A new Flutter project.
Flutter Form Class Widget
int.tryParse() yields null if value can't be converted to a number
int.parse() throws an error if value can't be converted to a number
lib
├── data
│ ├── categories.dart
│ └── dummy_items.dart
├── main.dart
├── models
│ ├── category.dart
│ └── grocery_item.dart
└── widgets
├── grocery_list.dart
└── new_item.dart