SliverViewObserver class

Inheritance

Constructors

SliverViewObserver({Key? key, required Widget child, String? tag, SliverObserverController? controller, @Deprecated('It will be removed in version 2, please use [sliverContexts] instead') List<BuildContext> sliverListContexts()?, List<BuildContext> sliverContexts()?, OnObserveAllCallback<ObserveModel>? onObserveAll, OnObserveCallback<ObserveModel>? onObserve, OnObserveViewportCallback? onObserveViewport, double leadingOffset = 0, double dynamicLeadingOffset()?, double? customOverlap(BuildContext sliverContext)?, double toNextOverPercent = 1, ScrollNotificationPredicate? scrollNotificationPredicate, List<ObserverAutoTriggerObserveType>? autoTriggerObserveTypes, ObserverTriggerOnObserveType triggerOnObserveType = ObserverTriggerOnObserveType.displayingItemsChange, ObserveModel? customHandleObserve(BuildContext context)?, ObserveModel? extendedHandleObserve(BuildContext context)?})
const

Properties

autoTriggerObserveTypes → List<ObserverAutoTriggerObserveType>?
Used to set types those can trigger observe automatically.
finalinherited
child → Widget
The subtree below this widget.
finalinherited
controller → SliverObserverController?
final
customHandleObserve → ObserveModel? Function(BuildContext)?
It allows you to customize observation logic when original logic doesn't fit your needs.
finalinherited
customOverlap → double? Function(BuildContext sliverContext)?
The callback that specifies a custom overlap corresponds to sliverContext.
final
customTargetRenderSliverType → bool Function(RenderObject?)?
Used to find the target RenderSliver.
finalinherited
dynamicLeadingOffset → double Function()?
Calculate offset dynamically If this callback is implemented, the leadingOffset property will be invalid.
finalinherited
extendedHandleObserve → ObserveModel? Function(BuildContext context)?
It's used to handle the observation logic for other types of Sliver besides RenderSliverList, RenderSliverFixedExtentList and RenderSliverGrid.
final
hashCode → int
The hash code for this object.
no setterinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
leadingOffset → double
Calculate offset.
finalinherited
onObserve → OnObserveCallback<ObserveModel>?
The callback of getting observed result for first sliver.
finalinherited
onObserveAll → OnObserveAllCallback<ObserveModel>?
The callback of getting observed result map.
finalinherited
onObserveViewport → OnObserveViewportCallback?
The callback of getting all slivers those are displayed in viewport.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
scrollNotificationPredicate → ScrollNotificationPredicate?
A predicate for ScrollNotification, used to determine whether observation can be triggered.
finalinherited
sliverContexts → List<BuildContext> Function()?
The callback of getting all sliver's buildContext.
finalinherited
sliverController → SliverObserverController?
An object that can be used to dispatch a ListViewOnceObserveNotification or GridViewOnceObserveNotification.
finalinherited
tag → String?
This is for when you have multiple nested ObserverWidget widgets and you want to get the corresponding ObserverWidgetState.
finalinherited
toNextOverPercent → double
After the internal logic figure out the first child widget, if the proportion of the size of the child widget blocked to its own size exceeds the value toNextOverPercent, the next child widget will be the first child widget.
finalinherited
triggerOnObserveType → ObserverTriggerOnObserveType
Used to set the prerequisite for triggering the onObserve callback.
finalinherited

Methods

createElement() → StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<SliverViewObserver>
Creates the mutable state for this widget at a given location in the tree.
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

Static Methods

maybeOf(BuildContext context, {String? tag}) → MixViewObserverState?
Returning the closest instance of this class that encloses the given context.
of(BuildContext context, {String? tag}) → MixViewObserverState
Returning the closest instance of this class that encloses the given context.