SliverAnimatedTree<T extends Object> class
A wrapper around SliverList that adds tree viewing capabilities with support for automatic expand and collapse animations.
Usage:
@override
Widget build(BuildContext context) {
return CustomScrollView(
slivers: [
SliverAnimatedTree<Node>(
controller: treeController,
duration: const Duration(milliseconds, 300),
curve: Curves.linear,
maxNodesToShowWhenAnimating: 50,
nodeBuilder: (BuildContext context, TreeEntry<Node> entry) {
...
},
),
],
);
}
This widget will listen to controller and rebuild the inner flat representation of the tree keeping a map of the expansion state of tree nodes to then check if the cached value is different from the current node expansion state when visiting that node during flattening and will mark it to be animated. When a node is marked to animate, its subtree won't be traversed during flattening to later on be rendered in the same list item of the subtree root's node widget. Once the animation completes, the node is removed from the set of animating nodes and the tree is flattened again so the animating subtree can go back to being one list item per node.
See also:
- AnimatedTreeView, which covers the CustomScrollView boilerplate.
- SliverTree, a tree sliver with no custom behaviors.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- SliverTree<
T> - SliverAnimatedTree
Constructors
-
SliverAnimatedTree({Key? key, required TreeController<
T> controller, required TreeNodeBuilder<T> nodeBuilder, TreeTransitionBuilder transitionBuilder = defaultTreeTransitionBuilder, Duration duration = const Duration(milliseconds: 300), Curve curve = Curves.linear, int maxNodesToShowWhenAnimating = 50}) -
Creates a SliverAnimatedTree.
const
Properties
-
controller
→ TreeController<
T> -
The object responsible for providing access to tree nodes and its states.
finalinherited
- curve → Curve
-
The default curve to use when animating the expand/collapse operations.
final
- duration → Duration
-
The default duration to use when animating the expand/collapse operations.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- maxNodesToShowWhenAnimating → int
-
The amount of nodes that are going to be shown on an animating subtree.
final
-
nodeBuilder
→ TreeNodeBuilder<
T> -
Callback used to map tree nodes into widgets.
finalinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- transitionBuilder → TreeTransitionBuilder
-
A widget builder used to apply a transition to the expansion state changes
of a node subtree when animations are enabled.
final
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → State< SliverAnimatedTree< T> > -
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}) → 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