课程列表的课程动态数与实际不符

app/views/courses/_course.html.erb

@@ -61,7 +61,7 @@
 
 	<!--gcm-->
 	<p class="stats">
-		<%= content_tag('span',  link_to("#{@course_activity_count[@course.id]}", course_path(@course)), :class => "info") %>
+		<%= content_tag('span',  link_to("#{course_activity_count @course}", course_path(@course)), :class => "info") %>
 		<%= content_tag('span',  l(:label_x_activity, :count => @course_activity_count[@course.id])) %>
 	</p>
 	<!--gcm-->