TreeView<T> class

A comprehensive tree view widget with hierarchical data display and interaction.

TreeView provides a scrollable tree interface that displays hierarchical data with support for expansion/collapse, multi-selection, keyboard navigation, and visual branch lines. It handles complex tree operations like recursive selection, range selection, and immutable state updates.

The widget supports both mouse and keyboard interaction including:

Click to select items and toggle expansion
Ctrl+Click for multi-selection
Shift+Click for range selection
Arrow keys for navigation and selection
Space bar for selection toggle
Left/Right arrows for expand/collapse

Features:

Hierarchical data display with customizable branch lines
Single and multi-selection modes with recursive selection support
Keyboard navigation and accessibility
Scrollable content with shrink wrap support
Customizable expand icons and visual styling
Immutable state management with helper methods
Focus management and scope integration

The tree uses immutable data structures where all modifications return new instances. Helper methods and extensions provide convenient operations for common tree manipulations like expanding, selecting, and filtering nodes.

Example:

TreeView<String>(
  nodes: [
    TreeItem(
      data: 'Documents',
      expanded: true,
      children: [
        TreeItem(data: 'document1.txt'),
        TreeItem(data: 'document2.txt'),
      ],
    ),
    TreeItem(data: 'Images'),
  ],
  builder: (context, item) => Text(item.data),
  onSelectionChanged: (selected, multiSelect, isSelected) {
    // Handle selection changes
  },
)

Inheritance

Available extensions

Constructors

TreeView.new({Key? key, required List<TreeNode<T>> nodes, required Widget builder(BuildContext context, TreeItem<T> node), bool shrinkWrap = false, ScrollController? controller, BranchLine? branchLine, EdgeInsetsGeometry? padding, bool? expandIcon, bool? allowMultiSelect, FocusScopeNode? focusNode, TreeNodeSelectionChanged<T>? onSelectionChanged, bool? recursiveSelection}): Creates a TreeView with hierarchical data display and interaction.
const

Properties

allowMultiSelect → bool?: Whether multiple tree nodes can be selected simultaneously.
final
asBuilder → NeverWidgetBuilder: Available on Widget, provided by the WidgetExtension extension

no setter
asSliver → Widget: Available on Widget, provided by the XWidgetArcane extension

no setter
base → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
black → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
blockQuote → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
blurIn → Widget: Available on Widget, provided by the XWidgetEffect extension

no setter
bold → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
branchLine → BranchLine?: The style of branch lines connecting tree nodes.
final
builder → Widget Function(BuildContext context, TreeItem<T> node): Builder function to create widgets for tree items.
final
centered → Widget: Available on Widget, provided by the XWidget extension

no setter
controller → ScrollController?: Optional scroll controller for the tree's scroll view.
final
ellipsis → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
expand → Widget: Available on Widget, provided by the XWidget extension

no setter
expandIcon → bool?: Whether to show expand/collapse icons for nodes with children.
final
extraBold → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
extraLight → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
firstP → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
flexible → Widget: Available on Widget, provided by the XWidget extension

no setter
focusNode → FocusScopeNode?: Optional focus scope node for keyboard navigation.
final
foreground → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
h1 → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
h2 → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
h3 → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
h4 → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
hashCode → int: The hash code for this object.
no setterinherited
ih → Widget: Available on Widget, provided by the XWidgetArcane extension

no setter
inlineCode → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
intrinsicHeight → Widget: Available on Widget, provided by the XWidget extension

no setter
intrinsicSize → Widget: Available on Widget, provided by the XWidget extension

no setter
intrinsicWidth → Widget: Available on Widget, provided by the XWidget extension

no setter
italic → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
iw → Widget: Available on Widget, provided by the XWidgetArcane extension

no setter
key → Key?: Controls how one widget replaces another widget in the tree.
finalinherited
large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
lead → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
li → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
light → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
medium → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
modify → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
mono → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
muted → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
nodes → List<TreeNode<T>>: List of tree nodes to display in the tree view.
final
normal → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
onSelectionChanged → TreeNodeSelectionChanged<T>?: Callback invoked when node selection changes.
final
p → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
padding → EdgeInsetsGeometry?: Padding around the tree view content.
final
primaryForeground → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
recursiveSelection → bool?: Whether selecting a parent node also selects its children.
final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
safeArea → Widget: Available on Widget, provided by the XWidget extension

no setter
sans → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
scrollable → Widget: Available on Widget, provided by the XWidget extension

no setter
scrollableHorizontal → Widget: Available on Widget, provided by the XWidget extension

