Event State Processor

A Flutter package that wrap flutter bloc package for clearer implementation. It's more similar to MVI pattern which:

  • Reflect data state to view (ui)
  • Process ui event to update state then make change in ui

Getting Started

This package is use to develop app which use Bloc pattern clearer, quicker, easier by wrapping complicated bloc usage.

Usage

Using ProcessorProvider instead of BlockProvider for providing

+ event processor instance or  
+ create processor instance for use in child widget.  

Example:

void main() {  
	 runApp( 
		 ProcessorProvider<AuthenticationEventProcessor>( 
			 create: (BuildContext context) => AuthenticationEventProcessor(), 
			 child: const App(), 
		 ), 
	 );
 }

Implement screen widget

  1. Create State extends DataState class. For ex: LoginState

  2. Create Event extends UiEvent class. For ex: LoginEvent

  3. Create Login screen and implement 3 function class LoginScreen extends CoreScreen<LoginEvent, LoginState, LoginEventProcessor> 3.1 handleDataStateChange: handle state change after processor handle event and change widget state. For ex: press login button --> process by processor --> processor change state to LoginFailure because of invalid of login data so we want to show Alert dialog for example, do it in this function.

     if (newState.error != null) {  
       showAlertDialog(context, Text(state.error.message));  
     }
    

    3.2 createEventProcessor: return EventToStateProcessor for use in this widget or its child. For ex just: return LoginEventProcessor(); 3.3 buildScreenUi: for build screen ui base on data state. For ex: if state is state.isLoading is true then show ProgressBar

     if (state.isLoading) LoadingIndicatorWidget() else Container()
    

Dart Versions

  • Dart 2: >= 2.6.0

Contributor

License

MIT

Libraries

eventstateprocessor