Constructing Usecase object may initialize infrastructure resources

[darwingr]

Issues

• ERROR: Tries to load the rootBundle via CSVTableFile.fromAssetBundle(path) before flutter's runApp() is executed. Thus needed flutter plugins & resources are not yet available.
• ERROR: Even a Future could still execute too early
• PERF: Potential opening a file/resource every time a portion of the widget tree is rebuilt?
• PERF: Potential reloading the CSV into List every time a portion of the widget tree is rebuilt?

Under Build # 4

• Main() constructs/initializes repository on the provider
  • Construction of a CSVRepository in turn constructs/initializes the CSVTableFile
  • Construction of CSVTableFile assigns the future computation to load/parse the file
  • Likely acquires the space for it at the same time. Is Future<List<List>> heap bound?
• BingoCardScreen, a stateful widget, initializes/constructs the usecase while taking an existing instance of the repository as a parameter.
• BingoCardBloc takes the existing instance of the repository from the RepoProvider in its constructor when it assigns a usecase

[darwingr]

Solution 1 (used):

Calls WidgetsFlutterBinding.ensureInitialized() in main before repositories are initialized.

Solution 2 (preventative):

Make the _fetchCSVRows property into a getter to a memoized value. The respective factories will store only a function that will be used to memoized when later accessed. Thus deferring the construction and use of the AssetBundle until the calling repository actually has its own methods called.