StateView class

Picks what to render based on the current ViewState, and cross-fades between states as it changes.

Instead of scattering if (loading) ... else if (error) ... across your build methods, describe each case once and switch on a single value:

StateView(
  state: state,
  loading: const LoadingState(),
  empty: const EmptyState(title: 'No products found'),
  error: ErrorState(onAction: _retry),
  noInternet: NoInternetState(onRetry: _retry),
  child: ProductList(products: products),
)

Any slot you leave out falls back to a sensible default, so you only fill in the ones you want to customise. Pass onRetry and the default error and no-internet states come pre-wired with a working retry button:

StateView(state: state, onRetry: _load, child: ProductList(...))
Inheritance

Constructors

StateView({Key? key, required ViewState state, Widget? child, Widget? loading, Widget? empty, Widget? error, Widget? noInternet, FutureOr<void> onRetry()?, bool animate = true, Duration duration = const Duration(milliseconds: 300), AnimatedSwitcherTransitionBuilder? transitionBuilder})
const

Properties

animate → bool
Whether to cross-fade when state changes. Defaults to true, and is skipped automatically when the OS "reduce motion" setting is on.
final
child → Widget?
Shown for ViewState.content — your actual screen.
final
duration → Duration
Duration of the cross-fade between states.
final
empty → Widget?
Shown for ViewState.empty. Defaults to an EmptyState.
final
error → Widget?
Shown for ViewState.error. Defaults to an ErrorState.
final
hashCode → int
The hash code for this object.
no setterinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
loading → Widget?
Shown for ViewState.loading. Defaults to a LoadingState.
final
noInternet → Widget?
Shown for ViewState.noInternet. Defaults to a NoInternetState.
final
onRetry → FutureOr<void> Function()?
Wires the retry button of the default error and noInternet widgets, so the common case needs no explicit ErrorState at all. Ignored for slots you've filled in yourself. Returning a Future shows inline progress on the button until it completes.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
state → ViewState
Which state to show right now.
final
transitionBuilder → AnimatedSwitcherTransitionBuilder?
Customises the transition between states — same contract as AnimatedSwitcher.transitionBuilder. Defaults to a cross-fade.
final

Methods

build(BuildContext context) → Widget
Describes the part of the user interface represented by this widget.
override
createElement() → StatelessElement
Creates a StatelessElement to manage this widget's location in the tree.
inherited
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.
override
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