Error: Could not find the correct Provider<TimerState> above this Practice4HomePage Widget Flutter(BLoc)

I got an error when learning bloc in flutter

Error is Error: Could not find the correct Provider above this Practice4HomePage Widget

This happens because you used a BuildContext that does not include the provider of your choice. There are a few common scenarios:

You added a new provider in your main.dart and performed a hot-reload. To fix, perform a hot-restart.
The provider you are trying to read is in a different route.

Providers are "scoped". So if you insert of provider inside a route, then other routes will not be able to access that provider.

You used a BuildContext that is an ancestor of the provider you are trying to read.

Make sure that Practice4HomePage is under your MultiProvider/Provider. This usually happens when you are creating a provider and trying to read it immediately.

For example, instead of:

Widget build(BuildContext context) {
  return Provider<Example>(
    create: (_) => Example(),
    // Will throw a ProviderNotFoundError, because `context` is associated
    // to the widget that is the parent of `Provider<Example>`
   child: Text(context.watch<Example>()),
  ),
}

consider using builder like so:

Widget build(BuildContext context) {
  return Provider<Example>(
    create: (_) => Example(),
    // we use `builder` to obtain a new `BuildContext` that has access to the provider
    builder: (context) {
      // No longer throws
      return Text(context.watch<Example>()),
    }
  ),
}

Solution

You have to provide the bloc to your Practice4HomePage class. One way is to provide the bloc to the entire widget tree i.e. wrapping MaterialApp with BlocProvider or MultiBlocProvider. Another way is to wrap BlocProvider which you are calling Practice4HomePage. So let's suppose you are navigating from the ABC page to Practice4HomePage, you can wrap BlocProvider inside your navigation statement.

Example:

Navigator.of(context).push(
  MaterialPageRoute<HomeForm>(
    builder: (context) => BlocProvider<TimerState>(
      create: (context) => TimerState(),
      child: Practice4HomePage(),
    ),
  ),
),