sticky_infinite_list 1.0.1+hotfix.1 sticky_infinite_list: ^1.0.1+hotfix.1 copied to clipboard
Infinite list with sticky headers that can be rendered in both directions. Can be customized or with config options or with override
Sticky Infinite List #
Infinite list with sticky headers.
This package was made in order to make possible render infinite list in both directions with sticky headers, unlike most packages in Dart Pub.
It highly customizable and doesn't have any third party dependencies or native(Android/iOS) code.
In addition to default usage, this package exposes some classes, that
can be overridden if needed. Also some classes it can be used inside
Scrollable widgets independently from InfiniteList
container.
This package uses CustomScrollView
to perform scroll with all
benefits for performance that Flutter provides.
Demo #
Getting Started #
Install package and import
import 'package:sticky_infinite_list/sticky_infinite_list.dart';
Package exposes InfiniteList
, InfiniteListItem
, StickyListItem
,
StickyListItemRenderObject
classes
Examples #
Simple example #
To start using Infinite list with sticky headers,
you need to create instance InfiniteList
with builder specified.
No need to specify any additional config to make it work
import 'package:sticky_infinite_list/sticky_infinite_list.dart';
class Example extends StatelessWidget {
@override
Widget build(BuildContext context) {
return InfiniteList(
builder: (BuildContext context, int index) {
/// Builder requires [InfiniteList] to be returned
return InfiniteListItem(
/// Header builder
headerBuilder: (BuildContext context) {
return Container(
///...
);
},
/// Content builder
contentBuilder: (BuildContext context) {
return Container(
///...
);
},
);
}
);
}
}
Extended configuration #
Available configuration
Alongside with minimal config to start using.
InfiniteList
allows you to define config for scroll list rendering
InfiniteList(
/// Optional parameter to pass ScrollController instance
controller: ScrollController(),
/// Optional parameter
/// to specify scroll direction
///
/// By default scroll will be rendered with just positive
/// direction `InfiniteListDirection.forward`
///
/// If you need infinite list in both directions use `InfiniteListDirection.multi`
direction: InfiniteListDirection.multi,
/// Min child count.
///
/// Will be used only when `direction: InfiniteListDirection.multi`
///
/// Accepts negative values only
minChildCount: -100,
/// Max child count
///
/// Specifies number of elements for forward list
maxChildCount: 100,
/// Item builder
///
/// Should return `InfiniteListItem`
builder: (BuildContext context, int index) {
return InfiniteListItem(
//...
)
}
)
InfiniteListItem
allows you to specify more options for you customization.
InfiniteListItem(
/// Simple Header builder
/// that will be called once during List item render
headerBuilder: (BuildContext context) {},
/// Header builder, that will be invoked each time
/// when header should change it's position
///
/// Unlike prev method, it also provides `state` of header
/// position
///
/// This callback has higher priority than [headerBuilder],
/// so if both header builders will be provided,
/// [headerBuilder] will be ignored
headerStateBuilder: (BuildContext context, StickyState<int> state) {},
/// Content builder
contentBuilder: (BuildContext context) {},
/// Min offset invoker
///
/// This callback is called on each header position change,
/// to define when header should be stick to the bottom of
/// content.
///
/// If this method not provided or it returns `0`,
/// header will be in sticky state until list item
/// will be visible inside view port
minOffsetProvider: (StickyState<int> state) {},
);
For more info take a look at Example project
Available for override #
In most cases it will be enough to just use InfiniteListItem
But in some cases you may need to add additional functionality to each item.
Luckily you can extend and override base InfiniteListItem
class
/// Generic `I` is index type, by default list item uses `int`
class SomeCustomListItem extends InfiniteListItem<I> {
/// Let item builder know if it should watch
/// header position changes
///
/// If this value is `true` - it will invoke [buildHeader]
/// each time header position changes
@override
bool get watchStickyState => true;
/// Let item builder know that this class
/// provides header
///
/// If it returns `false` - [buildHeader] will be ignored
/// and never called
@override
bool get hasStickyHeader => true;
/// This methods builds header
///
/// If [watchStickyState] is `true`,
/// it will be invoked on each header position change
/// and `state` option will be provided
///
/// Otherwise it will be called only once on initial render
/// and each header position change won't invoke this method.
///
/// Also in that case `state` will be `null`
@override
Widget buildHeader(BuildContext context, [StickyState<I> state]) {}
/// Content item builder
///
/// This method invoked only once
@override
Widget buildContent(BuildContext context) => {}
/// Called during init state (see Statefull widget [State.initState])
///
/// For additional information about Statefull widget `initState`
/// lifecycle - see Flutter docs
@protected
@mustCallSuper
void initState() {}
/// Called during item dispose (see Statefull widget [State.dispose])
///
/// For additional information about Statefull widget `dispose`
/// lifecycle - see Flutter docs
@protected
@mustCallSuper
void dispose() {}
}
Need more override?.. Ok (not tested)
If you get any problems with this type of override, please create an issue
Alongside with list item override, to use inside InfiniteList
builder,
you can also use StickyListItem
, that exposed by this package too, independently.
This class uses Stream
to inform it's parent about header position changes
Also it requires to be rendered inside Scrollable
widget and Viewport
,
since it subscribes to scroll event and calculates position
against Viewport
coordinates (see StickyListItemRenderObject
class
for more information)
Changelog #
Please see the Changelog page to know what's recently changed.
Bugs/Requests #
If you encounter any problems feel free to open an issue. If you feel the library is missing a feature, please raise a ticket on Github and I'll look into it. Pull request are also welcome.
Known issues #
Currently this package can't work with reverse lists. I hope I will get enough time to implement this feature soon)