Using resx-string from pcl in axml?

Question

I have the resx-files for localization in a portable-class-library in a class MyAppResources. So in code I can get localized strings just with:

 View.FindViewById<Button>(Resource.Id.btnCacheClear).Text = MyAppResources.TextClearCache;

But is there also a way to set this string already in the axml?

 <Button
     android:id="@+id/btnCacheClear"
     android:text= ??   />

Thx, Tom

Answer 1

I would imagine the cleanest way would be to define a custom attribute that would read from your PCL resources via a ResourceManager .

I am working with MvvmCross, and got it working with a custom language binding parser:

public class CustomLanguageBindingParser : MvxBindingParser , IMvxLanguageBindingParser
{
    protected override MvxSerializableBindingDescription ParseBindingDescription()
    {
        this.SkipWhitespace();

        string resourceName = (string)this.ReadValue();

        // Pass the resource name in as the parameter on the StringResourceConverter.
        return new MvxSerializableBindingDescription
        {
            Converter = "StringResource",
            ConverterParameter = resourceName,
            Path = null,
            Mode = MvxBindingMode.OneTime
        };
    }

    public string DefaultConverterName { get; set; }

    public string DefaultTextSourceName { get; set; }
}

And a converter:

public class StringResourceConverter : IMvxValueConverter
{
    private static ResourceManager manager = new ResourceManager(typeof(AppResources));

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        // Ignore value. We are using parameter only.
        return manager.GetString((string)parameter);
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

Register your parser in your MvxAndroidSetup class:

    protected override void InitializeIoC()
    {
        base.InitializeIoC();

        Mvx.RegisterType<IMvxLanguageBindingParser, CustomLanguageBindingParser>();
    }

In your .axml, define a namespace xmlns:local="http://schemas.android.com/apk/res-auto"

And invoke the resource. For example on a TextView: local:MvxLang="Text MyResourceKey"

This hooks into the MvvmCross binding system. The first part "Text" determines the target property, while the second part is parsed as a resource key. The language binding parser translates this into a binding with your custom converter and the key as the converter parameter. The converter does the string lookup based on the converter parameter.