发布问卷时，该问卷才显示在动态，取消发布后取消显示该动态

app/models/poll.rb

@@ -10,7 +10,7 @@ class Poll < ActiveRecord::Base
   has_many :acts, :class_name => 'Activity', :as => :act, :dependent => :destroy
   # 课程动态
   has_many :course_acts, :class_name => 'CourseActivity',:as =>:course_act ,:dependent => :destroy
-  after_create :act_as_activity, :act_as_course_activity
+  before_save :act_as_activity, :act_as_course_activity
 
   acts_as_event :title => Proc.new {|o| "#{l(:label_course_poll)}: #{o.polls_name}" },
                :description => :polls_description,
@@ -32,7 +32,11 @@ class Poll < ActiveRecord::Base
   #课程动态公共表记录
   def act_as_course_activity
     if self.polls_type == "Course"
-      self.course_acts << CourseActivity.new(:user_id => self.user_id,:course_id => self.polls_group_id)
+      if self.polls_status == 2 #问卷是发布状态
+        self.course_acts << CourseActivity.new(:user_id => self.user_id,:course_id => self.polls_group_id)
+      elsif self.polls_status == 1 #问卷是新建状态
+        self.course_acts.destroy_all
+      end
     end
   end
 end