How to add a new supported language in CQ / WEM

Use case: 

• You want to add new language to CQ
• Change display language options in translator grid
• Change language name and default countries 

Solution:

You can access translator UI in CQ with following URL http://<HOST>:<PORT>/libs/cq/i18n/translator.html

Create new language location for Dictionary

Go to CRXDE lite (or your favorite JCR browser) and add this structure (assuming /apps/myproject/i18n as a typical location for custom apps):

/apps/myproject/i18n [sling:Folder]

    - de [nt:unstructured] [mix:language]

        + jcr:language = de

    - fr [nt:unstructured] [mix:language]

        + jcr:language = fr

Then reload the translator and the path /apps/myproject/i18n should show up in the drop-down at the top.

Note: the translator will only save translations for languages that are actually present underneath the path (e.g. /apps/myapp/i18n), others will be skipped.

Change List of Languages Display in Grid

To change what languages are shown in the translator's grid, create a multi-value string property /etc/languages/languages (node structure must be created), containing the iso language codes (e.g. ["de", "fr", …]). The default is hard coded in the translator and maps the ootb CQ languages: ['de', 'fr', 'it', 'es', 'ja', 'zh-cn']

Add supported language in WCM

• You need to overlay/overwrite /libs/cq/security/widgets/source/widgets/security/Preferences.js to change the list of available languages (used in security admin)
• and overlay /libs/cq/security/content/tools/userProperties (inside change language list under items/common/items/lang/options - similar dialog to Preferences.js) (used for user drop-down in the top right on admin consoles)
• Then you need to add the new language somewhere in the repo, e.g. /apps/yourapp/i18n, following the layout as under /libs/wcm/core/i18n (see also the above section on the translator UI). Stuff under /libs must not be changed!

Here is a sample package:

cq-i18n-add-language-sample.zip

• adds /apps/test/i18n with translation of "New..." in zh-cn ("simplified") and zh-tw ("traditional") languages
• overlays /apps/cq/security/content/tools/userProperties and /apps/cq/security/widgets/source/widgets/security/Preferences.js to add the zh-tw language
• to check, set the current user's language to "Traditional Chinese" and look in the siteadmin: the first button in the toolbar should now be "traditional" instead of "New..."

change language name and default country 

Note: since 5.5 load 21

This means:

• language titles
• country names
• default countries (for codes like "en", "de", etc.)

A language list is stored under /libs/wcm/core/resources/languages. It can be overlayed by copying it to /apps/wcm/core/resources/languages and changing or extending the list there. If you do so, also change the configuration of the language manager com.day.cq.wcm.core.impl.LanguageManagerImpl: set langmgr.list.path = /apps/wcm/core/resources/languages at 

http://localhost:4502/system/console/configMgr/com.day.cq.wcm.core.impl.LanguageManagerImpl.

The default countries, which come into play when resolving the country for a language code such as "en" ("en_GB" would be such a default country), and in turn for displaying flags in the UI, are configured in this list as well. A property defaultCountry on a language node must contain the full code, such as "ja_jp", which would define "jp" as default country for "ja".

Information is provided by Alexander Klimetschek  from Adobe. Many thanks to him.