BlocProvider
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BlocProvider is a composable which provides a to its child composable content and all the associated composable tree. The bloc can be retrieved by calls to
It is used as a dependency injection (DI) configuration so that a single instance of a Bloc can be provided to multiple child composables within a subtree. BlocProvider is defined as an extension method of because the lifecycle of the provided Bloc is bound to the the lifecycle of that Screen (similar to ). i.e. when the Screen is disposed so will be all blocs defined with BlocProvider in that screen: the Bloc.close() method will be called and associated coroutine scope Bloc.cscope will be canceled
The create factory method is used to create the Bloc instance (or retrieving it with some Dependency Injection library). The cscope parameter passed to create is a CoroutineScope bound to the current Screen and will be cancelled when the Screen is disposed. It is meant to be passed to the Bloc constructor, that always requires such parameter.
The blocTag parameter is not present in the original flutter_bloc implementation
in the original flutter_bloc implementation there is an option to create the provided bloc lazily.
There is currently no such option in this implementation
same as with an additional blocTag parameter to identify a specific bloc instance in case there is more than one instance of a bloc of the same type to be registered to the current composable subtree.
In flutter_bloc this method was called BlocProvider.value
same as BlocProviderExt but with an additional blockTag parameter
Use this method to obtain a Bloc that was previously configured with BlocProvider in a parent composable.
An optional blocTag parameter can be specified in order to identify a specific Bloc instance in case there is more than one instance of a Bloc of same type registered for the current composable subtree.
The blocTag parameter is not present in the original flutter_bloc implementation
In flutter_bloc the method was called BlocProvider.of. we have renamed it to reflect the usage of remember that is specific to Compose.
In flutter_bloc, when the requestedBloc is not found an exception is thrown. In this implementation instead we return null.
Same as but with explicitly specified bloc instance externallyProvidedBlock that is not a bloc created and bound to the current screen. Lifecycle of this bloc will be managed in the it is associated with, not here.