Set language via AJAX (#12785)

* Set language via AJAX

* fix lint

templates/base/footer_content.tmpl

@@ -10,9 +10,9 @@
 			<div class="ui language bottom floating slide up dropdown link item">
 				<i class="world icon"></i>
 				<div class="text">{{.LangName}}</div>
-				<div class="menu">
+				<div class="menu language-menu">
 					{{range .AllLangs}}
-						<a lang="{{.Lang}}" class="item {{if eq $.Lang .Lang}}active selected{{end}}" href="{{if eq $.Lang .Lang}}#{{else}}{{$.Link}}?lang={{.Lang}}{{end}}">{{.Name}}</a>
+						<a lang="{{.Lang}}" data-url="{{AppSubUrl}}/?lang={{.Lang}}" class="item {{if eq $.Lang .Lang}}active selected{{end}}">{{.Name}}</a>
 					{{end}}
 				</div>
 			</div>

web_src/js/index.js

@@ -2314,6 +2314,7 @@ $(document).ready(async () => {
   $('.delete-button').on('click', showDeletePopup);
   $('.add-all-button').on('click', showAddAllPopup);
   $('.link-action').on('click', linkAction);
+  $('.language-menu a[lang]').on('click', linkLanguageAction);
   $('.link-email-action').on('click', linkEmailAction);
 
   $('.delete-branch-button').on('click', showDeletePopup);
@@ -2602,6 +2603,13 @@ function linkAction(e) {
   });
 }
 
+function linkLanguageAction() {
+  const $this = $(this);
+  $.post($this.data('url')).always(() => {
+    window.location.reload();
+  });
+}
+
 function linkEmailAction(e) {
   const $this = $(this);
   $('#form-uid').val($this.data('uid'));