StreamProvider<T> class

Listens to a Stream and exposes its content to child and descendants.

Its main use-case is to provide to a large number of a widget the content of a Stream, without caring about reacting to events. A typical example would be to expose the battery level, or a Firebase query.

Trying to use Stream to replace ChangeNotifier is outside of the scope of this class.

It is considered an error to pass a stream that can emit errors without providing a catchError method.

initialData determines the value exposed until the Stream emits a value.

By default, StreamProvider considers that the Stream listened uses immutable data. As such, it will not rebuild dependents if the previous and the new value are ==. To change this behavior, pass a custom updateShouldNotify.

See also:

Inheritance

Constructors

StreamProvider({Key? key, required Create<Stream<T>?> create, required T initialData, ErrorBuilder<T>? catchError, UpdateShouldNotify<T>? updateShouldNotify, bool? lazy, TransitionBuilder? builder, Widget? child})
Creates a Stream using create and subscribes to it.
StreamProvider.value({Key? key, required Stream<T>? value, required T initialData, ErrorBuilder<T>? catchError, UpdateShouldNotify<T>? updateShouldNotify, bool? lazy, TransitionBuilder? builder, Widget? child})
Listens to value and expose it to all of StreamProvider descendants.

Properties

builder TransitionBuilder?
Syntax sugar for obtaining a BuildContext that can read the provider created.
finalinherited
hashCode int
The hash code for this object.
no setterinherited
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited

Methods

build(BuildContext context) Widget
Describes the part of the user interface represented by this widget.
inherited
buildWithChild(BuildContext context, Widget? child) Widget
A build method that receives an extra child parameter.
inherited
createElement() → _InheritedProviderElement<T>
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.
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}) 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