Added data transformers

Form/DataTransformer/ModelsToArrayTransformer.php

@@ -0,0 +1,74 @@
+<?php
+
+namespace Propel\PropelBundle\Form\DataTransformer;
+
+use Symfony\Component\Form\DataTransformerInterface;
+use Propel\PropelBundle\Form\ChoiceList\ModelChoiceList;
+use \PropelCollection;
+
+class ModelsToArrayTransformer implements DataTransformerInterface
+{
+    private $choiceList;
+
+    public function __construct(ModelChoiceList $choiceList)
+    {
+        $this->choiceList = $choiceList;
+    }
+
+    public function transform($collection)
+    {
+        if (null === $collection) {
+            return array();
+        }
+
+        if (!($collection instanceof PropelCollection)) {
+            throw new UnexpectedTypeException($collection, '\PropelCollection');
+        }
+
+        $array = array();
+
+        if (count($this->choiceList->getIdentifier()) > 1) {
+            $availableModels = $this->choiceList->getModels();
+
+            foreach ($collection as $model) {
+                $key = array_search($model, $availableModels);
+                $array[] = $key;
+            }
+        } else {
+            foreach ($collection as $model) {
+                $array[] = current($this->choiceList->getIdentifierValues($model));
+            }
+        }
+
+        return $array;
+    }
+
+    public function reverseTransform($keys)
+    {
+        $collection = new PropelCollection();
+
+        if ('' === $keys || null === $keys) {
+            return $collection;
+        }
+
+        if (!is_array($keys)) {
+            throw new UnexpectedTypeException($keys, 'array');
+        }
+
+        $notFound = array();
+
+        foreach ($keys as $key) {
+            if ($model = $this->choiceList->getModel($key)) {
+                $collection->append($model);
+            } else {
+                $notFound[] = $key;
+            }
+        }
+
+        if (count($notFound) > 0) {
+            throw new TransformationFailedException(sprintf('The models with keys "%s" could not be found', implode('", "', $notFound)));
+        }
+
+        return $collection;
+    }
+}