SplitterController class Controller

A controller for a ResizableSplitter's position.

Holds the requested SplitterPosition (a fraction or a pixel pin) and exposes simple APIs to update or animate it; read effectiveFraction for the on-screen ratio after constraints are applied. A global pointer router prevents "stuck drags" when platform views steal pointer events. The router attaches only when a WidgetsBinding is available, so controllers created in pure Dart tests or before runApp stay functional - the enhanced drag cleanup simply activates once Flutter is initialized.

Inheritance

Mixed-in types

Diagnosticable

Constructors

SplitterController({SplitterPosition initialPosition = const SplitterPosition.fraction(0.5)}): Creates a splitter controller at initialPosition (default: centered).

Properties

collapsedPane → SplitterPane?: Which pane, if any, is currently collapsed; null when neither is.
no setter
debugOwner → Object?: Exposes the widget currently owning this controller in debug/test builds.
no setter
effectiveFraction → double: The on-screen start fraction, in [0, 1]. Once laid out this is the resolved layout's fraction; before the first layout, while detached, or in the brief window after a request change before the next solve, it derives from the request - resolved against the last known extent, so a pixel pin still estimates sensibly (0 before any layout). For change notifications, listen to layoutListenable.
no setter
hashCode → int: The hash code for this object.
no setterinherited
hasListeners → bool: Whether any listeners are currently registered.
no setterinherited
isAttached → bool: Whether this controller is currently attached to a ResizableSplitter.
no setter
isCollapsed → bool: Whether either pane is currently collapsed.
no setter
isDragging → bool: A convenience getter for _isDragging as a boolean.
no setter
isDraggingListenable → ValueListenable<bool>: Emits true while the user is dragging the handle.
no setter
layout → SplitterLayout?: The resolved, on-screen layout the attached splitter last published, or null before the first layout (or while detached from any view).
no setter
layoutListenable → ValueListenable<SplitterLayout?>: Notifies whenever the resolved layout changes. This is a separate observable from the request notifier (value); listen here to track the on-screen geometry rather than the intent.
no setter
position → SplitterPosition: The requested position (a fraction or pixel pin); shorthand for value.position.
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
value ↔ SplitterState: The current value stored in this notifier.
getter/setter pairinherited-getteroverride-setter

Methods

addListener(VoidCallback listener) → void: Register a closure to be called when the object changes.
inherited
animateTo(double target, {Duration duration = const Duration(milliseconds: 200), Curve curve = Curves.easeOutCubic}) → Future<SplitterAnimationStatus>: Animates the split ratio to target, resolving with a SplitterAnimationStatus that reports how the run ended.
collapse(SplitterPane pane) → void: Collapses pane to its SplitterPaneConstraints.collapsedExtent, bypassing that pane's minimum. The position in value is left untouched, so expand restores the prior position. Collapsing the already-collapsed pane is a no-op; collapsing the other pane just moves the collapse across.
debugFillProperties(DiagnosticPropertiesBuilder properties) → void: Add additional properties associated with the node.
override
dispose() → void: Discards any resources used by the object.
override
expand() → void: Expands a collapsed pane, restoring the position held before it collapsed (the untouched position). A no-op when neither pane is collapsed.
jumpTo(SplitterPosition position) → void: Requests position as a fresh intent: clears any collapse and supersedes a running animation. The on-screen result is still clamped by the solver.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
notifyListeners() → void: Call all the registered listeners.
inherited
removeListener(VoidCallback listener) → void: Remove a previously registered closure from the list of closures that are notified when the object changes.
inherited
reset([double to = 0.5]) → void: Resets the splitter to a fractional position, defaulting to center.
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode: Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toggleCollapse(SplitterPane pane) → void: Collapses pane if it is not already collapsed, otherwise expands.
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
updateRatio(double newRatio, {double threshold = 0.002}) → void: Updates to a fractional position, with an optional threshold to prevent chatty updates. The threshold is compared against effectiveFraction.

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Static Methods

resetGlobalRouter() → void: Resets the global pointer router. For testing only.