DocumentSelection class

A selection within a Document.

A DocumentSelection spans from a base position to an extent position, and includes all content in between.

base and extent are instances of DocumentPosition, which represents a single position within a Document.

A DocumentSelection does not hold a reference to a Document, it only represents a directional selection within a Document. The base and extent positions must be interpreted within the context of a specific Document to locate nodes between base and extent, and to identify partial content that is selected within the base and extent nodes within the document.

Inheritance

Constructors

DocumentSelection({required DocumentPosition base, required DocumentPosition extent})
Creates a selection from the base position to the extent position within the document.
const
DocumentSelection.collapsed({required DocumentPosition position})
Creates a collapsed selection at the given position within the document.
const

Properties

base → DocumentPosition
The base position of the selection within the document.
final
end → DocumentPosition
The bounding position of the other side of a DocumentRange.
finalinherited
extent → DocumentPosition
The extent position of the selection within the document.
final
hashCode → int
The hash code for this object.
no setteroverride
isCollapsed → bool
Returns true if this selection is collapsed, or false if this selection is expanded.
no setteroverride
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
start → DocumentPosition
The bounding position of one side of a DocumentRange.
finalinherited

Methods

calculateAffinity(Document document) → TextAffinity
Returns the affinity (direction) for this selection - downstream refers to a selection that starts at earlier content and ends at later content, upstream refers to a selection that starts at later content and ends at earlier content.
collapse() → DocumentSelection
Returns a version of this that is collapsed at the extent position.
collapseDownstream(Document document) → DocumentSelection
Returns a version of this DocumentSelection that is collapsed in the downstream (end) direction.
collapseUpstream(Document document) → DocumentSelection
Returns a version of this DocumentSelection that is collapsed in the upstream (start) direction.
containsPosition(Document document, DocumentPosition position) → bool
Returns true if the given position sits within this DocumentSelection.
copyWith({DocumentPosition? base, DocumentPosition? extent}) → DocumentSelection
Creates a new DocumentSelection based on the current selection, with the provided parameters overridden.
expandTo(DocumentPosition newExtent) → DocumentSelection
Creates a copy of this selection but with the extent expanded to the given new extent.
hasDownstreamAffinity(Document document) → bool
Returns true if this selection has an affinity of TextAffinity.downstream.
hasUpstreamAffinity(Document document) → bool
Returns true if this selection has an affinity of TextAffinity.upstream.
isNormalized(Document document) → bool
Returns true if start appears at, or before end, or false otherwise.
inherited
normalize(Document document) → DocumentRange
Returns a version of this DocumentRange that's normalized.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
override

Operators

operator ==(Object other) → bool
The equality operator.
override