LazyIndexedStackPlus class

A widget that behaves like IndexedStack but loads its children lazily.

Unlike a standard IndexedStack, which inflates all children immediately, LazyIndexedStackPlus only builds a child when it first becomes active (the index matches) or if it is included in preloadIndexes.

Once a child has been built, it is kept in the widget tree to maintain its state (e.g., scroll position, text input).

This sample shows the usage of LazyIndexedStackPlus

LazyIndexedStackPlus(
  index: 0,
  preloadIndexes: {1}, // Optional: Preload specific tabs /indexes
  placeholder: Center(child: CircularProgressIndicator()),
  children: [
    HomeTab(),
    ProfileTab(),
    SettingsTab(),
  ],
);

See also:

Inheritance

Constructors

LazyIndexedStackPlus({Key? key, int index = 0, AlignmentGeometry alignment = AlignmentDirectional.topStart, StackFit sizing = StackFit.loose, Clip clipBehavior = Clip.hardEdge, TextDirection? textDirection, Widget placeholder = const SizedBox.shrink(), Set<int> preloadIndexes = const <int>{}, List<Widget> children = const <Widget>[]})
A widget that behaves like IndexedStack but loads its children lazily.
const

Properties

alignment → AlignmentGeometry
How to align the children in the stack.
final
children → List<Widget>
The list of widgets to be displayed in the stack.
final
clipBehavior → Clip
Whether to clip the overflow of children.
final
hashCode → int
The hash code for this object.
no setterinherited
index → int
The index of the child to show.
final
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
placeholder → Widget
The widget to display for children that have not been initialized yet.
final
preloadIndexes → Set<int>
A set of indexes that should be built immediately, even if they are not the current index.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
sizing → StackFit
How to size the non-positioned children in the stack.
final
textDirection → TextDirection?
The text direction with which to resolve alignment.
final

Methods

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