@fzyzcjy Can you file an issue for that? Ideally with some code that reproduces the error you're seeing? I am curious to see how you can do a dependency lookup while a global key move or reparenting is in progress.

@goderbauer Sure I will do that when see the bug again

@goderbauer - is it possible to see which Flutter release this will end up in? I'm getting use_build_context_synchronously lint warnings with Flutter 3.3.5 (channel stable) and the docs refer to BuildContext.mounted but it doesn't appear to be supported yet

I can see this is currently available in the beta branch but not stable as of 3.3.6 Do we have a timeline for this in stable?

BuildContext.mounted does not appear in 3.3.5

BuildContext.mounted does not appear in 3.3.5

@ChangJoo-Park I believe we will need to wait for a least the next minor version (>= 3.4.0)

It's been TWO MONTHS after this was merged and still linter warnings are present, linking to the invalid docs page. Why should this wait for the next minor release, shouldn't this have been the immediate patch (bugfix)? This should be considered bugfix, as linter page is a bug (it provides solution that doesn't build).

@Troyx21 This feature is available in the beta and master channels. Please take a look at the description of our release channels to decide if you want to switch to one of those channels, but we typically only release to the stable channel once a quarter or so (every three months), so it is expected for a change to take about that long to get to the stable channel from the time it is committed to master. If you absolutely need the feature sooner than that, you are welcome to switch to a less stable channel in the meantime.

@gspencergoog I do understand that perfectly well. What I tried to communicate, is that this particular issue, because of the broken linter page and annoing linter warning that affects probably thouthands of codebases, could have been identified as a bug, therefore - this PR could have been labeled as a bugfix - and hence merged into stable as soon as the next bugfix (patch) version was issued (3.3.X).

I'm sorry that it's annoying to you, I truly am. However, we are very unlikely to elevate any annoyance issue to the level of a cherrypick/hotfix into the stable channel because the risk to the stability of the stable channel is too high. We set the bar very high for those hotfixes because we want you to have confidence in the stability of the stable channel, as most developers would rather have annoying linter messages than angry customers. As this page mentions, you are also welcome to patch your local version of Flutter if you must be on the stable channel but need the fix sooner.

Is context.mounted already available in version 3.3.10? I am getting the error The getter 'mounted' isn't defined for the type 'BuildContext'.

I believe we will need to wait for a least the next minor version (>= 3.4.0)

@ValentinVignal Is this confirmed anywhere? I am searching for information about the expected release dates & changes of the versions, but I can't find it… 3 months after the merge "seem enough" to release it into the stable version…

This is my flutter doctor output:
[√] Flutter (Channel stable, 3.3.10, on Microsoft Windows [Version 10.0.22621.819], locale en-150)
[√] Android toolchain - develop for Android devices (Android SDK version 33.0.0)
[√] Chrome - develop for the web
[√] Visual Studio - develop for Windows (Visual Studio Build Tools 2019 16.11.19)
[√] Android Studio (version 2021.3)
[√] VS Code (version 1.74.1)
[√] Connected device (3 available)
[√] HTTP Host Availability
• No issues found!

This is my code:

loadConfigurationFromLocalStorage(BuildContext context) async {
  final localStorage = await SharedPreferences.getInstance();

  if (!context.mounted) {  // <-- Here I get the error 
    print("Context not mounted while trying to load configuration from local storage");
    return;
  }

  final String? storedLanguage = localStorage.getString("lang");
  if (storedLanguage != null) {
    Provider.of<AppProvider>(context, listen: false).setLanguage(storedLanguage);
  }

}

It might be the case that I am using it wrong, but if this is not a proper way of loading data from the local storage and saving it to a provider, how should I do it?

@guplem I don't belong to the flutter team so everything I'm saying is not confirmed. It's only suppositions.

Is context.mounted already available in version 3.3.10? I am getting the error The getter 'mounted' isn't defined for the type 'BuildContext'.

Since context.mounted is a new feature, I doubt they will release it in a patch version (3.3.x), those are reserved for hotfixes. It will be at least a new minor version (>= 3.4.0) (as I said in my comment #111619 (comment)) You can read more about semantic versioning.

3 months after the merge "seem enough" to release it into the stable version…

Flutter releases a new stable version "roughly once a quarter" , so a new stable version should be released soon (but I don't know when). You can read more about the Flutter build release channels.
But there is also no guarantee context.mounted will be included in the next stable release (ex: 3.7.0).

Until then, can something like this work?

extension BuildContextMountedExt on BuildContext {
  bool get mounted {
    try {
      widget;
      return true;
    } catch (e) {
      return false;
    }
  }
}

It looks like it has been released with Flutter 3.7.0 🎉