Dispatch first bloc event or cubit method, on page start inside StatelessWidget

Question

I have 10 buttons in main menu of my app and each of them contains BlocBuilder inside them.

So when I click on those buttons to open a new page, I want to dispatch the first event, but I don't know how. I can change all classes to stateful widget and then call bloc.dispatch(event) inside initialState() function, but I would like to discover another way, and not sure whether it's the best way

Pls, show your code so we can know where to start from – Confidence Yobo Sep 20 '20 at 16:52 — Confidence Yobo, Sep 20 '20 at 16:52

SardorbekR · Accepted Answer · 2021-11-09T05:24:22.360

9

In order to trigger the first event/method call inside BlocBuilder I had to add bloc argument and give parameter provided my BlocProvider, only after this I managed to call my method.

BlocBuilder<MyCubit, MyState>(
      bloc: BlocProvider.of<MyCubit>(context)..myFunction(),
      builder: (BuildContext context, state) {
//Your code...
}

edited Nov 09 '21 at 05:24

answered Sep 30 '20 at 07:30

SardorbekR

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But first state is missing in blocListener – Islomkhuja Akhrarov Dec 16 '20 at 09:31
For me I had to add the `bloc` argument. – Josef Büttgen Nov 08 '21 at 16:24

score 3 · Answer 2 · edited Oct 02 '20 at 17:27

3

you can use .. operator to add event while declaring like

BlocProvider(
            create: (context) => FirstBloc()..add(InitialiEvent()), // <-- first event, 
            child: BlocBuilder<FirstBloc, FirstState>(
              builder: (BuildContext context, state) {
                ...
              },
            ),

or you can do it inside the initState method as well

edited Oct 02 '20 at 17:27

Christopher Moore

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answered Sep 20 '20 at 16:50

Abhishek Ghaskata

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It can still be achieved without using a statefull widget. as it is adviced to avoid statefull widget as much as possible thus if the need for using a statefull widget is not there, leave it as stateless – Confidence Yobo Sep 20 '20 at 16:54
It didn't work, maybe because my BlocProvider wrapping MaterialApp. In my case BlocProvider is not wrapping BlocBuilder as in your example – SardorbekR Sep 21 '20 at 07:10
you mean like this.? ```BlocProvider( create: (_) => ProfileBloc(ProfileLoading()), // lazy: , child: Consumer( builder: (context, basemodel, _) { return MaterialAppWidget(); }, ), ),``` @SardorbekRkh – Abhishek Ghaskata Sep 21 '20 at 15:22
if yes then you can do like ```BlocProvider.of(context).add(ProfileInitialEvent());```. This also adds the initial event to the bloc where you want to use that bloc. Thanks. – Abhishek Ghaskata Sep 21 '20 at 15:25

Dispatch first bloc event or cubit method, on page start inside StatelessWidget

2 Answers2