SelectionListener class

A SelectionContainer that allows the user to access the SelectionDetails and listen to selection changes for the child subtree it wraps under a SelectionArea or SelectableRegion.

The selection updates are provided through the selectionNotifier, to listen to these updates attach a listener through SelectionListenerNotifier.addListener.

This widget does not listen to selection changes of nested SelectionAreas or SelectableRegions in its subtree because those widgets are self-contained and do not bubble up their selection. To listen to selection changes of a SelectionArea or SelectableRegion under this SelectionListener, add an additional SelectionListener under each one.

This example shows how to use SelectionListener to access the SelectionDetails under a SelectionArea or SelectableRegion.
link

To create a local project with this code sample, run:
flutter create --sample=widgets.SelectionListener.1 mysample

This example shows how to color the active selection red under a SelectionArea or SelectableRegion.
link

To create a local project with this code sample, run:
flutter create --sample=widgets.SelectionListener.2 mysample

See also:

Inheritance

Constructors

SelectionListener({Key? key, required SelectionListenerNotifier selectionNotifier, required Widget child})
Create a new SelectionListener widget.
const

Properties

child Widget
The child widget this selection listener applies to.
final
hashCode int
The hash code for this object.
no setterinherited
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
selectionNotifier SelectionListenerNotifier
Notifies listeners when the selection has changed.
final

Methods

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