Implement dynamic language switching

packages/auth/src/vpu-auth.js

@@ -54,7 +54,6 @@ class VPUAuth extends LitElement {
 
     connectedCallback() {
         super.connectedCallback();
-        i18n.changeLanguage(this.lang);
         const href = window.location.href;
 
         // load Keycloak if we want to force the login or if we were redirected from the Keycloak login page
@@ -191,6 +190,16 @@ class VPUAuth extends LitElement {
         this.dispatchKeycloakDataUpdateEvent();
     }
 
+    update(changedProperties) {
+        changedProperties.forEach((oldValue, propName) => {
+            if (propName === "lang") {
+                i18n.changeLanguage(this.lang);
+            }
+        });
+
+        super.update(changedProperties);
+    }
+
     render() {
         return html`
             <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bulma/0.7.5/css/bulma.min.css">