FocusOrder class Null safety
Base class for all sort orders for OrderedTraversalPolicy traversal.
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:
- FocusTraversalGroup, a widget that groups together and imposes a traversal policy on the Focus nodes below it in the widget hierarchy.
- FocusTraversalOrder, a widget that assigns an order to a widget subtree for the OrderedTraversalPolicy to use.
- NumericFocusOrder, for a focus order that describes its order with a
double. - LexicalFocusOrder, a focus order that assigns a string-based lexical traversal order to a FocusTraversalOrder widget.
- Implemented types
- Mixed in types
- Implementers
- Annotations
Constructors
- FocusOrder()
-
Abstract const constructor. This constructor enables subclasses to provide
const constructors so that they can be used in const expressions.
const
Properties
- hashCode → int
-
The hash code for this object.
read-onlyinherited
- 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">@nonVirtualoverride
-
debugFillProperties(
DiagnosticPropertiesBuilder properties) → void - Add additional properties associated with the node.
-
doCompare(
covariant FocusOrder other) → int -
The subclass implementation called by compareTo to compare orders.
protected">@protected
-
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