// add color list on product listing

classes/Product.php

@@ -3045,6 +3045,35 @@ class ProductCore extends ObjectModel
 		return true;
 	}
 
+	public static function getAttributesColorList(Array $products, $have_stock = true)
+	{
+		if (!count($products))
+			return array();
+			
+		if (!$res = Db::getInstance()->executeS('
+					SELECT pa.id_product, a.color, a.id_attribute, pac.id_product_attribute
+					FROM '._DB_PREFIX_.'product_attribute pa
+					'.Shop::addSqlAssociation('product_attribute', 'pa').'
+					JOIN '._DB_PREFIX_.'product_attribute_combination pac ON (pac.id_product_attribute = product_attribute_shop.id_product_attribute)
+					JOIN '._DB_PREFIX_.'attribute a ON (a.id_attribute = pac.id_attribute)
+					JOIN '._DB_PREFIX_.'attribute_group ag ON (ag.id_attribute_group = ag.id_attribute_group)
+					WHERE pa.id_product IN ('.implode(array_map('intval', $products), ',').') AND ag.is_color_group = 1
+					GROUP BY pa.id_product, color
+			'))
+				return false;
+
+		$colors = array();
+		foreach ($res as $row)
+		{
+			if (Tools::isEmpty($row['color']))
+				continue;
+
+			$colors[(int)$row['id_product']][] = array('id_product_attribute' => (int)$row['id_product_attribute'], 'color' => $row['color']);
+		}
+		
+		return $colors;
+	}
+
 	/**
 	 * Get all available attribute groups
 	 *

classes/controller/Controller.php

@@ -356,4 +356,9 @@ abstract class ControllerCore
 		$this->context->cookie->write();
 		$this->context->smarty->display($content);
 	}
+	
+	protected function isCached($template, $cacheId = null, $compileId = null)
+	{
+		return $this->context->smarty->isCached($template, $cacheId, $compileId);
+	}
 }

controllers/front/CategoryController.php

@@ -199,10 +199,38 @@ class CategoryControllerCore extends FrontController
 			// Pagination must be call after "getProducts"
 			$this->pagination($this->nbProducts);
 
+		$products_need_cache = array();
 		foreach ($this->cat_products as &$product)
 		{
 			if ($product['id_product_attribute'] && isset($product['product_attribute_minimal_quantity']))
 				$product['minimal_quantity'] = $product['product_attribute_minimal_quantity'];
+			if (!$this->isCached(_PS_THEME_DIR_.'product-list-colors.tpl', 'productlist_colors|'.$product['id_product']))
+				$products_need_cache[] = (int)$product['id_product'];
+		}
+		unset($product);
+		
+		$colors = array();
+		if (count($products_need_cache))
+			$colors = Product::getAttributesColorList($products_need_cache);
+
+		if (count($colors))
+		{
+			Tools::enableCache();
+
+			foreach ($this->cat_products as &$product)
+				if (isset($colors[$product['id_product']]) && count($colors[$product['id_product']]))
+				{
+					$data = $this->context->smarty->createData();
+					$data->assign(array(
+						'id_product' => $product['id_product'],
+						'colors_list' => $colors[$product['id_product']]
+					));
+					$product['color_list'] =  $this->context->smarty->createTemplate(_PS_THEME_DIR_.'product-list-colors.tpl', $data)->fetch(_PS_THEME_DIR_.'product-list-colors.tpl', 'productlist_colors|'.(int)$product['id_product']);
+				}
+				else
+					$product['color_list'] = '';
+
+			Tools::restoreCacheSettings();
 		}
 
 		$this->context->smarty->assign('nb_products', $this->nbProducts);

themes/default/css/product_list.css

@@ -146,4 +146,22 @@ ul#product_list {
 		background:url(../img/arrow_right_1.png) no-repeat 100% 4px transparent
 	}
 	#product_list li .lnk_view:hover {text-decoration:underline}
-	
+
+	#color_to_pick_list {
+		list-style-type:none;
+		width:125px;
+		float:left;
+	}
+
+	#color_to_pick_list li {
+		float:left;
+		clear:none;
+		padding:0;
+		margin-bottom:1px;
+	}
+
+	#color_to_pick_list li a {
+		display:block;
+		height:20px;
+		width:20px;
+	}

themes/default/product-list.tpl

@@ -43,6 +43,7 @@
 				</a>
 				<h3>{if isset($product.pack_quantity) && $product.pack_quantity}{$product.pack_quantity|intval|cat:' x '}{/if}<a href="{$product.link|escape:'htmlall':'UTF-8'}" title="{$product.name|escape:'htmlall':'UTF-8'}">{$product.name|truncate:35:'...'|escape:'htmlall':'UTF-8'}</a></h3>
 				<p class="product_desc"><a href="{$product.link|escape:'htmlall':'UTF-8'}" title="{$product.description_short|strip_tags:'UTF-8'|truncate:360:'...'}" >{$product.description_short|strip_tags:'UTF-8'|truncate:360:'...'}</a></p>
+				{$product.color_list}
 			</div>
 			<div class="right_block">
 				{if isset($product.on_sale) && $product.on_sale && isset($product.show_price) && $product.show_price && !$PS_CATALOG_MODE}<span class="on_sale">{l s='On sale!'}</span>