widgets library

SliverOverlapAbsorberHandle class

Handle to provide to a SliverOverlapAbsorber, a SliverOverlapInjector, and an NestedScrollViewViewport, to shift overlap in a NestedScrollView.

A particular SliverOverlapAbsorberHandle can only be assigned to a single SliverOverlapAbsorber at a time. It can also be (and normally is) assigned to one or more SliverOverlapInjectors, which must be later descendants of the same NestedScrollViewViewport as the SliverOverlapAbsorber. The SliverOverlapAbsorber must be a direct descendant of the NestedScrollViewViewport, taking part in the same sliver layout. (The SliverOverlapInjector can be a descendant that takes part in a nested scroll view's sliver layout.)

Whenever the NestedScrollViewViewport is marked dirty for layout, it will cause its assigned SliverOverlapAbsorberHandle to fire notifications. It is the responsibility of the SliverOverlapInjectors (and any other clients) to mark themselves dirty when this happens, in case the geometry subsequently changes during layout.

Constructors

SliverOverlapAbsorberHandle()

Properties

layoutExtent → double: The current amount of overlap being absorbed by the SliverOverlapAbsorber. [...]
read-only
scrollExtent → double: The total scroll extent of the gap being absorbed by the SliverOverlapAbsorber. [...]
read-only
hashCode → int: The hash code for this object. [...]
read-only, inherited
hasListeners → bool: Whether any listeners are currently registered. [...]
@protected, read-only, inherited
runtimeType → Type: A representation of the runtime type of the object.
read-only, inherited

Methods

toString() → String: Returns a string representation of this object.
override
addListener(VoidCallback listener) → void: Register a closure to be called when the object changes. [...]
inherited
dispose() → void: Discards any resources used by the object. After this is called, the object is not in a usable state and should be discarded (calls to addListener and removeListener will throw after the object is disposed). [...]
@mustCallSuper, inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a non-existent method or property is accessed. [...]
inherited
notifyListeners() → void: Call all the registered listeners. [...]
@protected, inherited
removeListener(VoidCallback listener) → void: Remove a previously registered closure from the list of closures that are notified when the object changes. [...]
inherited

Operators

operator ==(dynamic other) → bool: The equality operator. [...]
inherited