31.30 Flutter Class Widget

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Almost everything in Flutter is a Widget. Visible widgets are the presentation elements we see in the app and include Icon, Image, Text. Non-visible layout widgets arrange, constrain, and align the visible widgets, and include Center, Column, Grid, Row.

Widgets are immutable in that they don’t change but instead they get replaced or rebuilt when something in the state changes. They are rebuilt based on the updated context.

Flutter widgets can provide data and services to their descendants through special kinds of widgets called InheritedWidget, InheritedNotifier, InheritedModel. They are low level widgets which are used by the provider package. See Section 31.48. for details.

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