Recommended flutter resources

I list several useful resources for Flutter dev.

• Official home page: https://docs.flutter.dev/
• Flutter Layout Cheat Sheet: https://medium.com/flutter-community/flutter-layout-cheat-sheet-5363348d037e, snapshot.
• From the same author, Flutter Animation Cheat Sheet: https://medium.com/flutter-community/flutter-animations-cheat-sheet-7f8cebfb850c, snapshot, demo.
• Inherited widget in deep (in Japanese, Flutter大学): https://blog.flutteruniv.com/flutter-inheritedwidget/, snapshot.
• Flutter gallery: a collection of available widgets, promoted by the Flutter team (notice the domain name).
  Web demo: https://gallery.flutter.dev/
  Github source code (with link to the android/linux/window/macOS demos): https://github.com/flutter/gallery
• Flutter recipe: https://docs.flutter.dev/cookbook
• Google Codelabs: https://codelabs.developers.google.com/?product=flutter
• Flutter Patterns Feature Specification: https://github.com/dart-lang/language/blob/976a151a7740042cbefdbe2b378f9227cfb090d0/accepted/3.0/patterns/feature-specification.md

Below are previews of all these resources: