How do you create and initialize an object asynchronously, but access it synchronously in the rest of the app?
If you use Riverpod, this can be accomplished with a provider override as shown here. 👇
Here's a thread with a complete example. 🧵
In this example, we have a class that takes a Database argument.
But the database can only be created after awaiting for some initialization code.
So we can put all the async init code inside a static method that returns a Future. 👇
Then, we can create a provider for our class.
It may be tempting to use a FutureProvider and just return SembastCartRepository.withDefaultDB().
But that would force us to deal with AsyncValue every time we read the provider.
So we just throw an UnimplementedError instead.
As a result, we can initialize the object we need using await inside the main method.
And we can override the provider with the initialized object when we call runApp().
Then, we can read or watch the provider and get the underlying object when needed.
And this will return the provider that we have overridden in the main method.
This technique works well when initializing dependencies such as repositories or data sources.
In turn, those repositories can have their own methods to fetch data using a Future.
And when fetching data, it makes sense to use FutureProvider (as it can be reloaded/refreshed).
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