no setter
secondaryForeground → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
semiBold → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
shrinkWrap → bool: Whether the tree view should size itself to its content.
final
singleLine → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
small → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textCenter → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textEnd → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textJustify → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textLarge → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textLeft → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textMuted → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textRight → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textSmall → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
textStart → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
thin → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
underline → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x2Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x3Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x4Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x5Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x6Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x7Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x8Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
x9Large → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
xLarge → TextModifier: Available on Widget, provided by the TextExtension extension

no setter
xSmall → TextModifier: Available on Widget, provided by the TextExtension extension

no setter

Methods

animate({Key? key, List<Effect>? effects, AnimateCallback? onInit, AnimateCallback? onPlay, AnimateCallback? onComplete, bool? autoPlay, Duration? delay, AnimationController? controller, Adapter? adapter, double? target, double? value}) → Animate: Available on Widget, provided by the AnimateWidgetExtensions extension
Wraps the target Widget in an Animate instance, and returns the instance for chaining calls. Ex. myWidget.animate() is equivalent to Animate(child: myWidget).
asSkeleton({bool enabled = true, bool leaf = false, Widget? replacement, bool unite = false, AsyncSnapshot? snapshot}) → Widget: Available on Widget, provided by the SkeletonExtension extension
Converts the widget to a skeleton with advanced configuration options.
asSkeletonSliver({bool enabled = true}) → Widget: Available on Widget, provided by the SkeletonExtension extension
Converts the widget to a skeleton suitable for sliver layouts.
ast(int ml) → Widget: Available on Widget, provided by the XAST extension
center({Key? key}) → Widget: Available on Widget, provided by the WidgetExtension extension
clip({Clip clipBehavior = Clip.hardEdge}) → Widget: Available on Widget, provided by the WidgetExtension extension
clipOval({Clip clipBehavior = Clip.antiAlias}) → Widget: Available on Widget, provided by the WidgetExtension extension
clipPath({Clip clipBehavior = Clip.antiAlias, required CustomClipper<Path> clipper}) → Widget: Available on Widget, provided by the WidgetExtension extension
clipRRect({BorderRadiusGeometry borderRadius = BorderRadius.zero, Clip clipBehavior = Clip.antiAlias}) → Widget: Available on Widget, provided by the WidgetExtension extension
constrained({double? minWidth, double? maxWidth, double? minHeight, double? maxHeight, double? width, double? height}) → Widget: Available on Widget, provided by the WidgetExtension extension
createElement() → StatefulElement: Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<TreeView<T>>: Creates the mutable state for this widget at a given location in the tree.
override
debugContainer([Color color = Colors.red]) → Widget: Available on Widget, provided by the DebugContainer extension
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
excludeSkeleton({bool exclude = true}) → Widget: Available on Widget, provided by the SkeletonExtension extension
Controls whether the widget should be preserved in skeleton mode.
expanded({int flex = 1}) → Widget: Available on Widget, provided by the WidgetExtension extension
iconDestructiveForeground() → Widget: Available on Widget, provided by the IconExtension extension
iconLarge() → Widget: Available on Widget, provided by the IconExtension extension
iconMedium() → Widget: Available on Widget, provided by the IconExtension extension
iconMutedForeground() → Widget: Available on Widget, provided by the IconExtension extension
iconPrimary() → Widget: Available on Widget, provided by the IconExtension extension
iconPrimaryForeground() → Widget: Available on Widget, provided by the IconExtension extension
iconSecondary() → Widget: Available on Widget, provided by the IconExtension extension
iconSecondaryForeground() → Widget: Available on Widget, provided by the IconExtension extension
iconSmall() → Widget: Available on Widget, provided by the IconExtension extension
iconX2Large() → Widget: Available on Widget, provided by the IconExtension extension
iconX2Small() → Widget: Available on Widget, provided by the IconExtension extension
iconX3Large() → Widget: Available on Widget, provided by the IconExtension extension
iconX3Small() → Widget: Available on Widget, provided by the IconExtension extension
iconX4Large() → Widget: Available on Widget, provided by the IconExtension extension
iconX4Small() → Widget: Available on Widget, provided by the IconExtension extension
iconXLarge() → Widget: Available on Widget, provided by the IconExtension extension
iconXSmall() → Widget: Available on Widget, provided by the IconExtension extension
ignoreSkeleton() → Widget: Available on Widget, provided by the SkeletonExtension extension
Excludes the widget from skeleton effects in its parent skeleton context.
intrinsic({double? stepWidth, double? stepHeight}) → Widget: Available on Widget, provided by the WidgetExtension extension
intrinsicHeight() → Widget: Available on Widget, provided by the WidgetExtension extension
intrinsicWidth({double? stepWidth, double? stepHeight}) → Widget: Available on Widget, provided by the WidgetExtension extension
