PointerSpace<TKey> class

Coordinate conversion + liveness for one drag session. See library docs for the nullable-read contract.

Constructors

PointerSpace({required ScrollableState scrollable, required ReorderRenderPort<TKey> renderPort})

Properties

hashCode → int

The hash code for this object.

no setter, inherited

isLive → bool

Whether the scrollable is still mounted. Prefer consuming the nullability of sample/position over branching on this directly.

no setter

position → ScrollPosition?

The scroll position, or null when the scrollable is unmounted.

no setter

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

bindScroll(VoidCallback listener) → void

Subscribes listener to the scrollable's CURRENT position and keeps the subscription glued to it. ScrollableState swaps its ScrollPosition whenever the physics runtimeType changes (_shouldUpdatePosition, applied by _updatePosition, in scrollable.dart), so the identity is re-checked on every sample and on every syncScrollSubscription call; a listener left on the dead position would never fire again. unbindScroll detaches.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

sample(Offset globalPointer) → PointerSample?

Converts globalPointer into every coordinate the drag pipeline needs, or null when the scrollable is unmounted (or its viewport box is detached mid-teardown).

syncScrollSubscription() → void

Re-points the subscription at the live position when it has been swapped. Idempotent and allocation-free: on the no-swap path it returns after one identity compare. A null live position (unmounted scrollable) detaches without re-attaching.

toString() → String

A string representation of this object.

inherited

unbindScroll() → void

Detaches the listener installed by bindScroll, if any.

Operators

operator ==(Object other) → bool

The equality operator.

inherited