Observer class

A StatelessObserverWidget that delegate its build method to builder.

See also:

Inheritance

Constructors

Observer({Key? key, required WidgetBuilder? builder, String? name, bool? warnWhenNoObservables})
Observer.withBuiltChild({Key? key, required TransitionBuilder? builderWithChild, required Widget? child, String? name, bool? warnWhenNoObservables})
Observer which excludes the child branch from being rebuilt

Properties

builder → WidgetBuilder?
regular builder, suitable for most cases
final
builderWithChild → TransitionBuilder?
builder function with child parameter
final
child → Widget?
The child widget to pass to the builderWithChild.
final
debugConstructingStackFrame → String?
The stack frame pointing to the source that constructed this instance.
final
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
warnWhenNoObservables → bool?
Whether to warn when there is no observables in the builder function null means true
finalinherited

Methods

build(BuildContext context) → Widget
Describes the part of the user interface represented by this widget.
override
createElement() → StatelessObserverElement
Creates a StatelessElement to manage this widget's location in the tree.
inherited
createReaction(dynamic onInvalidate(), {dynamic onError(Object, Reaction)?}) → Reaction
A convenience method used for testing.
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
getContext() → ReactiveContext
The context within which its reaction should be run. It is the mainContext in most cases.
inherited
getName() → String
An identifiable name that can be overriden for debugging.
override
log(String msg) → void
Convenience method to output console messages as debugging output. Logging usually happens when some internal error needs to be surfaced to the user.
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

Static Methods

debugFindConstructingStackFrame([StackTrace? stackTrace]) → String?
Finds the first non-constructor frame in the stack trace.