isSliver(BuildContext context) → bool: Available on Widget, provided by the XSliverWidget extension
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
onDoublePressed(VoidCallback action, {HitTestBehavior? behavior, Set<PointerDeviceKind>? supportedDevices}) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for double press/tap gestures to this widget in Arcane UI.
onHover(void action(bool hovering)) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for hover events to this widget in Arcane UI.
onLongPressed(VoidCallback action, {HitTestBehavior? behavior, Set<PointerDeviceKind>? supportedDevices}) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for long press gestures with the primary button to this widget in Arcane UI.
onLongSecondaryPressed(VoidCallback action, {HitTestBehavior? behavior, Set<PointerDeviceKind>? supportedDevices}) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for long press gestures with the secondary button to this widget in Arcane UI.
onLongTertiaryPressed(VoidCallback action, {HitTestBehavior? behavior, Set<PointerDeviceKind>? supportedDevices}) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for long press gestures with the tertiary button to this widget in Arcane UI.
onPressed(VoidCallback action, {HitTestBehavior? behavior, Set<PointerDeviceKind>? supportedDevices}) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for primary press/tap gestures to this widget in Arcane UI.
onSecondaryPressed(VoidCallback action, {HitTestBehavior? behavior, Set<PointerDeviceKind>? supportedDevices}) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for secondary press gestures (right-click) to this widget in Arcane UI.
onTertiaryPressed(VoidCallback action, {HitTestBehavior? behavior, Set<PointerDeviceKind>? supportedDevices}) → Widget: Available on Widget, provided by the XOnGestureWidget extension
Adds a handler for tertiary press gestures (middle-click) to this widget in Arcane UI.
pad(double all) → Widget: Available on Widget, provided by the XWidget extension
padBottom(double value) → Widget: Available on Widget, provided by the XWidget extension
padBy({double? left, double? top, double? right, double? bottom, double? horizontal, double? vertical}) → Widget: Available on Widget, provided by the XWidgetArcane extension
padHorizontal(double value) → Widget: Available on Widget, provided by the XWidgetArcane extension
padLeft(double value) → Widget: Available on Widget, provided by the XWidget extension
padOnly({double left = 0, double top = 0, double right = 0, double bottom = 0}) → Widget: Available on Widget, provided by the XWidget extension
padRight(double value) → Widget: Available on Widget, provided by the XWidget extension
padSliverBy({double? left, double? top, double? right, double? bottom, double? horizontal, double? vertical}) → Widget: Available on Widget, provided by the XWidgetArcane extension
padSliverHorizontal(double value) → Widget: Available on Widget, provided by the XWidgetArcane extension
padTop(double value) → Widget: Available on Widget, provided by the XWidget extension
positioned({Key? key, double? left, double? top, double? right, double? bottom}) → Widget: Available on Widget, provided by the WidgetExtension extension
shadeEdge(double radius) → Widget: Available on Widget, provided by the XWidgetEdge extension
shadeFrost(double value) → Widget: Available on Widget, provided by the XWidgetFrost extension
shadeInvert() → Widget: Available on Widget, provided by the XWidgetInvert extension
shadePixelate(double radius) → Widget: Available on Widget, provided by the XWidgetPixelate extension
shadePixelateBlur({int samples = 4, double pixelSize = 8, double radius = 2}) → Widget: Available on Widget, provided by the XWidgetPixelateBlur extension
shadeRGB({double radius = 5, double spin = 1}) → Widget: Available on Widget, provided by the XWidgetRGB extension
shadeWarp({double amplitude = 1, double frequency = 1, double z = 1, int octaves = 2}) → Widget: Available on Widget, provided by the XWidgetWarp extension
shadeWarpAnimation({double amplitude = 1, double frequency = 1, double z = 1, double zSpeed = 1, int octaves = 2}) → Widget: Available on Widget, provided by the XWidgetWarp extension
shimmer({bool loading = true}) → Widget: Available on Widget, provided by the XWidgetArcane extension
sized({double? width, double? height}) → Widget: Available on Widget, provided by the WidgetExtension extension
sized({double? width, double? height}) → Widget: Available on Widget, provided by the XWidget extension
then(InlineSpan span) → Widget: Available on Widget, provided by the TextExtension extension
thenButton({required VoidCallback onPressed, required Widget child}) → Widget: Available on Widget, provided by the TextExtension extension
thenInlineCode(String text) → Widget: Available on Widget, provided by the TextExtension extension
thenText(String text) → Widget: Available on Widget, provided by the TextExtension extension
toBox(BuildContext context, {bool softWarn = true}) → Widget: Available on Widget, provided by the XSliverWidget extension
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode: Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toSliver(BuildContext context, {bool fillRemaining = false, bool softWarn = true}) → Widget: Available on Widget, provided by the XSliverWidget extension
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
transform({Key? key, required Matrix4 transform}) → Widget: Available on Widget, provided by the WidgetExtension extension
withAlign(AlignmentGeometry alignment) → Widget: Available on Widget, provided by the WidgetExtension extension
withMargin({double? top, double? bottom, double? left, double? right, double? horizontal, double? vertical, double? all}) → Widget: Available on Widget, provided by the WidgetExtension extension
withOpacity(double opacity) → Widget: Available on Widget, provided by the WidgetExtension extension
withPadding({double? top, double? bottom, double? left, double? right, double? horizontal, double? vertical, double? all, EdgeInsetsGeometry? padding}) → Widget: Available on Widget, provided by the WidgetExtension extension
withTooltip(String tooltip) → Widget: Available on Widget, provided by the XWidgetArcane extension

