app\models\EntityModel::getIcon PHP Method

    public static function getIcon($entityType)
    {
        $icons = ['dashboard' => 'tachometer', 'clients' => 'users', 'products' => 'cube', 'invoices' => 'file-pdf-o', 'payments' => 'credit-card', 'recurring_invoices' => 'files-o', 'credits' => 'credit-card', 'quotes' => 'file-text-o', 'tasks' => 'clock-o', 'expenses' => 'file-image-o', 'vendors' => 'building', 'settings' => 'cog', 'self-update' => 'download'];
        return array_get($icons, $entityType);
    }

 public static function renderHtml($accountId)
 {
     $lastClientId = false;
     $clientMap = [];
     $str = '';
     $history = Session::get(RECENTLY_VIEWED, []);
     $history = isset($history[$accountId]) ? $history[$accountId] : [];
     foreach ($history as $item) {
         if ($item->entityType == ENTITY_CLIENT && isset($clientMap[$item->client_id])) {
             continue;
         }
         $clientMap[$item->client_id] = true;
         if ($lastClientId === false || $item->client_id != $lastClientId) {
             $icon = '<i class="fa fa-users" style="width:32px"></i>';
             if ($item->client_id) {
                 $link = url('/clients/' . $item->client_id);
                 $name = $item->client_name;
                 $buttonLink = url('/invoices/create/' . $item->client_id);
                 $button = '<a type="button" class="btn btn-primary btn-sm pull-right" href="' . $buttonLink . '">
                                 <i class="fa fa-plus-circle" style="width:20px" title="' . trans('texts.create_invoice') . '"></i>
                             </a>';
             } else {
                 $link = '#';
                 $name = trans('texts.unassigned');
                 $button = '';
             }
             $str .= sprintf('<li>%s<a href="%s"><div>%s %s</div></a></li>', $button, $link, $icon, $name);
             $lastClientId = $item->client_id;
         }
         if ($item->entityType == ENTITY_CLIENT) {
             continue;
         }
         $icon = '<i class="fa fa-' . EntityModel::getIcon($item->entityType . 's') . '" style="width:24px"></i>';
         $str .= sprintf('<li style="text-align:right; padding-right:18px;"><a href="%s">%s %s</a></li>', $item->url, $item->name, $icon);
     }
     return $str;
 }