Start a new Flutter project in Android Studio and choose Flutter Package for the project type. Put your custom widget in the lib folder. Add a folder named example to the project root. In there, add a Flutter app that demonstrates how to use your widget.
Read moreWhat are widgets in Flutter?
Widgets are the central class hierarchy in the Flutter framework . A widget is an immutable description of part of a user interface. Widgets can be inflated into elements, which manage the underlying render tree. Widgets themselves have no mutable state (all their fields must be final).
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