Undefined variable: css_class in include()

Well what a wonder, the variable $css_class doesn't exist :)

Maybe you could check first whether $css_class is !empty().
Alternative we could fix the preprocess function to include a default value = ''.

Well it's only set if the user has defined a css, if the view has not, it's not set.

Here is a patch to set the css_class variable first, and also use drupal_html_class instead of the preg_replace, which I think should be fine?

I like this approach.

+++ b/theme/theme.incundefined
@@ -61,7 +63,7 @@ function template_preprocess_views_view(&$vars) {
+    $vars['css_class'] = drupal_html_class($css_class);

This lowercases the css classes, so it's a bit out of scope as the other parts of views, doesn't do that.

Task for myself: look at previous issues regarding css classes, because there were issues with this function.

Ah, ok, shall we switch it back to the preg_replace that was there before then?

OK, so we should just make sure the variable is set for now?

Yeah keep it simple for now.

Awesome, looks perfect :)

Committed to 6.x-3.x and 7.x-3.x