PlTreeSelect class

A value chosen out of a hierarchy rather than out of a list.

The gap between a PlSelect and a PlTree: the first is a flat list behind a field, the second is a hierarchy that shows what it holds but has no field to put it in. A category, a folder, a region and an org chart node are all chosen from a shape a flat list flattens away.

It is the two of them composed and almost nothing else — the trigger is the shell all the pickers wear, and what is in the popup is a PlTree with a PlTextField over it. What it adds is the arithmetic between them: which nodes a query keeps, which branches that opens, and which of the ids coming back out of the tree are answers rather than roads.

PlTreeSelect(
  items: regions,
  value: chosen,
  onValueChanged: (Set<String> next) => setState(() => chosen = next),
)
Inheritance

Constructors

PlTreeSelect({required List<PlTreeSelectNode> items, Set<String> value = const <String>{}, ValueChanged<Set<String>>? onValueChanged, bool multiple = false, bool selectableBranches = false, Set<String>? expanded, ValueChanged<Set<String>>? onExpandedChanged, bool? open, ValueChanged<bool>? onOpenChanged, Widget? placeholder, bool clearable = false, bool? closeOnSelect, bool searchable = false, String? searchLabel, String? emptyLabel, String format(List<PlTreeSelectNode> chosen)?, PlassVariant variant = PlassVariant.glass, PlassSize? size, PlassColor? color, PlassDensity? density, PlassElevation elevation = 0, Widget? label, Widget? description, Widget? error, bool? invalid, Widget? startIcon, bool fullWidth = false, bool readOnly = false, bool disabled = false, String? semanticLabel, FocusNode? focusNode, bool autofocus = false, Key? key})
Creates a tree select.
const

Properties

autofocus → bool
Takes focus as it is inserted into the tree.
final
clearable → bool
Offers the × that empties the control.
final
closeOnSelect → bool?
Closes the popup as soon as a node is chosen. Defaults to !multiple.
final
color → PlassColor?
Semantic colour role.
final
density → PlassDensity?
Horizontal padding. Never the height.
final
description → Widget?
Helper text below it.
final
disabled → bool
Unavailable.
final
elevation → int
Drop shadow depth of the trigger. 0, like a PlTextField.
final
emptyLabel → String?
What the popup says when the filter matched nothing.
final
error → Widget?
Error message below it. Its presence also turns the picker invalid.
final
expanded → Set<String>?
The ids of the branches that are open. Leave it out and the picker holds its own.
final
focusNode → FocusNode?
Drive focus from outside.
final
format → String Function(List<PlTreeSelectNode> chosen)?
How the trigger writes what is held. Defaults to the labels, comma-joined.
final
fullWidth → bool
Stretches to the width of the container.
final
hashCode → int
The hash code for this object.
no setterinherited
invalid → bool?
Forces the invalid state without a message.
final
items → List<PlTreeSelectNode>
The whole tree, as data.
final
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
label → Widget?
Label above the trigger.
final
multiple → bool
Whether more than one node may be held at once.
final
onExpandedChanged → ValueChanged<Set<String>>?
Called with the whole open set after a branch is opened or closed.
final
onOpenChanged → ValueChanged<bool>?
Called when the popup should open or close.
final
onValueChanged → ValueChanged<Set<String>>?
Called with the whole selection after a node is chosen or dropped.
final
open → bool?
Whether the popup is up. Leave it out and the picker holds its own.
final
placeholder → Widget?
Shown in the trigger while nothing is chosen.
final
readOnly → bool
The value is shown but cannot be changed, and the popup does not open.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
searchable → bool
Offers a field above the tree that filters it.
final
searchLabel → String?
The word in the filter field.
final
selectableBranches → bool
Whether a node that has children may itself be chosen.
final
semanticLabel → String?
The name a screen reader gives the trigger.
final
size → PlassSize?
Height and type scale.
final
startIcon → Widget?
The glyph before the value.
final
value → Set<String>
The ids of the chosen nodes. Controlled.
final
variant → PlassVariant
What the trigger's well is cut into.
final

Methods

createElement() → StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<PlTreeSelect>
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