QueryState<T> class

Represents the current state of a query.

A QueryState contains all information about an async operation: the current data, any error that occurred, and the current status.

Use the computed properties (isLoading, hasData, hasError) to easily check the query state in your UI.

Example:

builder: (context, state) {
  if (state.isLoading) return CircularProgressIndicator();
  if (state.hasError) return Text('Error: ${state.error}');
  if (state.hasData) return Text('Data: ${state.data}');
  return SizedBox();
}
Annotations

Constructors

QueryState({required QueryStatus status, T? data, bool hasValue = false, Object? error, StackTrace? stackTrace, bool isFetching = false, DateTime? dataUpdatedAt, bool isStale = false})
Creates a query state with explicit values.
const
QueryState.error(Object error, [StackTrace? stackTrace])
Creates an error state with error and optional stackTrace.
factory
QueryState.idle()
Creates an idle state (query not started yet).
factory
QueryState.loading({T? data, bool isFetching = false, bool isStale = false})
Creates a loading state.
factory
QueryState.success(T data, {DateTime? dataUpdatedAt, bool isFetching = false, bool isStale = false, bool hasValue = true})
Creates a success state with data.
factory

Properties

data → T?
The data returned by the async operation, or null if not yet loaded.
final
dataUpdatedAt → DateTime?
When the data was last updated.
final
error → Object?
The error that occurred during the async operation, or null if no error.
final
hasData → bool
Whether data is available.
no setter
hasError → bool
Whether an error has occurred.
no setter
hashCode → int
The hash code for this object.
no setteroverride
hasValue → bool
Whether the query has produced a value (even if the value is null).
final
isFetching → bool
Whether a background refetch is in progress.
final
isIdle → bool
Whether the query is in idle state (not started).
no setter
isLoading → bool
Whether the query is currently loading.
no setter
isStale → bool
Whether the data is stale (determined by cache).
final
isSuccess → bool
Whether the query completed successfully.
no setter
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
stackTrace → StackTrace?
The stack trace associated with the error, if any.
final
status → QueryStatus
The current status of the query.
final

Methods

copyWith({T? data, bool? hasValue, Object? error, StackTrace? stackTrace, QueryStatus? status, bool? isFetching, DateTime? dataUpdatedAt, bool? isStale}) → QueryState<T>
Returns a copy of this state with selected fields replaced.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
override

Operators

operator ==(Object other) → bool
The equality operator.
override