I wrote a package for Flutter and added it to the main.dart and it works well but How can I access the value of one of the variables in the package? or how return a variables from it ? For example, in the slider widget, we have access to the value of the slider with on change .
You want to learn how to manage state in flutter.
There are couple of good state management tools:
provider seems to be the easiest one.
Here is a nice tutorial on provider:
https://blog.codemagic.io/flutter-tutorial-app-arhitecture-beginners/
Related
I have a flutter widget ProgressBar, which needs to be notified when a change happens to a value in Flame,
I followed a tutorial which is using overlays.notifyListeners(); to update the StatelessWidget progressBar, but after I updated to the newest Flame version (v1.6.0), this method can not be used anymore, what is the correct way of doing this now?
There are a few different ways to do this, either you can use state management libraries like flame_riverpod or flame_bloc to achieve this, or you can wrap your value in a ChangeNotifier/ValueNotifier and update the state once the value updates.
When changing theme to Darkmode with GetX via Get.changeThemeMode(ThemeMode.dark), most widgets change accordingly. But those widgets using some parameter with Get.theme need a hot reload for the effect to take place.
As a comment suggested here, that is because Get.theme is immutable. Using the extension method context.theme does resolve the issue, however, I do not always have access to a context. Get.context.theme does not resolve the issue. What should I do in this case? Since passing the context to wherever needed kinda defeats the purpose of using GetX.
I am not sure what 'some parameters' you are talking about since you didn't include any code, but you can use the Get.changeTheme() method which takes a ThemeData object and changes the theme accordingly without hot restart.
I have a flutter application which uses a MultiProvider widget at the root of the widgets tree.
The problem is, I need to add a ChangeNotifierProvider to the MultiProvider widget, but later because I can't create it at the beginning (well I could but it makes more sense to do it later *).
How am I supposed to do?
(* for more details about why I would like to create the ChangeNotifierProvider later: The associated ChangeNotifier represents a bluetooth connection that will not be available at the start of the application.)
In these situations I create Provider with object which have some initial values and later I change initial values to actual.
i am new to flutter in one of my project pages set state doesn't work at all no matter what I do I tried every almost everything every time doesn't work so what think can stop set state from working?
note: I am using provider and shared preference
setState(){} only works in StatefulWidget class, I think you are using StatelessWidget. If you want to use it change your class to StatefulWidget.
actually, nothing can stop it from working, and because you are new I am inviting you to accept that there is not something wrong with flutter but with your skill in flutter.
if you provide some code we might be able to help
I'm trying to figure out how to build a custom flutter sdk with a widget that I added.
background: I realized that the PaginatedDataTable requires a header (per this: https://github.com/flutter/flutter/issues/38604) and I'd like to update that widget to make it optional.
Github user wolfcro1984 has a pull request to do the same thing here: https://github.com/flutter/flutter/pull/26352/files
and I'd like to use that code in my current flutter version. However, I'm not sure how to actually build flutter again after that change so that I can use that widget.
How do you build the flutter sdk in order to make a custom flutter version? Is there documentation out there somewhere?
The best way is to copy the code in your own dart file and do the modification. You can go to paginated_data_table.dart, grab all the code and put it in your own .dart file.
How to remove the header :
Go to paginated_data_table.dart (equivalent)
Remove #required before 'header' parameter.
Remove assert(header != null)
Go to Widget build method and remove Semantics. This is under CARD section in comments.
I took a sample from here, did the modification and the result is :
The edits I made are here.
Note : You'll need to change the import part when you copy the standard code in your custom widget.