Expose API to get current locale

[crizant]

Hi, thanks for creating this awesome plugin.
Is there any ways to get the current locale?

[ilteoood]

Hi, to find system locale I use this function: https://docs.flutter.io/flutter/intl_standalone/findSystemLocale.html

The function that I wrote return a Locale instead of a String. If you prefer, I could make that method public.

[crizant]

Yes please, I see you stored a locale object in FlutterI18n instance, it would be useful if you make it public.

[ilteoood]

That object doesn't represent the system locale, but the locale used by the library for translation purposes.
I will make the _findCurrentLocale public and static.

[crizant]

Yes i would like to get the locale being used by the library. Thanks.

[ilteoood]

Why you need it?

[crizant]

Because my application would change language in runtime, I have an observable store to store the language that the app is using, when it changes, it triggers the component to re-render.
But first I have to know the locale currently using, in order to initialize the observable store.

[ilteoood]

Wait, you don't need to do this.
When the system language change, the library will load the new translation asset and will reload every translation.
Have you a detailed example? Other people do the same thing without this information.

[crizant]

No it's not about the system language.

Like this example from you,
you have to have a state to hold the language, when it updates it triggers rebuild of the layout.
When you take it away, the layout won't rebuild when language changes.

My case is very similar, but in line 32 you initialized currentLang to en, this is incorrect, when the device locale is not english, e.g. Italian.
I need to initialize the state to the locale that your plugin is using.

[Quijx]

@ilteoood
I think @crizant has a point. I also have an application where the language is not dependent on the system language, but on a setting in a settings page.

I did a bit of research and I think that the proper way to control the language inside the app is to set the locale attribute inside the MaterialApp Widget. The value can be dynamic either with something like the scoped_model package or simply a StatefulWidget.

If the locale changes, the load method of the LocalizationsDelegate is called again with the given locale.

If the locale attribute is unset, the locale given to load is dependent on the system language priority list.
Sadly I could not find a lot of documentation on this, but I tested a bit and believe the algorithm for selecting the locale goes like this:

Take the locale with the highest priority in the system language settings, that is also in the supportedLocales attribute in the MaterialApp Widget.
If none is found, use the first locale in the supportedLocales attribute.

This also means that you shouldn't need a fallback file because the fallback locale is managed by flutter.

But since you are not using the locale that is given inside of load in your FlutterI18nDelegate class, switching the language this way does not work. (Also FlutterI18n.refresh is not working for me, but that might have a different reason.)

And when the locale is selected in this way, getting the current locale is really useful because I think the only alternative would be to create a custom Delegate that stores the locale somewhere when load is called.

You should take everything I just wrote with a grain of salt, as I am relatively new to flutter.

[ilteoood]

Hi @Quijx,
your analysis is correct and well formed.
The reason why I don't use the LocalizationsDelegate is to leave the possibility to override the fallback settings of the device (eg: English for everyone, even if the fallback language is Spanish). Also, with this approch, the entire widget tree isn't reloaded when the system language change.
I read your motivation and decided to approve this request. Will be available ASAP.

Thank you,
Matteo

[ilteoood]

Fixed with 9e56c99

Please pay attention to the breaking changes.

Thank you so much for your contribute,
Mattei