Comments (15)
Bad idea, at least for now.
A Computed isn't fully destroyed when no-longer used. It'll likely change in the future, but for now you'd have a leak
from riverpod.
If you want a "select", there's one for hooks:
useProvider(myProvider.select((value) => value.foo))
from riverpod.
You could set them as static variables on your Model
Like:
class MyNotifier extends StateNotifier {
static final myComputed =Computed(...)
}
Or keep them all in the same file
from riverpod.
Is there any memory problem if I have many static variables ?
from riverpod.
No. That's the same thing as using global variables.
from riverpod.
Yep. Thanks!
I'll use static variables
from riverpod.
What if it's not global nor static?
For example, is it also fine to use Computed
in every method where the value is necessary, like the way we use select()
of the provider package?
My concern is especially whether the computed is disposed of and stops listening properly at/after the end of each method scope.
class Counter with ChangeNotifier {
int value1;
int value2;
...
}
...
@override
Widget build(BuildContext context) {
final computed = Computed((read) => read(counterProvider).value1);
return Text('value: ${read(computed)});
}
from riverpod.
OK, I'll think about using hooks, hoping it'll be improved in the future.
Thanks anyway!
from riverpod.
from riverpod.
Hi.
I not found select
function on provider
from riverpod.
@rrousselGit
My notifiers extending ChangeNotifier
(not StateNotifier
) have more than one properties, so I use select()
to pick out only part of them for efficiency, preventing unnecessary rebuilds. If the same control is not possible with Computed
, all computed values have to be declared globally or as static properties of some class(es), which will end up in having a long declaration list of Computed...
But it may not be so bad. Probably I'm just having some difficulty, at this early stage, accepting the fact that Computed
and select()
seem similar but are used differently. I'll get used to it soon.
from riverpod.
@tbm98
Have you imported hooks_riverpod
correctly ?
from riverpod.
@kaboc no, but I think select
function only in ChangeNotifier
from riverpod.
But it may not be so bad. Probably I'm just having some difficulty, at this early stage, accepting the fact that Computed and select() seem similar but are used differently. I'll get used to it soon.
Computed is cached and shared
select is local and not cached
from riverpod.
Got it. I'll tell it to myself again and again until I accept it.
from riverpod.
Related Issues (20)
- update the TODO example. HOT 3
- The `API Reference` link in the sidebar leads to `hooks_riverpod` api reference HOT 1
- AsyncValue Issue HOT 3
- Stream ending with BadState when navigating back and forth quickly HOT 8
- Bad state: called ProviderSubscription.read on a subscription that was closed HOT 5
- Generics in Notifier generated HOT 2
- Support ProviderSubscription read inside useEffect dispose.
- Experimentation with macros
- [quality of life] make `riverpod_annotation` re-export utilities such as `@protected` HOT 2
- autoDispose is not working when the widget is disposed,and the same widget is registered again after the previous widget was disposed HOT 8
- `Unhandled Exception: setState() or markNeedsBuild() called during build.` when combining overrides and async providers
- We need a pattern to flow HOT 3
- Add AsyncValue documentation HOT 5
- Add dependency injection doc HOT 2
- Add WidgetRef documentation HOT 2
- await ref.watch(streamProvider.future); resolves on the first yield HOT 3
- What is the recommended way of watching derived values of state exposed through methods ? There's no mention of this in docs HOT 1
- Alternatives to AVOID initializing providers in a widget HOT 1
- Improve error message when Consumer.ref is read after the widget is unmounted HOT 3
- Future provider memory leak HOT 2
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.
from riverpod.