Paged GridView
GridView with following adjustments:
- PageScrollPhysics set as default
- Better scroll performance by changing cacheExtent depending on scrollOffset to prevent itemBuild during scrolling.
An example comparing scroll preformance to GridView can be found at dartpad.dev.
:warning: Doesn't improve scrollController.animateTo performance
Installation
First, add paged_grid_view
as a dependency in your pubspec.yaml file.
Usage
import 'package:paged_grid_view/paged_grid_view.dart';
@override
Widget build(BuildContext context) {
@override
Widget build(BuildContext context) {
return PagedGridView.builder(
itemCount: 1000,
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
mainAxisExtent: MediaQuery.sizeOf(context).width / 10,
crossAxisCount: 10),
scrollDirection: Axis.horizontal,
onPageChanged: (index) {
debugPrint('changed to page $index');
},
itemBuilder: (context, index) {
return ColoredBox(
key: UniqueKey(),
color: Color(Random().nextInt(0xffffff) + 0xff000000),
);
});
}
}
Example
import 'dart:math';
import 'package:flutter/material.dart';
import 'package:paged_grid_view/paged_grid_view.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Paged GridView Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: const MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({super.key});
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
double itemsPerColumn = 50;
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('PagedGridView Demo'),
),
body: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: Row(
children: [
const Text("Axis item count:"),
Expanded(
child: Slider(
max: 100,
min: 1,
divisions: 99,
label: itemsPerColumn.round().toString(),
value: itemsPerColumn,
onChanged: (double value) {
setState(() {
itemsPerColumn = value;
});
},
),
),
],
),
),
const Padding(
padding: EdgeInsets.all(8.0),
child: Center(child: Text("GridView:")),
),
Expanded(
child: GridView.builder(
itemCount: (itemsPerColumn * itemsPerColumn * 10).round(),
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
mainAxisExtent:
MediaQuery.sizeOf(context).width / itemsPerColumn.round(),
crossAxisCount: itemsPerColumn.round()),
scrollDirection: Axis.horizontal,
physics: const PageScrollPhysics(),
itemBuilder: (context, index) {
debugPrint("gridView build item $index");
return ColoredBox(
key: UniqueKey(),
color: Color(Random().nextInt(0xffffff) + 0xff000000),
);
},
)),
const Padding(
padding: EdgeInsets.all(8.0),
child: Center(child: Text("PagedGridView:")),
),
Expanded(
child: PagedGridView.builder(
itemCount: (itemsPerColumn * itemsPerColumn * 10).round(),
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
mainAxisExtent:
MediaQuery.sizeOf(context).width / itemsPerColumn.round(),
crossAxisCount: itemsPerColumn.round()),
scrollDirection: Axis.horizontal,
onPageChanged: (index) {
debugPrint('changed to page $index');
},
itemBuilder: (context, index) {
debugPrint("pagedGridView build item $index");
return ColoredBox(
key: UniqueKey(),
color: Color(Random().nextInt(0xffffff) + 0xff000000),
);
},
)),
],
),
);
}
}