What is an InheritedWidget in flutter?

In Flutter, an InheritedWidget is a widget that holds a value that can be inherited by its descendants in the widget tree. It allows you to pass data down the widget tree to descendant widgets without having to pass the data explicitly through each level of the tree.

Here is an example of how you might use an InheritedWidget to pass a value down the widget tree:

class MyInheritedWidget extends InheritedWidget {
  final int data;

  MyInheritedWidget({
    Key key,
    this.data,
    Widget child,
  }) : super(key: key, child: child);

  static MyInheritedWidget of(BuildContext context) {
    return context.dependOnInheritedWidgetOfExactType<MyInheritedWidget>();
  }

  @override
  bool updateShouldNotify(MyInheritedWidget oldWidget) {
    return oldWidget.data != data;
  }
}

In this example, we have created an InheritedWidget called MyInheritedWidget that holds an integer value called data. The MyInheritedWidget.of method is used to retrieve the nearest ancestor MyInheritedWidget in the widget tree.

To pass the data value down the widget tree, we can wrap our widgets in an instance of MyInheritedWidget:

MyInheritedWidget(
  data: 42,
  child: Column(
    children: [
      MyWidget(),
      MyOtherWidget(),
    ],
  ),
)

Then, in MyWidget and MyOtherWidget, we can use the MyInheritedWidget.of method to access the data value:

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final data = MyInheritedWidget.of(context).data;
    // Use the data value in the widget's build method...
  }
}

class MyOtherWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final data = MyInheritedWidget.of(context).data;
    // Use the data value in the widget's build method...
  }
}

InheritedWidgets are a useful way to share data between widgets in a Flutter app. They can help you avoid the need to pass data explicitly through multiple levels of the widget tree, which can make your code easier to read and maintain.

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