LoaderBuilder class Null safety

A Widget that replace its content with different widgets depends on the state of the loader.

{@tool snippet}

Example of simple LoaderBuilder:

Widget build(BuildContext context) {
  return Scaffold(
    appBar: AppBar(title: const Text('Flutter Loader Demo')),
    body: LoaderBuilder(
      loader: () => Future.delayed(Duration(seconds: 3), () => 'Hello World'),
      builder: (context, controller, child) {
        switch(controller.state) {
          case LoaderState.error:
            return ElevatedButton(
              child: 'Error: ${controller.error}.\n\nClick here to try again',
              onPressed: () => controller.load(),
            );
          case LoaderState.loaded:
            return Text('Loaded: ${controller.data}')
          case LoaderState.init:
          case LoaderState.loading:
          default:
            return CircularProgressIndicator();
        }
      }
    ),
  );
}

{@end-tool}

Inheritance

Constructors

LoaderBuilder({Key? key, required FutureProvider loader, required LoaderWidgetBuilder builder, Widget? child, bool autoLoad = true})

Properties

autoLoad bool
Whether the loader will load the data automatically in the beginning
final
builder LoaderWidgetBuilder
Builds UI with the given LoaderController context.
final
child Widget?
The child widget which will be used by builder for caching purpose.
final
hashCode int
The hash code for this object.
@nonVirtualread-onlyinherited
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
loader FutureProvider
Provides a Future which will do the actual work for loading data.
final
runtimeType Type
A representation of the runtime type of the object.
read-onlyinherited

Methods

createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → _LoaderBuilderState
Creates the mutable state for this widget at a given location in the tree.
override
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
@protectedinherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent 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.
@nonVirtualinherited