angular translate instant method does not work

Question

We have a website with angular translate. It works perfectly. We have a variable that we want to fixate with a certain language key. Let's say the site's language has 'en' and 'zh' as options, I want a certain translation to return with 'zh' no matter the language choice.

By browsing the API reference, I found a method called Instant to do just that. However, it doesn't work when we try to call

$translate.instant('zh', 'TRANSLATION_ID')

It returns an error of

TypeError: Object function (a,b,e){var f=d?n[d]:n,i=e?w[e]:u;if(f&&f.hasOwnProperty(a))return i.interpolate(f[a],b);if(h&&!v&&g.get(h)(a,d),d&&c&&d!==c){var j=n[c][a];if(j){var k;return i.setLocale(c),k=i.interpolate(j,b),i.setLocale(d),k}}return l&&(a=[l,a...<omitted>...a} has no method 'instant'

I wonder how to use the isntant method correctly.

Answer 1

It seems like you don't use the method correctly, or probably just misunderstood it.

$translate.instant('ID') expects the translation id as first parameter and interpolation params as second parameter. It then translate the id synchronously instead of asynchronously (which is what $translate() does).

What you want is explicitly translating a translation id in a certain locale no matter what language key is currently used. This is currently not supported yet.

Hope that makes things clear.

Answer 2

Why don't you just embed the word in 'zh'. Don't use $translate there since you obviously don't want to translate that word.

If there's another reason for this; I would suggest:

// store the current language
var currentLanguage = $translate.use();
// change the language
$translate.use("zh").then(function (translation) {
    // then translate here
    $log.debug($translate.instant('SOME_WORD'));
    // set the previous language back when you're fulfilled
    $translate.use(currentLanguage);
});

But since this is async, this may translate some other words to 'zh' in the meantime.

A third way to achieve this would be setting the same translation value for SOME_WORD in each language file.

And a forth way I could think of is translating SOME_WORD only in the 'en' file (no translation value in the 'zh' file) and using 'en' as the fallback language. Such as: $translate.fallbackLanguage('en')