A node that represents some semantic data.
The semantics tree is maintained during the semantics phase of the pipeline (i.e., during flushSemantics), which happens after compositing. The semantics tree is then uploaded into the engine for use by assistive technology.
- Inheritance
- Object
- AbstractNode
- SemanticsNode
Constructors
- SemanticsNode({SemanticsActionHandler handler })
-
Creates a semantic node.
- SemanticsNode.root({SemanticsActionHandler handler, SemanticsOwner owner })
-
Creates a semantic node to represent the root of the semantics tree.
Properties
- childrenCount → int
-
The number of children this node has.
read-only - hasCheckedState → bool
-
Whether this node has Boolean state that can be controlled by the user.
read / write - hasChildren → bool
-
Whether this node has a non-zero number of children.
read-only - id → int
-
The unique identifier for this node.
read-only - isChecked → bool
-
If this node has Boolean state that can be controlled by the user, whether that state is on or off, corresponding to
trueandfalse, respectively.read / write - label → String
-
A textual description of this node.
read / write - mergeAllDescendantsIntoThisNode → bool
-
Whether all this node and all of its descendants should be treated as one logical entity.
read / write - owner → SemanticsOwner
-
read-only
- parent → SemanticsNode
-
read-only
- rect → Rect
-
The bounding box for this node in its coordinate system.
read / write - transform → Matrix4
-
The transform from this node's coordinate system to its parent's coordinate system.
read / write - wasAffectedByClip → bool
-
Whether rect might have been influenced by clips applied by ancestors.
read / write - attached → bool
-
Whether this node is in a tree whose root is attached to something.
read-only, inherited - depth → int
-
The depth of this node in the tree.
read-only, inherited - hashCode → int
-
Get a hash code for this object.
read-only, inherited - runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited
Operators
-
operator ==(
other) → bool -
The equality operator.
inherited
Methods
-
addAction(
SemanticsAction action) → void -
Adds the given action to the set of semantic actions.
-
addAdjustmentActions(
) → void -
Adds the SemanticsAction.increase and SemanticsAction.decrease actions.
-
addChildren(
Iterable<SemanticsNode> children) → void -
Append the given children as children of this node.
-
addHorizontalScrollingActions(
) → void -
Adds the SemanticsAction.scrollLeft and SemanticsAction.scrollRight actions.
-
addVerticalScrollingActions(
) → void -
Adds the SemanticsAction.scrollUp and SemanticsAction.scrollDown actions.
-
attach(
SemanticsOwner owner) → void -
Mark this node as attached to the given owner.
-
detach(
) → void -
Mark this node as detached.
-
finalizeChildren(
) → void -
Called during the compilation phase after all the children of this node have been compiled.
-
getSemanticsData(
) → SemanticsData -
Returns a summary of the semantics for this node.
-
redepthChildren(
) → void -
Adjust the
depthof this node's children, if any. -
reset(
) → void -
Restore this node to its default state.
-
toString(
) → String -
Returns a string representation of this object.
-
toStringDeep(
[String prefixLineOne = '', String prefixOtherLines = '' ]) → String -
Returns a string representation of this node and its descendants.
-
visitChildren(
SemanticsNodeVisitor visitor) → void -
Visits the immediate children of this node.
-
adoptChild(
AbstractNode child) → void -
Mark the given node as being a child of this node.
inherited -
dropChild(
AbstractNode child) → void -
Disconnect the given node from this node.
inherited -
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent method or property is accessed.
inherited -
redepthChild(
AbstractNode child) → void -
Adjust the depth of the given
childto be greated than this node's own depth.inherited