action_mixin 0.1.1+1

Makes it simple to pass events from logic code to UI code use function callback.

action_mixin

Makes it simple to pass events from logic code to UI code.

Why use this package ?

If you used Provider or Riverpod or something similar, how do you display a dialog or show a snackbar from providers?

There are a few ways I usually come across the following:

• Use stream to send events and listen in the UI code
  • Listening to a stream in StatefulWidget is easy in the initState() function. But sometimes you forget to close the stream and the problem occurs.
• Use ProviderListener in Riverpod
  • Even if a provider changes many times in a quick succession, onChange will be called only once, at the end of the frame. You cannot post multiple events at the same time.
• What about Callback? Yes I use it but how to use it?
  • Using the callback seems pretty wordy and I'm a lazy person :P

What is the solution?

Store the FunctionCallback in a Map and initialize it from the UI code. Then you can get it to use according to the predefined key.

Usage

1. Create a ChangeNotifier or StateNotifier or something like that and they use with ActionMixin.
2. Init in the initState() if StatefulWidget or build() if StatelessWidget.

   @override
     Widget build(BuildContext context) {
       // init actions
       useProvider(stProvider).initActions(actions());
      
       return Scaffold(
           appBar: AppBar(
             title: Text(widget.title),
           ),
           body: Column(
             mainAxisAlignment: MainAxisAlignment.center,
             children: <Widget>[],
           ),
           floatingActionButton: FloatingActionButton(
             onPressed: () {
               context.read(stProvider).increA();
             },
             tooltip: 'Increment',
             child: Icon(Icons.add),
           ));
     }
   

3. call it in your logic code

     void increA() async {
       state++;
       callback(LoadingEvent());
       await Future.delayed(Duration(seconds: 1));
       callback(DismisDialogEvent());
       state++;
       callback(ShowSnackbarEvent());
     }
   

Note

If you need to show a snackbar or bottom sheet, use it with StatefulWidget.

See more in the example for better understanding.

Other solution use stream