Nested class Null safety

A widget that simplify the writing of deeply nested widget trees.

It relies on the new kind of widget SingleChildWidget, which has two concrete implementations:

They are both respectively a SingleChildWidget variant of StatelessWidget and StatefulWidget.

The difference between a widget and its single-child variant is that they have a custom build method that takes an extra parameter.

As such, a StatelessWidget would be:

class MyWidget extends StatelessWidget {
  MyWidget({Key key, this.child}): super(key: key);

  final Widget child;

  Widget build(BuildContext context) {
    return SomethingWidget(child: child);

Whereas a SingleChildStatelessWidget would be:

class MyWidget extends SingleChildStatelessWidget {
  MyWidget({Key key, Widget child}): super(key: key, child: child);

  Widget buildWithChild(BuildContext context, Widget child) {
    return SomethingWidget(child: child);

This allows our new MyWidget to be used both with:

  child: AnotherWidget(),

and to be placed inside children of Nested like so:

  children: [
  child: AnotherWidget(),
Implemented types


Nested({Key? key, required List<SingleChildWidget> children, Widget? child})
Allows configuring key, children and child


hashCode int
The hash code for this object. [...]
@nonVirtual, read-only, inherited
key Key?
Controls how one widget replaces another widget in the tree. [...]
final, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited


build(BuildContext context) Widget
Describes the part of the user interface represented by this widget. [...]
createElement() → _NestedElement
Creates a StatelessElement to manage this widget's location in the tree. [...]
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children. [...]
@protected, inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep. [...]
toString({DiagnosticLevel minLevel =}) String
A string representation of this object. [...]
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a string representation of this node and its descendants. [...]
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a one-line detailed description of the object. [...]
toStringShort() String
A short, textual description of this widget.


operator ==(Object other) bool
The equality operator. [...]
@nonVirtual, inherited