I10n theme transalation vs back and forth from 1 language to another

Hello there,

Was having an issue with my dynamic text not being tranlated when going back and forth form one language to another. The problem that I had is that the translation files were loaded prior to Polylang having a chance to update the cookie and setting it the proper language.

After a bit of troubleshooting and trying a few different options, I came up with the below to always set the locale from the url when loading the theme textdomain in function load_theme_textdomain() of I10n.

Add the following filter before load_child_theme_textdomain is being exectuted or load_theme_textdomain if you are creating your own theme.

add_filter('theme_locale', 'CHLD_FixLocale',1,2 );

function CHLD_FixLocale($currentLocale,$theme){
	$uri = rtrim($_SERVER['REQUEST_URI'],'/');
	$urlparts = explode('/', $uri);
	$lastPartOfUrl = $urlparts[count($urlparts)-1];

	$upperLastPart = strtoupper($lastPartOfUrl);
	if($upperLastPart == 'FR' || $upperLastPart == 'EN'){
		$localeLang = substr($currentLocale, 0,2);
		if($upperLastPart == strtoupper($localeLang)){
			return $currentLocale;
		} else {
			return $upperLastPart == 'FR' ? 'fr_FR' : 'en_US';
		}
	}

	$postDb = new PostDb();
	$id = $postDb->GetPostIdByName($lastPartOfUrl);

	if ( $id  != null){
		$db = new TermsDb();
		$serialized = $db->GetObjectLanguage($id);
		$deserialized = unserialize($serialized);
		return $deserialized['locale'];
	}	

	return $currentLocale;
}

Here are the objects being called by the above function:

class TermsDb {
	public function GetObjectLanguage($objectId){
		global $wpdb;
		$query = "SELECT tt.description
					FROM wp_term_taxonomy tt
        	      INNER JOIN wp_term_relationships tr ON tt.term_taxonomy_id = tr.term_taxonomy_id
        				 AND tt.taxonomy = 'language'
				   WHERE tr.object_id = " . $objectId;

		$results = $wpdb->get_results($query);
		return $results[0]->description;
	}
}

class PostDb {
	public function GetPostIdByName($postname){
		global $wpdb;
		$query = "SELECT ID
					FROM wp_posts
        	       WHERE post_name = '" . $postname . "'";

		$results = $wpdb->get_results($query);
		if($results){
			return $results[0]->ID;
		} else {
			return null;
		}
	}
}

Now, I am no WordPress expert and I know that I could have used get_posts() to get to the db as opposed to going straight to the db, but hey, running out of time and since this is in my customized child theme, I took the right to do it that way:)

Anyhow, not sure if this can be made more generic and incorporated into the polylang plugin or if there is a more elegant way of doing this, but this problem costed me quite a few hours of troubleshooting and I felt that it might be worth mentioning:)

You can try it on wformation.com

Thanks!

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