diff --git a/src/IPub/Images/DI/ImagesExtension.php b/src/IPub/Images/DI/ImagesExtension.php
index 3273d01..4e18627 100644
--- a/src/IPub/Images/DI/ImagesExtension.php
+++ b/src/IPub/Images/DI/ImagesExtension.php
@@ -156,7 +156,7 @@ public function beforeCompile()
 		if ($configuration['prependRoutesToRouter']) {
 			$router = $builder->getByType('Nette\Application\IRouter');
 
-			if ($router) {
+			if ($router !== NULL) {
 				if (!$router instanceof DI\ServiceDefinition) {
 					$router = $builder->getDefinition($router);
 				}
diff --git a/src/IPub/Images/Forms/Controls/ImageUploadControl.php b/src/IPub/Images/Forms/Controls/ImageUploadControl.php
index 4920b0b..323ed02 100644
--- a/src/IPub/Images/Forms/Controls/ImageUploadControl.php
+++ b/src/IPub/Images/Forms/Controls/ImageUploadControl.php
@@ -203,11 +203,11 @@ public static function validateImage(ImageUploadControl $control)
 	public static function register($method = 'addImageUpload')
 	{
 		// Check for multiple registration
-		if (static::$registered) {
+		if (self::$registered) {
 			throw new Nette\InvalidStateException('Image upload control already registered.');
 		}
 
-		static::$registered = TRUE;
+		self::$registered = TRUE;
 
 		$class = function_exists('get_called_class') ? get_called_class() : __CLASS__;
 
diff --git a/src/IPub/Images/Storage/FileStorage.php b/src/IPub/Images/Storage/FileStorage.php
index de1f7ae..86dcef9 100644
--- a/src/IPub/Images/Storage/FileStorage.php
+++ b/src/IPub/Images/Storage/FileStorage.php
@@ -62,7 +62,7 @@ abstract class FileStorage extends Nette\Object implements IStorage
 	private $validator;
 
 	/**
-	 * @var Application\IPresenter
+	 * @var Application\UI\Presenter
 	 */
 	private $presenter;
 
@@ -151,7 +151,7 @@ public function getWebDir()
 	 */
 	public function setNamespace($namespace = NULL)
 	{
-		if (!$namespace) {
+		if ($namespace === NULL) {
 			$this->namespace = NULL;
 
 		} else {
@@ -313,7 +313,7 @@ private function generateUniqueFilename($filename, $namespace = NULL)
 	}
 
 	/**
-	 * @return Application\IPresenter
+	 * @return Application\UI\Presenter
 	 */
 	private function getPresenter()
 	{
@@ -325,11 +325,11 @@ private function getPresenter()
 	}
 
 	/**
-	 * @param Application\IPresenter $presenter
+	 * @param Application\UI\Presenter $presenter
 	 *
 	 * @return $this
 	 */
-	public function setPresenter(Application\IPresenter $presenter)
+	public function setPresenter(Application\UI\Presenter $presenter)
 	{
 		$this->presenter = $presenter;