BaseBloc class abstract

BaseBloc serves as the foundational class for managing state transitions in a reactive application architecture using the BLoC pattern.

This abstract class extends Bloc from the flutter_bloc package and provides common utilities for handling API responses, managing various error states, and enabling easy navigation during specific scenarios.

Key Features:

• Centralized Handling of API Responses: The handleApiResponse method processes API responses and transitions to appropriate states based on the type of response:

  • Success: Managed using stateFactory or a default state.
  • API Errors: Handled by handleApiError and handleErrorAndException.
  • Network Errors: Managed using handleNetworkException.
  • Parsing Errors: Also processed by handleNetworkException.
  • No Internet Connection: Redirected using handleNoInternetException.
  • Unauthorized Errors: Managed with handleUnAuthorizedException.

• Simplified State Management: Through the BaseFactory, states are dynamically created, reducing repetitive state initialization logic.

• Error Classification: Helper methods such as returnErrorHandler, handleApiError, and handleErrorAndException provide detailed classification and processing for different error types, ensuring consistency across the application.

• Navigation Utility: The _navigate method supports navigation to error-specific screens such as:

  • NoInternetScreen: Displayed during no internet scenarios via handleNoInternetException.
  • MaintenanceScreen: Triggered during server maintenance through handleServerErrorException.

• Lifecycle Management: Implements onDispose and overrides close to ensure resources are properly released when the BLoC is disposed.

Inheritance

• Object
• BlocBase<BaseState>
• Bloc<BaseEvent, BaseState>
• BaseBloc

Constructors

BaseBloc(BaseFactory? stateFactory, {BaseState? initialState})

Constructor for initializing the BaseBloc.

Properties

hashCode → int

The hash code for this object.

no setter, inherited

isClosed → bool

Whether the bloc is closed.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

state → BaseState

The current state.

no setter, inherited

stateFactory → BaseFactory?

Factory for creating specific states dynamically based on the API response.

final

stream → Stream<BaseState>

The current stream of states.

no setter, inherited

Methods

add(BaseEvent event) → void

Notifies the Bloc of a new event which triggers all corresponding EventHandler instances.

inherited

addError(Object error, [StackTrace? stackTrace]) → void

Reports an error which triggers onError with an optional StackTrace.

inherited

close() → Future<void>

Closes the event and state Streams. This method should be called when a Bloc is no longer needed. Once close is called, events that are added will not be processed. In addition, if close is called while events are still being processed, the Bloc will finish processing the pending events.

override

emit(BaseState state) → void

emit is only for internal use and should never be called directly outside of tests. The Emitter instance provided to each EventHandler should be used instead.

inherited

handleApiError<M>(ApiResponse<M>? apiResponse, {BaseState? onApiErrorAction(int?, String?)?, String? errorType}) → dynamic

Handles API errors, such as unauthorized access or server-side validation failures.

handleApiResponse<M>(ApiResponse<M>? apiResponse, {BaseState? onApiErrorAction(int?, String?)?, String? errorType, required Function? retryFunc}) → dynamic

Handles API responses and determines the next state based on the response type.

handleErrorAndException<M>(ApiResponse<M>? apiResponse, {BaseState? onApiErrorAction(int?, String?)?, String? errorType}) → dynamic

Handles API and network-related errors, including unauthorized access.

handleNetworkException(ApiResponse? apiResponse, {String? errorType}) → dynamic

Handles network-related errors, such as connectivity issues or request failures.

handleNoInternetException(ApiResponse? apiResponse, {String? errorType, Function? retryFunc}) → dynamic

Handles no internet connection errors.

handleServerErrorException(ApiResponse? apiResponse, {String? errorType, Function? retryFunc}) → dynamic

Handles server errors, such as maintenance or server-side issues.

handleUnAuthorizedException(ApiResponse? apiResponse, {String? errorType, Function? retryFunc}) → dynamic

Handles unauthorized access errors.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

on<E extends Event>(EventHandler<E, BaseState> handler, {EventTransformer<E>? transformer}) → void

Register event handler for an event of type E. There should only ever be one event handler per event type E.

inherited

onChange(Change<BaseState> change) → void

Called whenever a change occurs with the given change. A change occurs when a new state is emitted. onChange is called before the state of the cubit is updated. onChange is a great spot to add logging/analytics for a specific cubit.

inherited

onDispose() → void

A lifecycle method to clean up resources when the BaseBloc is disposed.

onDone(BaseEvent event, [Object? error, StackTrace? stackTrace]) → void

Called whenever an event handler for a specific Bloc has completed. This may include an error and stackTrace if an uncaught exception occurred within the event handler.

inherited

onError(Object error, StackTrace stackTrace) → void

Called whenever an error occurs and notifies BlocObserver.onError.

inherited

onEvent(BaseEvent event) → void

Called whenever an event is added to the Bloc. A great spot to add logging/analytics at the individual Bloc level.

inherited

onTransition(Transition<BaseEvent, BaseState> transition) → void

Called whenever a transition occurs with the given transition. A transition occurs when a new event is added and a new state is emitted from a corresponding EventHandler.

inherited

returnErrorHandler({String? errorMsg, bool isException = false, String? errorType, ApiResponseType? apiErrorType}) → dynamic

Returns an error state based on the error type and message.

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited