ObserverUtils class

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

calcAnchorTabIndex({required ObserveModel observeModel, required List<int> tabIndexs, required int currentTabIndex}) → int

Calculate the anchor tab index.

calcPersistentHeaderExtent({GlobalKey<State<StatefulWidget>>? key, BuildContext? context, required double offset}) → double

Calculate current extent of RenderSliverPersistentHeader base on target layout offset. Such as SliverAppBar

findChildContext({required BuildContext context, required bool isTargetType(Element)}) → BuildContext?

Walks the children of this context.

findRenderObject(BuildContext? context) → RenderObject?

Safely call findRenderObject method.

findViewport(RenderObject obj) → RenderViewportBase<ContainerParentDataMixin<RenderSliver>>?

Find out the viewport

isBelowOffsetSliverInViewport({required double viewportPixels, RenderSliver? sliver}) → bool

For viewport

isBelowOffsetWidgetInSliver({required double scrollViewOffset, required Axis scrollDirection, required RenderBox targetChild, double toNextOverPercent = 1}) → bool

Determines whether the offset at the bottom of the target child widget is below the specified offset.

isDisplayingChildInSliver({required RenderBox? targetChild, required double showingChildrenMaxOffset, required double scrollViewOffset, required Axis scrollDirection, double toNextOverPercent = 1}) → bool

Determines whether the target child widget is being displayed

isDisplayingSliverInViewport({required RenderSliver? sliver, required double viewportPixels, required double viewportBottomOffset}) → bool

For viewport

isReachOffsetWidgetInSliver({required double scrollViewOffset, required Axis scrollDirection, required RenderBox targetChild, double toNextOverPercent = 1}) → bool

Determines whether the target child widget has reached the specified offset

isValidListIndex(int index) → bool

Determines whether it is a valid list index.

localToGlobal({required BuildContext context, required Offset point, BuildContext? ancestor}) → Offset?

Convert the given point from the local coordinate system for this context to the global coordinate system in logical pixels.

sliverConstraints(RenderSliver sliver) → SliverConstraints?

Safely obtain RenderSliver.constraints.