LexicalFocusOrder class Null safety
Can be given to a FocusTraversalOrder widget to use a String to assign a lexical order to a widget subtree that is using a OrderedTraversalPolicy to define the order in which widgets should be traversed with the keyboard.
This sorts strings using Dart's default string comparison, which is not locale-specific.
Only orders of the same type are comparable. If a set of widgets in the same FocusTraversalGroup contains orders that are not comparable with each other, it will assert, since the ordering between such keys is undefined. To avoid collisions, use a FocusTraversalGroup to group similarly ordered widgets together.
When overriding, FocusOrder.doCompare must be overridden instead of FocusOrder.compareTo, which calls FocusOrder.doCompare to do the actual comparison.
See also:
- FocusTraversalOrder, a widget that assigns an order to a widget subtree for the OrderedTraversalPolicy to use.
- Inheritance
-
- Object
- FocusOrder
- LexicalFocusOrder
Constructors
- LexicalFocusOrder(String order)
-
Creates an object that describes a focus traversal order lexically.
const
Properties
- hashCode → int
-
The hash code for this object.
read-onlyinherited
- order → String
-
The String that defines the lexical order to assign to the widget subtree
using FocusTraversalOrder.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
read-onlyinherited
Methods
-
compareTo(
FocusOrder other) → int -
Compares this object to another Comparable.
nonVirtual">@nonVirtualinherited
-
debugFillProperties(
DiagnosticPropertiesBuilder properties) → void -
Add additional properties associated with the node.
override
-
doCompare(
covariant LexicalFocusOrder other) → int -
The subclass implementation called by compareTo to compare orders.
override
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent 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
-
toStringShort(
) → String -
A brief description of this object, usually just the runtimeType and the
hashCode.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited