ListViewObserver class
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- ListViewObserver
Constructors
-
ListViewObserver.new({Key? key, required Widget child, String? tag, ListObserverController? controller, List<
BuildContext> sliverListContexts()?, OnObserveAllCallback<ListViewObserveModel> ? onObserveAll, OnObserveCallback<ListViewObserveModel> ? onObserve, double leadingOffset = 0, double dynamicLeadingOffset()?, double toNextOverPercent = 1, ScrollNotificationPredicate? scrollNotificationPredicate, List<ObserverAutoTriggerObserveType> ? autoTriggerObserveTypes, ObserverTriggerOnObserveType triggerOnObserveType = ObserverTriggerOnObserveType.displayingItemsChange, ListViewObserveModel? customHandleObserve(BuildContext context)?, bool customTargetRenderSliverType(RenderObject?)?}) -
const
Properties
-
autoTriggerObserveTypes
→ List<
ObserverAutoTriggerObserveType> ? -
Used to set types those can trigger observe automatically.
finalinherited
- child → Widget
-
The subtree below this widget.
finalinherited
- controller → ListObserverController?
-
final
- customHandleObserve → ListViewObserveModel? Function(BuildContext)?
-
It allows you to customize observation logic when original logic doesn't
fit your needs.
finalinherited
- 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 - 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<
ListViewObserveModel> ? -
The callback of getting observed result for first sliver.
finalinherited
-
onObserveAll
→ OnObserveAllCallback<
ListViewObserveModel> ? -
The callback of getting observed result map.
finalinherited
- 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 → ListObserverController?
-
An object that can be used to dispatch a ListViewOnceObserveNotification
or GridViewOnceObserveNotification.
finalinherited
-
sliverListContexts
→ List<
BuildContext> Function()? -
The callback of getting all sliverList's buildContext.
final
- tag → String?
-
This is for when you have multiple nested
ObserverWidget
widgets and you want to get the correspondingObserverWidgetState
.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< ListViewObserver> - 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
-
isSupportRenderSliverType(
RenderObject? obj) → bool -
Determine whether the
obj
is a supported RenderSliver type. -
maybeOf(
BuildContext context, {String? tag}) → ListViewObserverState? - Returning the closest instance of this class that encloses the given context.
-
of(
BuildContext context, {String? tag}) → ListViewObserverState - Returning the closest instance of this class that encloses the given context.