ScrollView.	ScrollController	-
descending	Whether the data should be fetched in descending order or not. Only works for RealtimeDBPagination	bool	false

If you liked the package, then please give it a Like 👍🏼 and Star ⭐