UndoHistory<T> class
Provides undo/redo capabilities for a ValueNotifier.
Listens to value and saves relevant values for undoing/redoing. The cadence at which values are saved is a best approximation of the native behaviors of a number of hardware keyboard on Flutter's desktop platforms, as there are subtle differences between each of the platforms.
Listens to keyboard undo/redo shortcuts and calls onTriggered when a shortcut is triggered that would affect the state of the value.
The child must manage focus on the focusNode. For example, using a TextField or Focus widget.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- UndoHistory
Constructors
-
UndoHistory({Key? key, bool shouldChangeUndoStack(T? oldValue, T newValue)?, required ValueNotifier<
T> value, required void onTriggered(T value), required FocusNode focusNode, T undoStackModifier(T value)?, UndoHistoryController? controller, required Widget child}) -
Creates an instance of UndoHistory.
const
Properties
- child → Widget
-
The child widget of UndoHistory.
final
- controller → UndoHistoryController?
-
Controls the undo state.
final
- focusNode → FocusNode
-
The FocusNode that will be used to listen for focus to set the initial
undo state for the element.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- onTriggered → void Function(T value)
-
Called when an undo or redo causes a state change.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- shouldChangeUndoStack → bool Function(T? oldValue, T newValue)?
-
Called when checking whether a value change should be pushed onto
the undo stack.
final
- undoStackModifier → T Function(T value)?
-
Called right before a new entry is pushed to the undo stack.
final
-
value
→ ValueNotifier<
T> -
The value to track over time.
final
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → State< UndoHistory< T> > -
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