pigallery2/frontend/app/language/language.component.html

<div class="dropdown" dropdown>
  <button dropdownToggle
          class="btn btn-default dropdown-toggle"
          type="button"
          id="language"
          data-toggle="dropdown"
          aria-haspopup="true"
          aria-expanded="true"
          [ngClass]="isDark?'dark':''">
    <ng-container *ngIf="current != null">
      {{current}}
    </ng-container>
    <span *ngIf="current == null" class="oi oi-globe"></span>

  </button>
  <div *dropdownMenu class="dropdown-menu" aria-labelledby="language">
    <a *ngFor="let lang of languages" class="dropdown-item" href="/{{lang}}">{{lang}}</a>
  </div>
</div>