SliverReorderableList class

A sliver list that allows the user to interactively reorder the list items.

It is up to the application to wrap each child (or an internal part of the child) with a drag listener that will recognize the start of an item drag and then start the reorder by calling SliverReorderableListState.startItemDragReorder. This is most easily achieved by wrapping each child in a ReorderableDragStartListener or a ReorderableDelayedDragStartListener. These will take care of recognizing the start of a drag gesture and call the list state's start item drag method.

This widget's SliverReorderableListState can be used to manually start an item reorder, or cancel a current drag that's already underway. To refer to the SliverReorderableListState either provide a GlobalKey or use the static SliverReorderableList.of method from an item's build method.

See also:

  • ReorderableList, a regular widget list that allows the user to reorder its items.
  • ReorderableListView, a Material Design list that allows the user to reorder its items.
Inheritance

Constructors

SliverReorderableList({Key? key, required IndexedWidgetBuilder itemBuilder, ChildIndexGetter? findChildIndexCallback, required int itemCount, required ReorderCallback onReorder, void onReorderStart(int)?, void onReorderEnd(int)?, double? itemExtent, ItemExtentBuilder? itemExtentBuilder, Widget? prototypeItem, ReorderItemProxyDecorator? proxyDecorator, double? autoScrollerVelocityScalar})
Creates a sliver list that allows the user to interactively reorder its items.
const

Properties

autoScrollerVelocityScalar double
The velocity scalar per pixel over scroll.
final
findChildIndexCallback ChildIndexGetter?
Called to find the new index of a child based on its key in case of reordering.
final
hashCode int
The hash code for this object.
no setterinherited
itemBuilder IndexedWidgetBuilder
Called, as needed, to build list item widgets.
final
itemCount int
The number of items in the list.
final
itemExtent double?
If non-null, forces the children to have the given extent in the scroll direction.
final
itemExtentBuilder ItemExtentBuilder?
If non-null, forces the children to have the corresponding extent returned by the builder.
final
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
onReorder ReorderCallback
A callback used by the list to report that a list item has been dragged to a new location in the list and the application should update the order of the items.
final
onReorderEnd → void Function(int)?
A callback that is called when the dragged item is dropped.
final
onReorderStart → void Function(int)?
A callback that is called when an item drag has started.
final
prototypeItem Widget?
If non-null, forces the children to have the same extent as the given widget in the scroll direction.
final
proxyDecorator ReorderItemProxyDecorator?
A callback that allows the app to add an animated decoration around an item when it is being dragged.
final
runtimeType Type
A representation of the runtime type of the object.
no setterinherited

Methods

createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() SliverReorderableListState
Creates the mutable state for this widget at a given location in the tree.
override
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) String
A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug, int wrapWidth = 65}) String
Returns a string representation of this node and its descendants.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a one-line detailed description of the object.
inherited
toStringShort() String
A short, textual description of this widget.
inherited

Operators

operator ==(Object other) bool
The equality operator.
inherited

Static Methods

maybeOf(BuildContext context) SliverReorderableListState?
The state from the closest instance of this class that encloses the given context.
of(BuildContext context) SliverReorderableListState
The state from the closest instance of this class that encloses the given context.