Operators

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

Static Methods

collapseAll<K>(List<TreeNode<K>> nodes) → List<TreeNode<K>>
collapseItem<K>(List<TreeNode<K>> nodes, K target) → List<TreeNode<K>>
collapseNode<K>(List<TreeNode<K>> nodes, TreeNode<K> target) → List<TreeNode<K>>
defaultItemExpandHandler<K>(List<TreeNode<K>> nodes, TreeNode<K> target, ValueChanged<List<TreeNode<K>>> onChanged) → ValueChanged<bool>
defaultSelectionHandler<K>(List<TreeNode<K>> nodes, ValueChanged<List<TreeNode<K>>> onChanged) → TreeNodeSelectionChanged<K>
deselectAll<K>(List<TreeNode<K>> nodes) → List<TreeNode<K>>
deselectItem<K>(List<TreeNode<K>> nodes, K target) → List<TreeNode<K>>
deselectItems<K>(List<TreeNode<K>> nodes, Iterable<K> deselectedItems) → List<TreeNode<K>>
deselectNode<K>(List<TreeNode<K>> nodes, TreeNode<K> target) → List<TreeNode<K>>
deselectNodes<K>(List<TreeNode<K>> nodes, Iterable<TreeNode<K>> deselectedNodes) → List<TreeNode<K>>
expandAll<K>(List<TreeNode<K>> nodes) → List<TreeNode<K>>
expandItem<K>(List<TreeNode<K>> nodes, K target) → List<TreeNode<K>>
expandNode<K>(List<TreeNode<K>> nodes, TreeNode<K> target) → List<TreeNode<K>>
getSelectedItems<K>(List<TreeNode<K>> nodes) → List<K>
getSelectedNodes<K>(List<TreeNode<K>> nodes) → List<TreeNode<K>>
replaceItem<K>(List<TreeNode<K>> nodes, K oldItem, TreeNode<K> newItem) → List<TreeNode<K>>
replaceNode<K>(List<TreeNode<K>> nodes, TreeNode<K> oldNode, TreeNode<K> newNode) → List<TreeNode<K>>
replaceNodes<K>(List<TreeNode<K>> nodes, TreeNodeUnaryOperator<K> operator) → List<TreeNode<K>>
replaceNodesWithParent<K>(List<TreeNode<K>> nodes, TreeNodeUnaryOperatorWithParent<K> operator) → List<TreeNode<K>>
selectAll<K>(List<TreeNode<K>> nodes) → List<TreeNode<K>>
selectItem<K>(List<TreeNode<K>> nodes, K target) → List<TreeNode<K>>
selectItems<K>(List<TreeNode<K>> nodes, Iterable<K> selectedItems) → List<TreeNode<K>>
selectNode<K>(List<TreeNode<K>> nodes, TreeNode<K> target) → List<TreeNode<K>>
selectNodes<K>(List<TreeNode<K>> nodes, Iterable<TreeNode<K>> selectedNodes) → List<TreeNode<K>>
setSelectedItems<K>(List<TreeNode<K>> nodes, Iterable<K> selectedItems) → List<TreeNode<K>>
setSelectedNodes<K>(List<TreeNode<K>> nodes, Iterable<TreeNode<K>> selectedNodes) → List<TreeNode<K>>
toggleSelectAll<K>(List<TreeNode<K>> nodes) → List<TreeNode<K>>
toggleSelectItem<K>(List<TreeNode<K>> nodes, K target) → List<TreeNode<K>>
toggleSelectItems<K>(List<TreeNode<K>> nodes, Iterable<K> targets) → List<TreeNode<K>>
toggleSelectNode<K>(List<TreeNode<K>> nodes, TreeNode<K> target) → List<TreeNode<K>>
toggleSelectNodes<K>(List<TreeNode<K>> nodes, Iterable<TreeNode<K>> targets) → List<TreeNode<K>>
updateRecursiveSelection<K>(List<TreeNode<K>> nodes) → List<TreeNode<K>>