impl. proper fix

src/ItemsPerPageSelector.php

@@ -4,6 +4,7 @@
 
 namespace Atk4\Ui;
 
+use Atk4\Data\Field;
 use Atk4\Ui\Js\JsExpression;
 
 /**
@@ -32,6 +33,11 @@ class ItemsPerPageSelector extends View
     /** @var Callback|null The callback function. */
     public $cb;
 
+    private function formatInteger(int $value): string
+    {
+        return $this->getApp()->uiPersistence->typecastSaveField(new Field(['type' => 'integer']), $value);
+    }
+
     protected function init(): void
     {
         parent::init();
@@ -45,7 +51,7 @@ protected function init(): void
         if (!$this->currentIpp) {
             $this->currentIpp = $this->pageLengthItems[0];
         }
-        $this->set((string) $this->currentIpp);
+        $this->set($this->formatInteger($this->currentIpp));
     }
 
     /**
@@ -60,7 +66,7 @@ public function onPageLengthSelect(\Closure $fx): void
         $this->cb->set(function () use ($fx) {
             $ipp = isset($_GET['ipp']) ? (int) $_GET['ipp'] : null;
             // $this->pageLength->set(preg_replace("/\[ipp\]/", $ipp, $this->label));
-            $this->set((string) $ipp);
+            $this->set($this->formatInteger($ipp));
             $reload = $fx($ipp);
             if ($reload) {
                 $this->getApp()->terminateJson($reload);