Added second class to debug 1:n relation, which is working in general

src/admin/common/abstract/model.php

@@ -141,10 +141,14 @@ abstract class AbstractCommonClubsModel
     
     private function loadExternalReferenceAsObject($className, $value)
     {
+        if(is_string($value) && preg_match('/^[0-9]+$/', $value))
+            $value = (int) $value;
+        
         if(! is_int($value))
             throw new Exception('Reference with non-integer value');
         
-        $factory = $this->getFactoryOfClass($className);
+        $factoryName = $this->getFactoryNameOfClass($className);
+        $factory = new $factoryName();
         return $factory->loadById($value);
     }
     
@@ -157,7 +161,7 @@ abstract class AbstractCommonClubsModel
      * @param string $className
      * @return AbstractCommonClubsModelFactory
      */
-    private function getFactoryOfClass($className)
+    private function getFactoryNameOfClass($className)
     {
         if(empty(self::CLASSNAME_MAP[$className]))
         {

src/admin/common/models/factory/club.php

@@ -16,7 +16,7 @@ class CommonClubsModelFactoryClub extends AbstractCommonClubsModelFactory
             'iban'=>array(),
             'bic'=>array(),
             'charitable'=>array('type'=>'int'),
-            'president'=>array('type'=>'int', 'ref'=>'CommonClubsModelUser')
+            'president'=>array('type'=>'ref', 'ref'=>'CommonClubsModelUser')
         );
     }
 

src/admin/common/models/factory/user.php

@@ -0,0 +1,27 @@
+<?php
+
+// No direct access.
+defined('_JEXEC') or die;
+
+class CommonClubsModelFactoryUser extends AbstractCommonClubsModelFactory
+{
+    public function getAttributes()
+    {
+        return array(
+            'user'=>array(),
+            'name'=>array()
+        );
+    }
+
+    public function getTableName()
+    {
+        return '#__club_users';
+    }
+
+    public function getClassName()
+    {
+        return 'CommonClubsModelUser';
+    }
+
+    
+}

src/admin/common/models/user.php

@@ -0,0 +1,19 @@
+<?php
+
+// No direct access.
+defined('_JEXEC') or die;
+
+class CommonClubsModelUser extends AbstractCommonClubsModel
+{
+    protected function getFactory()
+    {
+        return new CommonClubsModelFactoryUser();
+    }
+    
+    public function getName()
+    {
+        return $this->getValues()['name'];
+    }
+
+    
+}

src/admin/views/test/tmpl/default.php

@@ -13,4 +13,4 @@ ClubName: <?php echo $this->club->getMail(); ?> <br />
 ClubName: <?php echo $this->club->getIban(); ?> <br />
 ClubName: <?php echo $this->club->getBic(); ?> <br />
 ClubName: <?php echo $this->club->isCharitable(); ?> <br />
-ClubName: <?php echo $this->club->getPresident(); ?> <br />
+ClubName: <?php echo $this->club->getPresident()->getName(); ?> <br />