MVVM sample project in NuGet Gallery crash with V2

[gmgallo]

I'm implementing the WinUI3 Localizer in my MVVM project duplicating the sample project available with the NuGet package. Unfortunately, SettingsViewModel.cs throws and exception when its constructor reaches the last statement because _localizationService.GetCurrentLanguage() returns an empty string;

    public SettingsViewModel(IThemeSelectorService themeSelectorService, ILocalizationService localizationService)
    {
        _themeSelectorService = themeSelectorService;
        _elementTheme = _themeSelectorService.Theme;
        _versionDescription = GetVersionDescription();

        SwitchThemeCommand = new RelayCommand<ElementTheme>(
            async (param) =>
            {
                if (ElementTheme != param)
                {
                    ElementTheme = param;
                    await _themeSelectorService.SetThemeAsync(param);
                }
            });

        _localizationService = localizationService;
        AvailableLanguages = _localizationService.GetAvailableLanguages()
            .Select(x => new LanguageItem(Language: x, UidKey: $"{"Settings_Language"}_{x}"))
            .ToList();

       // next line throws an exception because  _localizationService.GetCurrentLanguage() returns an empty string "";
        _selectedLanguage = AvailableLanguages.First(x => x.Language == _localizationService.GetCurrentLanguage());
    }

the second problem I encountered is that the It fails to return the default language in a machine where the app runs for a first time (ie no "AppLocalizationLanguage" setting yet). This was solved by preventing that to changing the initalization logic in LocalizationService.cs from this:

    public async Task InitializeAsync()
    {
        await InitializeLocalizer();
        if (await LoadLanguageFromSettingsAsync() is string language)
        {
            await Localizer.SetLanguage(language);
        }
    }

To this:

    public async Task InitializeAsync()
    {
        await InitializeLocalizer();
        if (await LoadLanguageFromSettingsAsync() is string language)
        {
            await Localizer.SetLanguage(language);
        }
        else
        {
            SetLanguageAsync("us-en");
        }
    }

Edit: Whit this change I hopped to be able to get back the localized strings with the default language, but I did not, and _localizationService.GetCurrentLanguage() still returns an empty string.

Maybe I missed to copy a piece of code somewhere?

Implementing the WinUI3Localizer is a great addition to the UX but it is not trivial. Hopefully it gets added to the CommunityToolkit.Mvvm, or, at least a detailed step by step instructions are published with the package for that framework.

[gmgallo]

Also noted that updating the sample project project from MicrosoftWindowsAppSDK version 1.3 to 1.5 crashes at startup.

[AndrewKeepCoding]

Hi, @gmgallo ! I'm going to be away from my laptop, so I won't be able to help you out with this for a couple of days, but can you check the following?

• Does it work by just cloning the sample app? It works on my side.
• Do you have the resources in the "Strings" folder in your project? Also check their properties, "Build Action" and "Copy to Output Directory" match with the sample app ones.

[gmgallo]

Hi @AndrewKeepCoding, Thanks for the quick return!

• Yes, the sample app compiles and works as is. But it uses V1 of the package. And as soon as I upgrade MicrosoftWindowsAppSDK to V1.5 (which I need in my solution), it crashes with an exception very early in the loading process. Downgrading it back to 1.3 doesn't repair the code completely. Unfortuately, that precludes me from using V1.
• Yes, I have two resources,resw files for en-us and es-es. For what I could see stepping through LocalizationService.es initialization the files are loaded, and two language dictionaries are created, but something else is missing or changed from V1 to V2.

I'll revert the changes temporarily until you have some time to look into it.

[AndrewKeepCoding]

I was able to reproduce the issue by just updating to WinAppSDK v1.5. It seems that this is not related to the WinUI3Localizer but to the TemplateStudio project.

The error disappears by bringing a PublishProfiles folder and its contents (*.pubxml files) from another working WinAppSDK v1.5. Recreating a TemplateStudio project from scratch might be a better idea.

[gmgallo]

Hi Andrew, thanks for the return, unfortunately the solution is a risky alternative for me. My project is in the final phase with almost two years of development, countless services and views. Too late to start from scratch a new TemplateStudio and migrate everything over there. I have bad experience trying to recycle parts of old project into a new one. Lots of things go on behind the scenes that can't be fixed just by renaming namespaces.
This is a nice feature for many developers around the world. I hope this makes its way as an add in option to TemplateStudio or the CommunityToolkit MVVM templates.

[AndrewKeepCoding]

Closing this since it seems not to be related to WinUI3Localizer. Reopen this or create a new issue if you need my help.