Plugins usually let the user interact with Freedomotic, e.g. by showing dialog boxes, logging messages and so on. I’d be advisable to let plugin use the user’s language in order to make them much usable and understendable. If you’re a developer and want to add your plugin the capability to ‘speak’ different languages, just follow this simple guide to adapt your code.

Adding internationalization support

Freedomotic ships a mechanism for easily support localized strings and allows the developer to use a prebuild bag of general purpose strings. Moreover the developer could add custom messages on his/her own.

First of all we need to access to API so let’s add the following code

private API api;
private I18n i18n;

api = getApi();
i18n = api.getI18n();

The static function to use in place of your ‘unlocalized’ string is i18n.msg(_STRING_KEY_).

Here a quick example

// old code (non localized)"Hello");
// new code (localized)"greeting"));

In the plugin manifest file you have to add the property <property name="enable-i18n" value="true"/>.

Behind the scenes - what happens when calling i18n.msg()?

Freedomotic reads some system config to automatically guess user locale it searches proper localization string inside /i18n/<Freedomotic locale>.properties.

If the current locale is not defined (translation doesn’t exist) en_UK is used and file is loaded.

Making custom plugin translations

If global translation strings aren’t enough plugin developer could write custom strings and save them using the following path starting from plugin base folder

/i18n/<package-name>.properties\ for en_UK






Accessing custom plugin translations

Just pass the current object as a parameter to i18n.msg()"Plugin " + i18n.msg(this,"plug_name"));

Composing strings

Consider the following example: we want to translate “save environment as”, “save object as”, “save room as” and so on. The translation file looks like this

Key string Default translation it_IT localization
save_as Save as Salva come
environment Environment Ambiente

using a concatenation of strings i18n.msg("save_as") + i18n.msg("environment"); doesn’t work and it’ll result in “save as environment” ...

We can then use basic Java string format like that

Key string Default translation it_IT localization
save_as Save {0} as... Salva {0} come...
environment Environment Ambiente
i18n.msg("save_as",new Object[]{i18n.msg(environment)});

So the second variable is given as replacement for placeholder {0}.

This applies to many placeholders, not only one.