SubProvider2<T, T2, R> class
Manages a Value T and exposes it to its descendants. Allows for smart Provider-Provider dependencies.
This is a combination of a SubValue
and a Provider.
Unlike a ProxyProvider where dependencies are sideloaded, this Widget completely recreates the Value when dependencies change.
The create function recieves all Providers which this depends on. The Providers are additionally treated as keys, so create is called again, should the Providers this SubProvider depends on change.
An example of a ProxyProvider
ProxyProvider<MyModel, MyOtherModel>(
create: (_) => MyOtherModel(),
update: (_, myModel, myOtherModel) => myOtherModel
..myModel = myModel,
child: /* ... */,
);
looks like this as a SubProvider:
SubProvider<MyModel, MyOtherModel>(
create: (_, myModel) => MyOtherModel(myModel: myModel),
child: /* ... */,
);
The notable difference being, that myModel can now once again be passed through the constructor, and does not have to be sideloaded. MyOtherModel is automatically recreated whenever myModel changes.
Just like Providers, SubProviders can be used inside of a MultiProvider.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatelessWidget
- SingleChildStatelessWidget
- SingleChildSubValue<
R> - SubProvider0<
R> - SubProvider<
T, R> - SubProvider2
- Implementers
Constructors
-
SubProvider2({required SubProviderCreate2<
T, T2, R> create, SubProviderUpdate2<T, T2, R> ? update, SubValueBuilderKeys? keys, SubValueBuilderDispose<R> ? dispose, TransitionBuilder? builder, Widget? child}) - Manages a Value T and exposes it to its descendants.
Properties
- builder → TransitionBuilder?
-
Builds the child of this Widget.
finalinherited
-
create
→ SubValueBuilderCreate<
R> -
Creates the value. Called at least once and everytime keys changes.
finalinherited
-
dispose
→ SubValueBuilderDispose<
R> ? -
Disposes the value. Called before recreation and when disposing. Useful for Listeners, etc.
finalinherited
- hashCode → int
-
The hash code for this object.
no setterinherited
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- keys → SubValueBuilderKeys?
-
Used to decide when to recreate the value. If null, the value is never recreated.
finalinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
-
update
→ SubValueBuilderUpdate<
R> ? -
Updates the value. Called every build. If null, does nothing.
In the call order, this comes after recreating the value.
finalinherited
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 -
buildWithValue(
BuildContext context, R value, Widget? child) → Widget -
A build method that receives both a
value
and achild
parameter.inherited -
createElement(
) → SingleChildStatelessElement -
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